Environmental Design Principles for the Building Envelope and More _: Passive and Active Measures

Abstract

Given the need to reduce building sector related energy consumption and greenhouse gases (GHG), passive and sustainable buildings are a focal point. Simple methods and techniques, which use appropriate building design, material and systems selection, and reflect consideration of the local environmental elements, such as air and sun, provide thermal and visual comfort with less non-renewable energy sources. These techniques are referred to as environmental or bioclimatic design. There are two types of measures to be taken: passive and active. Passive principles exploit the design and properties of the building envelope to minimise or maximise the heat losses and heat gains respectively, to reduce the energy demand. In addition to passive, active measures such as heating systems and solar power technologies are used to produce and distribute the energy needed to achieve comfort of the occupants.
The present chapter aims at giving an overview of design principles that result in more comfortable and energy efficient buildings. Passive and active design principles are in line with the environmental design concepts. The environmental design principles can be beneficial to the building performance, whether the design ambition is to have a comfortable and functional building with reasonable energy demand or goes as far as achieving sustainable standards such as zero-energy or passive house.

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Delft University of Technology
Environmental Design Principles for the Building Envelope and More _
Passive and Active Measures
Konstantinou, Thaleia; Prieto Hoces, Alejandro
Publication date
2018
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Energy - Resources and Building Performance
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Konstantinou, T., & Prieto Hoces, A. (2018). Environmental Design Principles for the Building Envelope and
More _: Passive and Active Measures. In T. Konstantinou, N. Cukovic, & M. Zbasnik (Eds.), Energy -
Resources and Building Performance (pp. 147-180). (Reviews of Sustainability and Resilience of the Built
Environment for Education, Research and Design). TU Delft Open.
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energy _
resources
and building
performance
Thaleia Konstantinou, Nataša Ćuković Ignjatović and
Martina Zbašnik-Senegačnik [eds.]
TOC

Energy
Resources and Building Performance
Editors
Thaleia Konstantinou, Nataša Ćuković Ignjatović and Martina Zbašnik-Senegačnik
Reviewers
Steve Lo, Dionysia - Denia Kolokotsa
Publisher
TU Delft Open, 2018
ISBN 978-94-6366-034-1
THIS BOOK IS PART OF THE BOOK SERIES
Reviews of Sustainability and Resilience of the Built Environment
for Education, Research and Design
Editors-in-Chief of the book series
Saja Kosanović, Alenka Fikfak, Nevena Novaković and Tillmann Klein
Publication board
Vladan Đokić, Faculty of Architecture, University of Belgrade
Franklin van der Hoeven, Faculty of Architecture and the Built Environment, TUDelft
Nebojša Arsić, Faculty of Technical Sciences, University in Kosovska Mitrovica
Tadej Glažar, Faculty of Architecture, University of Ljubljana
Elvir Zlomušica, Džemal Bijedić University of Mostar
Enrico Anguillari, IUAV Venice
Ana Radivojević, Faculty of Architecture, University of Belgrade
Branka Dimitrijević, University of Strathclyde, Glasgow
Martina Zbašnik Senegačnik, Faculty of Architecture, University of Ljubljana
Linda Hildebrand, Faculty of Architecture, RWTH Aachen University
Thaleia Konstantinou, Faculty of Architecture and the Built Environment, TUDelft
Nataša Ćuković Ignjatović, Faculty of Architecture, University of Belgrade
Tillmann Klein, Faculty of Architecture and the Built Environment, TUDelft
Nevena Novaković, Faculty of Architecture, Civil Engineering and Geodesy, Banjaluka
Alenka Fikfak, Faculty of Architecture, University of Ljubljana
Saja Kosanović, Faculty of Technical Sciences, University in Kosovska Mitrovica
Copyediting
Caitriona McArdle, Architectural Copyeditor, Dublin
Design & layout
Véro Crickx, Sirene Ontwerpers, Rotterdam
Nienke Blaauw, Faculty of Architecture and the Built Environment, TUDelft
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147 KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
Environmental Design Principles for
the Building Envelope and More _
Passive and Active Measures
Thaleia Konstantinou1* and Alejandro Prieto1
* Corresponding Author
  
ABSTRACT Given the need to reduce building sector related energy consumption and greenhouse
gases (GHG), passive and sustainable buildings are a focal point. Simple methods and
techniques, which use appropriate building design, material and systems selection, and
reect consideration of the local environmental elements, such as air and sun, provide
thermal and visual comfort with less non-renewable energy sources. These techniques
are referred to as environmental or bioclimatic design. There are two types of measures
to be taken: passive and active. Passive principles exploit the design and properties of the
building envelope to minimise or maximise the heat losses and heat gains respectively, to
reduce the energy demand. In addition to passive, active measures such as heating systems
and solar power technologies are used to produce and distribute the energy needed to
achieve comfort of the occupants.
The present chapter aims at giving an overview of design principles that result in more
comfortable and energy efcient buildings. Passive and active design principles are in
line with the environmental design concepts. The environmental design principles can
be benecial to the building performance, whether the design ambition is to have a
comfortable and functional building with reasonable energy demand or goes as far as
achieving sustainable standards such as zero-energy or passive house.
 environmental, bioclimatic design, passive, active
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KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
148
1 Introduction
Due to the need to reduce the energy demand and the related GHG, pas-
sive and sustainable buildings that use less non-renewable energy
sources is a focal point. To achieve this, we can apply simple methods and
techniques, starting with an appropriate building design, and material
and systems selection, which make use of environmental elements
such as the air and the sun, to provide thermal and visual comfort to
occupants. These techniques are often referred to as environmental
or 
for shelter. As a term, however,    

thermal comfort and passive, low-energy architecture have been a
starting point for designing new buildings and refurbishment projects.

On the one hand, passive measures are principles that exploit the design
and properties of the building envelope to reduce the energy demand,
by maximising or minimising heat losses and heat gains. On the
other hand, active systems are used to produce and distribute the
energy needed to achieve comfort of the occupants. The use of waste
energy should also be considered on a building or neighbourhood scale.
The present chapter aims at giving an overview of passive and active
design principles that can be applied to the design of the building
envelope and the system selection, resulting in more comfortable and
    

models to assist in the design process. A hierarchical approach to
    
         

and active design principles are in line with the environmental design
concepts and how they are implemented. The chapter concludes with an
explanation of how the application of such measures can be evaluated
based on climate characteristics.
2 A Hierarchical Approach to Sustainable Design
Several authors have discussed the implementation of energy-saving
strategies, organising them according to several parameters. Lechner




climates, then the second tier of passive or hybrid systems should
follow. This second level is based on natural energies and considers
the use of evaporative cooling, earth coupling, or diurnal/nocturnal
ventilation. Lastly, mechanical equipment could be incorporated into
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149 KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
the building in the third tier, if needed, within an already passively opti-
mised building design.
   
sets of strategies to cope with the regulatory functions of the façade.

such as thermal insulation, sun shading or even vegetation; they then

lighting and air conditioning, only if needed. The authors also considered
the use of thermal collectors or PV panels for energy generation, which
relates to the hybrid use of natural energies expressed by Lechner as
an alternative to the use of fossil fuels.
          
        
step scheme, which ranked sustainable measures for the building
          
energy (prevention); then, use renewable energy sources as exten-

        
adopted internationally, starting in 2001 by the former president of
  
         


FIG. 2.1 The “Trias Energetica”
principle
Use fossil energy, if necessary,
as efficiently as possible
12
3
Use sustainable, renewable
energy sources
Reduce energy demand
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Indirect heat gain
Daylight
Other
Organic
Mineral
Oil-derived
Insulated panes
Solar control glazing
Fixed shading devices
Insulated frames
Winter-garden
Double facade
Trombe wall
Boiler
Solar collectors
Renewable fuels
Geothermal
All-air systems
All-water systems
Air and water systems
Direct refrigerant systems
Desiccant
Efficient lights
Efficient appliances
Building Integrated PV (BIPV)
Small scale wind turbines
Heat pumps
Combined Heat and Power (CHP)
Direct
Indirect
Movable/adaptive shading devices
Permanent shading features
(e.g. cantilever)
Attached Sunspace
Comfort ventilation
Nocturnal ventilation
Sorption
Building applied PV panels
Insulation
Insulated windows
Infiltration
Solar control
Direct solar gains
Solar buffer spaces
Ventilation
Evaporative /
adiabatic cooling
Ground cooling
Hydrogeothermal /
deep lake/ocean cooling
Radiative cooling
Heating with efficient
use of non-renewable
Heating from renewables
Electrically driven cooling
Vapour compression cycle
Alternative cooling systems
Heat driven cooling cycle
Electrical appliances
Electricity generation
with RES
Heat protection
Heat gain
from the sun
Heat rejection
Heat generation
Heat dissipation
Electricity
A
ctive /
Equipment
Passive /
Building design
More recently, the New Stepped Strategy (NSS) has substituted the

mising the demand and the use of renewable sources, and it incorpo-
rates a waste stream strategy inspired by the Cradle-to-Cradle principle.
FIG. 2.2 Overview of the passive and
active measures and their objective,
within the scope of environmental
design
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The previous last step, which implied accepting the use of fossil fuels,
becomes obsolete (van den Dobbelsteen, 2008).
Whatever the approach, the common thread is that the measures that
need to be considered during environmental design can, generally,
be characterised as passive or active. Passive measures are related
to the building design and the properties and function of the building
envelope, while active measures include the use of mechanical
equipment. The objective for both passive and active measures is
     
the ultimate goal of achieving thermal  
overview of the measures and their objective. The next sections of this

passive and active measures.
3 Passive/ Building Design Strategies
Passive design principles aim at minimising the energy demand of
the building. Proper consideration of the local climate and environ-
mental elements, building layout, and material properties make
the energy demand reduction possible. Passive principles can be
heat protection, solar heat
gain, and heat rejection.
 Heat Protection

   

versa during summer, when outside temperatures are higher than the
interior temperature. A low thermal transmittance of the components
airtightness and
thermal resistance of the building envelope with the use of insulating
materials for opaque elements of the envelope and insulated windows
for the openings is the main strategy for heat protection.
 
A material with a high thermal resistance that opposes heat transfer
between areas with temperature differences is considered an insulator

building components, can improve the thermal and sound insulation of
the building. They reduce transmission heat losses and produce higher
surface temperatures (Hausladen, Saldanha, & Liedl, 2008).
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INSULATION
MATERIAL
DENSITY ρ
(kg/m3)
THERMAL
CONDUCTIVI-
TY λ (W/(mK))
WATER
VAPOUR
DIFFUSION
RESISTANCE
INDEX μ
FIRE
RESISTANCE
CLASS
EUROCLASS
FORMS
AVAILABLE
APPLICA-
TIONS
INSULATION
THICKNESS
FOR U-VALUE
0.2 W/(m2K)
EMBODIED
ENERGY MJ/
kg

   1-2 E Batts, blown
material,

exterior wall,


18-20 cm 
Hemp   1-2 E Batts, blown
material,

exterior wall,


 
    E Boards, blown
material
exterior wall,


 
Wood-wool
boards
 0.080-0.100  E Boards exterior wall,


 10.8
Cork 100-120  10-18 E Granulate,
board
exterior wall,


 
Reed   2 E Batts exterior wall,


Sheep’s wool   1-2 E Batts, blown
material
exterior wall,


18-20 
Cellulose   1-2 E Loose

material
exterior wall,


18-20 

Rock wool   1-2 A1 Batts, blown
material,
boards
exterior wall,


 
Glass wool   1-2 A1 Batts, blown
material,
boards
exterior wall,


 
Mineral foam    A1 Board exterior wall,

loft, roof

Perlite    A1  exterior wall,

loft

Cellular or
foam glass
10-120   A1 
board
exterior wall,


 
Aerogel 180   A Batts,
granulate,
monolithic
exterior wall,
loft, roof
 

Expanded
polystyrene
(EPS)
  20-100  Board exterior wall,

roof
 108
Extruded
polystyrene

   E Board exterior wall,

roof
 
Polyurethane    C (B for
Metal faced
sandwich
panels )
Board (PUR/

foam
exterior wall,


11-18 101
OTHER
Vacuum
insulation

 
(m K)
  Panels exterior wall,

 
Transparent
insulation
 Board exterior wall
TABLE 3.1 Typical insulation materials

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The insulating effect is the result of the low thermal conductivity of air
that is enclosed in the porous material. There is a bewildering range
of insulating materials, from the familiar polystyrene and mineral wool
to alternative materials that are gradually establishing themselves in

   
    

manufactured, such as vacuum insulation panels. Additional information



Besides thermal and moisture related properties, other parameters

sound insulation and mechanical properties, cost, suitability and ease
of installation, environmental properties and pollutants content, and
production process and chemical composition.


of the various insulation material depends on the application. Loose
materials can be inserted between wooden posts and beams or,
  
matting are cut to size and can then be installed accurately. Rigid
foam insulation boards are appropriate for external applications, due
to higher impact strength.
 
Openings are an integral part of the building envelope, serving view,
daylight and ventilation. These openings are usually operable and made

the shortcomings of glass are its relatively poor thermal properties.
Nevertheless, technology provides the opportunity to use insulated
windows, consisting of panes and frames with lower thermal conductivity.
Over the last decades, multiple panes of glass separated by air spaces
  
improvement of the window insulation value.
Additionally, if the cavity

such as argon or krypton, the conductance of the cavity is even further
reduced, which improves the thermal performance of glazing units.
Moreover, low-emissivity coatings, called Low-E for short, are used
to reduce the surface emissivity of glass. Such coatings consist of a

applied on the faces between the panes, facing the cavity. They are
mainly transparent across the visible wavelengths of light but reduce
the long-wave infrared thermal radiation that is absorbed and emitted
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by the glass pane. This reduces heat loss because the re-emission is
directed to the interior of the building if the coating is on the outside



LowE coating placed in the
interior of the outer pane
LowE coating placed in the
exterior of the innerpane
Cold climate: Solar radiation admitted
Solar radiation
through glazed
surface
Solar radiation
through glazed
surface
Long wavelength heat gener
ated in the room is reflected
back to the interior
-
Part of solar
radiation (long
wavelenght) is
reflected
Hot climate: Part of solar radiation reflected

U-value
is typically used to evaluate
the window pane performance
.
The overall thermal conductivity depends


compares glazing types with different characteristics.

they aim at indicating the thermal performance of the glazing according

GLAZING NUMBER OF PANES GAS INFILL DIMENSIONS (mm) U-VALUE (W/(m2K))
Single glazing 1 n/a  
Double glazing 2 Air  
Double glazing 2 Air  2.8
Triple glazing Air  
Triple glazing Air  
Double glazing with Low E coating 2 Air  
Double glazing with Low E coating 2 Air  
Triple glazing with 2Low E coatings Air  
Triple glazing with 2Low E coatings Air  1.0
Double glazing with Low E coatings and Argon 2 Argon  2.1
Double glazing with Low E coatings and Argon 2 Argon  
Triple glazing with 2Low E coatings and Argon Argon  1.2
Triple glazing with 2Low E coatings 2 and Argon Argon  0.8
TABLE 3.2 Comparison of typical heat transfer through different glazing options

FIG. 3.1 Scheme of coating placement
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As glazing and wall thermal performance improves, the window frame
can create thermal bridging problems. To overcome this issue and reach

  
materials used are ABS (acrylonitrile butadiene styrene), polyethylene
HD, polyamide (nylon), PVC-U (polyvinylchloride), polypropylene,
        
transmittance of the frame section
Uf
considers the thickness of the
frame material, the thermal break material, the glazing, and the sealant.

Most commonly, window frames consist of timber, aluminium, steel,
or plastic. The choice of the frame type depends on the properties and
cost of the material, as well as the desired architectural expression.
MATERIAL SCHEMATIC SECTION * PROPERTIES LIMITATIONS THERMAL CONDUCTIVITY,
λ W/(mK)*
Timber Psychological/aesthetic effect
as a “warm” material
Low embodied energy
Good thermal behaviour
Need regular maintenance
Special considerations against
water penetration, mould and
insect infestation

Timber/
aluminium
Aluminium cladding covering
the entire exterior of the
frame
Weather protection
Psychological/aesthetical
effect as a “warm” material in
the interior
Need regular maintenance
Special considerations against
water penetration, mould and
insect infestation
See thermal conductivity for
timber and aluminium
Aluminium 
Structural integrity
Precise and airtight
construction
Easy maintenance
High thermal conductivity.
Thermal break needed.
High initial cost
High embodied energy

Steel 
metal
High bending and torsion
strength

Thermal break required
High cost
Corrosion protection needed

Plastic (uPVC) 

Low cost
Easy installation and
maintenance
Resistant to water and
corrosion
Prone to heat deformation

Limited structural strength

TABLE 3.3 Window frame types


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 

or other adventitious openings in the building envelope (Sherman &

   
of the leading causes of heating energy loss, as it allows heated air
to escape the conditioned spaces. Even with current standards for
air-tightness, envelope leakage can increase the heating needs by
2
it degrades the effectiveness of the insulation and allows potentially
damaging moisture to penetrate the building envelope. Air leakage
occurs at joints of the building fabric, around doors and windows,
cracks in masonry walls etc., as well as where pipes and cables pass

air-tightness must be coupled with an appropriate ventilation system
to introduce fresh air in a controlled manner, preserving adequate
indoor air quality levels.


       
ventilation is air change per hour (ACH), which refers to how many
      
     
passive

been measured (Stephen, 2010), suggesting that the building stock’s

Careful implementation of strategies throughout the design and
construction phases achieve adequate air-tightness. The materials and
their application depend on the type of leakage. Air-barrier membranes
and sealants, such as expanded foam, gun-applied sealants, tapes, and

With regard to windows, air leakage occurs around the window frame,
at the wall connections, and between the operable parts of the frame.

of the total leakage. This source of air leakage can be tackled by applying
casing tape, poly-return, poly-wrap and foamed-in-place urethane, and

for weather stripping and sealing the edge of the windows are indicated

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 Solar Control
Even though solar radiation is welcome during winter, as will be

overheating of the occupied spaces. The best solar control is proper
external sunshade, intercepting direct solar radiation before it strikes

design, size, and placement, ranging from simple Venetian blinds to
more advanced and complicated systems, which ultimately determine

choice depends on the desired performance, functional and aesthetic

shading, even though it requires higher maintenance.
 
 
system offers the user more options but incurs high maintenance costs,
  
but consider no possibility of control from the user and can exhibit
varying performance during the day. The movable systems are often
referred to as adaptive because they adapt to the changing internal or
external conditions.
Orientation is a major factor in determining the shading type. Horizontal
screening louvres exclude direct sunlight on the south side with little
visual interference. Permanent building elements such as cantilevers
function as seasonal solar screening. They block the high angle sun
rays in the summer, while they enable solar heating during the winter by
allowing lower angle sun rays to penetrate the room. On east and west
façades, movable vertical louvres are preferable because the sun strikes
at low altitudes. By setting the angle of the louvres accordingly, sunlight
can be blocked while retaining some of the view (Hausladen et al., 2008).
FIG. 3.2 Al-Bahr Towers, Abu Dhabi.
The Mashrabiya as seen from the inside
– Sky garden open space
(Photograph
by Abdulmajid Karanouh, Ramboll

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A B
Moreover, avoiding the admittance of excess solar radiation can be achie-
ved with the use of special glazing, such as tinted, coated or switchable
glazing. Glazing can become tinted with small additions of metal oxides

bronze, green, blue or grey but would not affect its basic properties,
except changes in the solar energy transmittance.

which transmission properties can be regulated by a reversible change
of the glass from darker to lighter, or transparent to translucent. Such
technologies include photochromic glass that encompasses coatings of
silver halide, which changes from clear to dark depending on incident
sunlight, while thermochromic glass has a coating of vanadium oxides
which exhibit a reversible semiconductor-to-metallic phase transition
when the temperature rises (Soltani, Chaker, Haddad, & Kruzelecky,
2008). Electrochromic glazing is a technology of switchable glazing
,
which is more controllable, as it is coated with tungsten trioxide that
changes from clear to dark when electrical current is applied. The effect
is that the glazing switches between a clear and a transparent blue-

 

        
popularity is the Liquid Crystal Window. When an electrical current is
applied to the thin layer of liquid crystals placed between the panes,
the crystals are being rearranged and, as a result, the transmission
of the window changes from bright to dark, while maintaining its
      
intermediate states in-between bright and dark. The
g-value
of the
windows

FIG. 3.3 

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A B
FIG. 3.5 Example of Liquid Crystal
Window technology
(photo courtesy of
Merck Window Technologies B.V.)
 
Passive solar heating is essential during winter when energy for
heating is needed for a thermally 
employs transparent elements of the building envelope to collect,
store and distribute solar energy without or with the minimum use of
mechanical equipment (Hyde, 2008). During summer, when the heating
effect is not needed, the glazed parts should be open or protected
with adequate shading.
Passive solar heating primarily occurs in the south part of the building
– or north for the southern hemisphere. On a dwelling level, this is
usually not a big problem, as heat gains can be distributed in short
  
however, it is possible to require zoning in the energy use for different
orientations (Hall, 2008b). Moreover, since the windows are one of
the primary sources of fabric heat losses, the heat gains through the
windows must outweigh the heat losses.
FIG. 3.4 A+B Example of chromogenic
glazing
(photo courtesy of SAGE

Sahlin Photography)
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 Direct Solar Gains
     
     
physical properties of glass allow for using solar radiation to heat
the interior space. The heating effect is based on the principle that
glass is permeable for short-wave radiation (ultraviolet radiation) from
the sun but impermeable for the long-wave heat radiation, which is
emitted by the materials. The orientation, the positioning and size of
the transparent areas, as well as the interior layout for thermal zoning


 Solar Buffer Spaces
Solar buffer space is an intermediate space between the occupied,
interior space and the exterior. This space is unconditioned and heated
exclusively by solar irradiation. As the temperature in the buffer space
is higher than the external temperature, the transmission heat losses

to as winter-gardens, because the temperature in the buffer space can
be within comfort levels for a larger percentage of the year, due to solar

FIG. 3.6 The winter-garden of Pret-a-
loger, TU Delft Campus, NL
Double façade constructions can also create a buffer space. Double
façades include an exterior façade layer, which is separated from the
(interior) façade elements that enclose the occupied space. The distance
between the interior and exterior façade layers can vary. Depending on
the method used to conduct air in the space between the two façades,
double-skin façades can be grouped into four main categories (Knaack,

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–box-window façade, where the air only circulates within one façade
element,
–shaft-box façade, where the air rises in vertical shafts,
–corridor façade, where the air circulates within the gap between the
façades horizontally across one storey, and
– 
stricted gap cavity.
Apart from the thermal buffer effect, a double façade has additional
    
wind protection.
A B
 

with high thermal mass, for example when using transparent outer layer
and a heat-absorbing element between the incident solar radiation
and the space to be heated. Solar energy transmitted through the
transparent layer is absorbed by the outer surface of the wall and

through the air between glazing and wall. Such methods can be of great
  
  
FIG. 3.7 Double façade examples. Post
tower, Bonn (A). Stadttor Düsseldorf,
Düsseldorf (B)
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known technologies of indirect solar heating are the Trombe wall and
the attached sunspaces. Apart from the advantage in 

High thermal capacity
wall absorbs solar
radiation
Solar radiation
through glazed
surface
High thermal capacity wall
radiates heat in the air-gap
High thermal
capacity wall
radiates heat in
the room
Opening to allow
air movement
Air-gap
warms-up
 Heat Rejection
As previously stated, the use of solar control strategies is a highly effective
method of preventing heat from entering the building, minimising the
occurrence of overheating, and thus, reducing overall cooling demands.
However, the presence of internal heat gains and unwanted solar gains,
even using optimised shading systems (due to diffuse solar radiation),
mean that heat prevention strategies alone are not usually enough
to lower indoor temperatures to comfort levels, particularly during
summer season. Hence, it is important to consider passive strategies
aimed at dissipating heat generated or stored indoors to the external

Heat rejection or heat dissipation strategies seek to remove indoor heat,
releasing it into a natural reservoir (air, water, ground). Passive heat
dissipation strategies accomplish this without energy consumption,

such as pumps and fans in so-called hybrid or low-exergy heat rejection
   

heat modulation methods, such as the use of thermal mass for heat
storage, to be dissipated to an external heat sink at a more suitable

construction, such as concrete, terracotta, and limestone, can provide
thermal mass. Nevertheless, for the thermal mass to be
  
    
air temperature and the building thermal mass. Alternatively, Phase
Change Materials (PCM) may be used instead of massive constructive
elements for heat storage purposes.

they employ as base for their cooling principle (Samuel, Nagendra, &
FIG. 3.8 Principle of Trombe wall and
attached sunspaces
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
heat dissipation


mechanical equipment. Therefore, the subsequent description will
focus on the passive cooling principles behind each strategy, without
detailing further use of active components, such as pumps and fans,
for their application in the built environment. Nevertheless, ventilation
strategies will be explored in detail, due to their energy savings potential
and simplicity of implementation under purely passive operation.
FIG. 3.9 Passive/low-ex heat
dissipation strategies according to
the heat sinks used for their cooling
principle
AIR AS HEAT SINK SKY AS HEAT SINK
EARTH AS HEAT SINK WATER AS HEAT SINK
Hydrogeothermal
Deep ocean/lake
Geothermal cooling
Evaporative cooling
Radiative cooling
PASSIVE HEAT DISSIPATION SYSTEMS
Comfort ventilation
Nocturnal ventilation
 Ventilation
Ventilation is the most common heat dissipation strategy, using external
air as a heat reservoir to lower indoor temperatures. Two main strategies
comfort or diurnal ventilation,

demands, improving users’ perceived comfort, while the latter operates
at night time, rejecting stored heat to cool down the building for the
next day. High temperatures during daytime may be counterproductive
for the application of comfort ventilation, but research has shown that
building occupants are willing to accept higher indoor temperatures
if they have access to natural ventilation, promoting its use under
adaptive 

FIG. 3.10 
sided, cross, and stack ventilation
Single-sided ventilationCross ventilation Stack ventilation
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
for buildings and has been consistently researched as a particular topic

Some early experiences dealt with the evaluation of these strategies
via on-site measurements, while others have used simulations to
assess the energy saving potential of their application, discussing
possibilities for implementation in different climate contexts (Artmann,


    
   
       
with high thermal oscillation between day and night (more than
10°C), taking advantage of lower night temperatures to release heat
stored during the day.
A B C

for buildings and has been consistently researched as a particular topic

Some early experiences dealt with the evaluation of these strategies
via on-site measurements, while others have used simulations to
assess the energy saving potential of their application, discussing
possibilities for implementation in different climate contexts (Artmann,


    
   
       
with high thermal oscillation between day and night (more than
10°C), taking advantage of lower night temperatures to release heat
stored during the day.
FIG. 3.11 
façade and air inlets for cross-
ventilation in the GSW building, Berlin
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Natural ventilation (air currents without the use of fans), occurs under
    
driven ventilation. The former relies on wind-induced pressure
differentials and air inlets in the building facade, while the latter results
 
The application of different ventilation principles implies design deci-
sions at the early stages of a building project. Room orientations,
building layouts, and window size and position are factors to consider to
allow for single-sided or cross-ventilation, while architectural elements
such as atriums, solar chimneys, and multi-layered facades have been

 Evaporative / Adiabatic Cooling
Evaporative cooling provides a cooling effect through the evaporation of
water. Thus, internal heat gains are used as latent heat for the phase
change from water to vapour in the humidity content of indoor air.
The effectiveness of the strategy relies on the circulation of air before it
reaches humidity saturation levels, releasing warm and humid air to the
external environment. These techniques have mostly been researched
for hot-arid climate applications, considering them along with ventilation
strategies to bring pre-cooled fresh air into the buildings, such as in

climate contexts in order to explore the potential for implementation
in other regions (Morgado, Melero, Neila, & Acha, 2011).
    
direct and indirect evaporative cooling systems. Direct systems increase
the humidity of the room, directly integrating a water source into space,
or mixing it with an air current, while indirect systems keep the water
in a closed cycle, with the exception of incoming fresh air. The latter is
a more complex system, but its application is suitable for cases where
indoor humidity levels are a relevant issue. Building application has
sparked the exploration of integration possibilities in façade modules or
solar chimneys, in combination with ventilation strategies (Abdallahet

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A B C
 Ground Cooling
Ground or geothermal cooling uses the earth as a heat sink during the
summer season, taking advantage of constant temperatures below
     
requires the use of earth-to-air heat exchangers with improved
effectiveness when coupled with other strategies such as thermal
storage, evaporative cooling, or ventilation by use of solar chimneys.

to geothermal heating by use of renewable sources.
 Hydrogeothermal / Deep Lake/Ocean Cooling
Hydrogeothermal and deep lake/ocean cooling follows the same
principle as ground cooling, but uses a large mass of water as heat

used as a primary source, while the bottom layer of lakes and oceans
    
The applicability of these technologies in the built environment is
limited, being mostly reserved for large infrastructure or offshore
projects. Nonetheless, they are considered in this review for the
sake of completeness.
 Radiative Cooling
Radiative cooling uses the outer space as a heat sink, rejecting heat
in the form of electromagnetic radiation at long waves, from surfaces
FIG. 3.12 
courtyards, Morocco
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
the roof is regarded as the most important passive radiative cooling
element in a building, and design variables such as colour and the use
of movable insulation may increase the effectiveness of this strategy
   
achieve higher performances under clear and unpolluted skies, so
their use is recommended in hot-dry climate zones.
4 Active/ Equipment
Passive design principles alone cannot eliminate energy demand
across all seasons. Even after applying passive measures, the additional
energy required is provided by the technical building systems, which
are the technical equipment for the heating, cooling, ventilation, hot
water, lighting, or for a combination thereof.
 Heat Generation
 
Heating system operation has to cope with heating energy demands
of any given indoor space for the indoor temperature to reach thermal
comfort levels. Hydronics are systems that use hot water for transferring
heat from the heat generator to the heat emitters. The most common
type of heat generator for hydronic systems is a ‘boiler’. Boilers are
available in a broad range of types and sizes and operate with different

energy sources used for heating in various European countries.
FIG. 4.1 Mix of energy sources used for
heating

6% 21% 13% 1% 20% 39%
France
(North & West)
RES biomass electricit
y
coal oil
g
as
20% 1% 29% 41% 3% 7%
Poland
(Central & East)
biomass electricit
y
district heatin
g
coal oil
g
as
27% 18% 32% 23% Spain (South)
biomass electricit
y
oil
g
as





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


Heat pumps can also generate the hot water for hydronic heating
systems. They include a vapour compression refrigeration system
or a refrigerant/sorbent pair to transfer heat from the source using
electrical or thermal energy at a high temperature to the heat sink
 Heat pumps make use of different sources of
low-grade heat. Air source systems (ASHP) offer advantages regarding
space requirements and ease of installation, but they cannot offer
heat

they require a nearby water source. Ground source heat pumps (GSHP)
should not be confused with geothermal energy. GSHP pipes are only
buried 1 meter below the surface to use the solar energy stored in
the ground. Geothermal energy, on the other hand, is heat within the
heat pumps widely
used for heating are reversible air-to-air units that can also be used for

discussing the vapour compression refrigeration cycle.
Hydronic systems can work with different heat emitters, such as ra-

 

Warm air, produced by either stand-alone heaters or a central air-

plant is used for summertime cooling/ventilation. The heat output is
provided mostly by convection through the warm air. Such systems have
a faster response time than hydronic systems.
Combined Heat and Power (CHP) or cogeneration plants provide simul-
taneous generation in one process of thermal energy and electrical
and mechanical energy. The 
cogeneration installations ranges, depending on the technology, from


           
community level (Emmanuel & Baker, 2012).

combined with CHP units. The heat is generated in a central source and
delivered in the form of hot water on demand to a group of buildings (Hall,
2008b). Similarly, the same principle may be used during summer, in the
opposite direction. However, district cooling applications are scarcer.
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169 KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
 Heating from Renewables
Heat can be generated from renewable sources, for example through
active solar systems or biomass. An active solar thermal system
(e.g. from evacuated solar heating panels) combined with large hot
water storage to supply domestic hot water (DHW) and heating, is an

direct solar radiation into other forms of energy, i.e. they preheat water

depend on the system construction. Evacuated solar heating panels
   
perform better in cold, cloudy, and windy conditions. The higher

is needed on the roof.
Moreover, there are heating systems that use renewable fuels, such as

is considered a renewable raw material that provides energy without
producing additional amounts of CO2 within its life cycle, as the amount
of CO2 released has already been absorbed by the plants during growth.
Therefore, it is considered a CO2 neutral source and the primary
energy factor of biomass is lower compared to other fuels (Hegger et
al., 2008). Modern biomass heating systems are an alternative to fossil

systems. There can be various renewable sources used as fuel in
modern heating systems, predominantly wood (in the form of pellets

oil or biogas. The characteristics of the biomass fuel determine how
the system performs.
A B C
Geothermal heating is based on the principle that the temperature in
the ground is constant at a deeper depth, and beyond approximately

Water that is pumped down a borehole into the ground and back to the
surface transfers the heat by simple conduction from the ground to the
water, which is then used to heat the building.
FIG. 4.2 Biomass boiler (A), wood pellet
(B) and wood chips (C)


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KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
170
 Heat Dissipation – Ventilation and Cooling

comfortable temperatures during the summer season, the use of
building services should include complementary mechanical cooling
system. The use of such systems is common in warm climates, and
particularly necessary in commercial buildings, due to high internal heat

have shown that refrigeration and air-conditioning are responsible




basic components to appropriately consider them in terms of building
design, preventing oversizing, and extra energy expenditure.
 
Compression Cycle

room to be conditioned, heat transfer equipment, the refrigeration
machine, heat rejection equipment, and the external heat sink. Cooling
generation is based on thermodynamic cycles. The most frequently used

all installed systems. The working principle is based on the compression
and subsequent expansion of a circulating liquid refrigerant in a closed
cycle. The expanded refrigerant evaporates in contact with indoor air,
absorbing ambient heat. After being compressed, releasing the latent
heat into the environment, the heat later condenses outdoors, to restart

CHILLED WATER
HEAT REJECTION (WATER)
ELECTRIC INPUT
REFRIGERANT
PUMP
EXPANSION VALVE
COMPRESSOR
CONDENSER
EVAPORATOR
VAPOUR COMPRESSION WATER CHILLER
HEAT
REJECTION
SYSTEM
FIG. 4.3 
conventional vapour compression
air-conditioning system
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171 KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
There are several technologies based on vapour compression; these are
categorised into four basic types of air conditioning systems according
   


by ducts, while in all-water systems, water (or another liquid such
as glycol) is chilled and then delivered through pipes. Air and water
 
cooling requirements, usually relying on an all-water system to handle

refrigeration machines and two fans to deliver cool air indoors and

refrigerant systems use air as the transfer medium, but they deliver
cooling directly, without the use of ducts from a centralised refrigeration

well, with the only difference being that they are de-central systems.
Typical systems for building applications derived from each technology

HEAT TRANSFER MEDIUM AIR WATER
Cooling generation Central application - Direct expansion systems
(rooftop units)
- Chilled water systems
(chillers)
Decentral application - Window units
- Split systems
-
Cooling distribution  Hydronic systems /Pumps
Cooling delivery Air cooling - Diffusers 

Surface cooling - - Embedded pipes
(thermally activated building systems)
- Mounted pipes (chilled ceilings)
- Capillary tubes
TABLE 4.1 Common technologies based on vapour compression air-conditioning
 
Driven Cooling Cycles
Alternative systems for space cooling can potentially replace vapour
compression technologies, lowering energy consumption while
eliminating the need for harmful substances used as refrigerants.
Some explored alternatives are sorption, desiccant, magnetic, thermo-
acoustic, thermoelectric, and transcritical CO2 cooling (Brown &

and could be promising alternatives in the future based on further
development; however, this review will focus on two of the most mature
    
sorption and desiccant cooling.
These technologies use heat as the main driver of distinct refrigeration
cycles, only requiring electricity for minor auxiliary equipment such
as pumps and fans. The potential use of heat, a low-grade energy,
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as the main driver for cooling has attracted researchers’ attention
over the years, promoting alternatives based on the re-use of waste
heat, or solar energy through thermal collectors. Nowadays, solar

driven sorption and desiccant technologies with countless research
projects, prototypes, and systems developed for commercial application
in buildings. Similar to vapour compression systems, sorption cooling is
based on the basic refrigeration cycle, which results from the continuous
evaporation and condensation of a particular refrigerant. However, in
sorption cooling, the mechanical compressor unit is replaced by a
‘thermal compressor’ unit that drives the cycle using heat from an
   
a working pair of refrigerant and sorbent. The refrigerant evaporates
    
sorbent and consecutively separated, to end up being condensed again,
rejecting the extracted heat outside.

by the type of sorbent used. Absorption heat pumps use a liquid solution
as sorbent, while adsorption heat pumps use solid sorption materials.
Both technologies commonly use water as the main refrigerant, as well
as a heat transfer medium for cooling distribution on a closed cycle
   
components must be considered next to a parallel ventilation system to
bring fresh air into the building. Absorption chillers represent a mature


   
operation. However, they do not rely on moving parts in their working
  

CHILLED WATER
HEAT SOURCE (HOT WATER)
HEAT REJECTION (WATER)
ELECTRIC INPUT
REFRIGERANT (WATER)
SOLUTION (LiBr)
PUMP
EXPANSION VALVE
HEAT EXCHANGER
GENERATOR
ABSORBER
CONDENSER
EVAPORATOR
THERMALLY DRIVEN ABSORPTION CHILLER
HEAT
REJECTION
SYSTEM
SOLAR
COLLECTOR
HEAT
STORAGE
Desiccant cooling technologies are also sorption-based, using a
working pair of refrigerant and sorbent materials. However, while
sorption cooling works in closed systems, desiccant systems provide
conditioned air directly into the building, under an open-ended process.
FIG. 4.4 
driven absorption chiller
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
air, providing not only temperature control for indoor spaces but also



desiccant-evaporative cooling systems (DEC). At the beginning of the

and then cooled using indirect or direct evaporative coolers. Heat
exchangers are commonly used to pre-cool the incoming air to enhance

   
following this principle, based on different desiccant types. Solid DEC
uses a solid hygroscopic adsorption material, commonly placed on a
rotary bed referred to as a ‘desiccant wheel’; while liquid DEC uses a
hygroscopic solution, which may be applied onto a carrier or directly

FIG. 4.5 
solar driven solid desiccant (DEC)
cooling system
HEAT SOURCE
WATER CIRCUIT
ELECTRIC INPUT
PUMP
FAN
SOLAR
COLLECTOR
HEAT RECOVERY
WHEEL
HEAT
STORAGE
SOLID DESICCANT EVAPORATIVE COOLING (DEC)
HUMIDIFIER
HUMIDIFIER
DESICCANT
WHEEL
INPUT AIR
OUTPUT AIR
FIG. 4.6 Residential electricity





office
equipment ;
7,2%
settop boxes; 1,7%
entertainment;
8,3%
coffee machines ; 1,8%
lighting; 10,0%
heating
systems/electric
boilers; 19,1%
ventilation &
air conditioning; 4,7%
vacuum cleaners;
3,0%
electric oven,
grills & hobs;
6,6%
diswashers; 3,0%
washing & Drying;
7,2%
cold appliances;
14,5%
other;
4,1%
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174
 Electricity
          


energy performance of the building.
 
      
        

EU) provide the regulatory framework. Apart from the products’

determine the energy use, which can be improved by better and
smarter systems control.
 Daylight
Apart from passive heating, the sun can be used for daylight to reduce the
need for electric lighting. Daylight is the preferred form of illumination
in buildings. The human eye has evolved using it, and its full spectrum
output means it delivers better colour rendering properties than any
other light source (Hall, 2008b). Most importantly, with the energy use
     

      
drastically reduce the energy demand.
The amount of sun radiation used for both passive solar heating and
daylight admitted in the space depends primarily on the amount of
transparent and translucent areas of the façade. Additionally, the
       

 Electricity Generation (RES)
    
renewable energy is tapping into natural processes, such as sun
radiation, wind, water movement etc., processes that are perpetually
repeated. Both electricity and heat can be generated by renewable
energy sources. Renewable energy production includes geothermal
and biomass, which were discussed in previous sections, as well as


chapter, we discuss renewable energy production technologies that
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FIG. 4.7 Photovoltaic cells integrated
into the glass panels on the roof of
Akademy Mont-Cenis in Stadtteilpark
Mont-Cenis in Herne, DE
are more commonly used on a building scale, which are photovoltaic

and small-scale wind turbines.
Photovoltaic (PV) assemblies are technical systems that transform
radiation directly into electricity. At the core of the installation, there are
solar cells, combined into modules that produce DC voltage (Schittich,

either formed in a single or multi-crystalline structure. The second

semiconductor materials; while novel developments such as organic
solar cells or polymer cells have been branded as emerging technologies
or ‘third generation’ cells. These refer to technologies which have been
developed past the ‘proof-of-concept’ phase, but further research is
needed to allow for widespread commercial application (Munari-Probst
& Roecker, 2012). Electricity from photovoltaic modules can be fed to
the electricity network, or can cover electricity demand on site.
The annual output of the PV system is also determined by the orientation

          o.

generally speaking, the available building façade area is considerably
larger than the roof space of a building. Thus, incorporating PVs in
façade design results in more electricity production. R&D experiences
have been driven by the evaluation of new concepts such as photovoltaic
double-skin façades and PV integrated shading devices, or the

or colour customisation possibilities for solar modules. The task of
integrating the PVs into the building skin is integral. The visual and
constructional integration must guarantee that the installation does
 
of the building skin.
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176
Wind turbines use the kinetic energy of the air to rotate their blades,
which turns a generator, producing electricity. Wind turbines can
be freestanding on their tower, or can be attached to buildings.
Nevertheless, the latter is still not commonly used, as it can be more
advantageous to place them near rather than on buildings (Hall, 2008b).
Building-integrated turbines, where buildings are designed with wind
energy in mind, are an option for consideration by developers tuned

5 Conclusions
This chapter presented passive and active measures that are in line with
environmental or bioclimatic design principles, aiming at buildings that
provide thermal comfort with minimum or no use of non-renewable
energy sources. Within this framework, the main actions come down to
preventing/minimising the energy demand for heating and cooling and

compete but rather interact with and complement each other. Thus, the
design should consider them in parallel and should not neglect any step.

linked to how the heat is treated by the building envelope and building
systems. Passive measures result in heat protection, heat gain from
the sun and heat rejection, while active measures are related to heat
dissipation and energy generation.
Ultimately, the energy use in the building is related to the users’
wishes and behaviour. The measures described in the present chapter
primarily affect the building-related energy demand, such as heating,
cooling, and ventilation, with the user’s satisfaction naturally being
a precondition. User-related energy demand, such as energy used
     
the building design. However, some of the measures discussed, such
as electricity generation or the design for daylight, can contribute to
reducing this energy consumption.
The        
performance, whether the design ambition is to have a comfortable
and functional building with reasonable energy demand or go as far as
achieving sustainable standards such as zero-energy or passive house.
The choice of measures is ultimately a design choice that will affect
the architectural quality and expression of the building, as well as its
function. The climate and local environmental elements should be
considered, but the decision cannot be based on that alone, as every
design needs to consider many parameters. The objective of providing
the passive and active measure overview is not to give a prescription
but provide knowledge to designers.
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thermal environment in the New Assiut City, Egypt.







Environment,





background_report.pdf





buildings.



by night-time ventilation in Europe.





Renewable and Sustainable
Energy Reviews, 11(2),

Bertoldi, P., Hirl, B., & Labanca, N. (2012).


. Retrieved from





Europe’s buildings under the microscope.



Applied Thermal


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Retrieved
from
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






Emmanuel, R., & Baker, K. (2012).
Carbon Management in the Built Environment
-










framework of triad approaches.


-
ings_using_a_framework_of_triad_approaches




climate-change-and-energy

Assessing the Performances of Typical Envelopes




phenomena.







Passive Low Energy Cooling of Buildings


TOC

KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
178



greenspec.co.uk/
Hall, K. (2008a).

Green Building Press. Retrieved from

Hall, K. (2008b).

Green Building Press. Retrieved from

Hausladen, G., Saldanha, M. d., & Liedl, P. (2008).





-


Applied







Hyde, R. (Ed.) (2008


Earthscan.


Standardization (CEN).


Buildings.

.










Systems



Energy Upgrades.

index.php/faculty-architecture/article/view/konstantiou


. Wiley.

Lyons, A. (2010).
Materials for Architects and Builders.


McMullan, R. (2002).
Environmental science in building.



to climate conditions.
Procedia Engineering, 21


Munari-Probst, M. e., & Roecker, C. e. (2012). Solar energy systems in architecture.


.
Retrieved from


.




-
map_2012_WEB.pdf

future developments.











National University of Singapore (NUS).

economiser strategies on façade selection of commercial buildings.
Energy and Buildings,



air conditioning of building A review.





.





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179 KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More





. Berkeley.





Soltani, M., Chaker, M., Haddad, E., & Kruzelecky, R. (2008). Thermochromic vanadium dioxide

Applied Physics in the 21st Century.

Stephen, R. K. (2010).



van den Dobbelsteen, A. (2008). Towards closed cycles - new strategy steps inspired by the
cradle to cradle approach. in
PLEA Dublin 2008 Towards zero energy building - conference
proceedings
,




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KLABS | energy _ resources and building performance
Environmental Design Principles for the Building Envelope and More
180
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