Variable Façade – Method to apply a dynamic façade solution in Santiago, Chile

Abstract

Sun exposure is a variable phenomenon that forces to conceive building façades as an architectural component that must vary accordingly. On this premise several concepts have been developed that aim to give a dynamic character to the interior-exterior relationship that façades must mediate. In this line, the concept of a Variable Facade is proposed, which corresponds to the application of these ideas in the Chilean context, where the technological and industrial realities do not allow to think of motorization as a unique market solution for variability. Variable Façade is a technical and architectural design concept that ranges from the absence of sun protection to fixed and mobile, mechanized solutions, applied in the control of sun radiation and light transmission with the objective of reaching the best balance between energy performance and environmental comfort for the users of the buildings. The development of this concept is proposed through the combination of 1:5 scale prototype measurement campaigns and simulation processes to bring the experimental results to annual performance analysis. This methodology is proposed as an approach being compatible with the iterations of the architectural design, since it allows to test a greater number of options, avoiding in the prototypes most of the construction variables that the 1: 1 scale forces to solve. We present in this paper the Laboratory of Sun Protections, LAPSO (Spanish acronym for Laboratorio de Protecciones Solares) a measurement platform that will allow the development of the concept of Variable Façade., initial submissions should fulfil the final layout assuming that no revisions shall be necessary

Full text

159 JANUARY 19TH 2017 – MUNICH POWERSKIN CONFERENCE | PROCEEDINGS
Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
Varable Façade –
Methodtoapplya dynamc façade
soluton n Santago, Chle
Claudio Vásquez1, Renato D’Alençon2
1 Escuela de Arqutectura P. Unversdad Católca de Chle, El Comendador 1916, C.P. 7520245 Provdenca, Santago de Chle, tel.
+56.2.2354.5611 clvasque@uc.cl
2 Escuela de Arqutectura P. Unversdad Católca de Chle, El Comendador 1916, C.P. 7520245 Provdenca, Santago de Chle, tel.
+56.2.2354.5613, dalencon@uc.cl
Abstract
Sun exposure is a variable phenomenon that forces to conceive building façades as an architectural
component that must vary accordingly. On this premise several concepts have been developed that aim
to give a dynamic character to the interior-exterior relationship that façades must mediate. In this line,
the concept of a Variable Facade is proposed, which corresponds to the application of these ideas in the
Chilean context, where the technological and industrial realities do not allow to think of motorization as
a unique market solution for variability. Variable Façade is a technical and architectural design concept
that ranges from the absence of sun protection to fixed and mobile, mechanized solutions, applied
in the control of sun radiation and light transmission with the objective of reaching the best balance
between energy performance and environmental comfort for the users of the buildings. The development
of this concept is proposed through the combination of 1:5 scale prototype measurement campaigns
and simulation processes to bring the experimental results to annual performance analysis. This
methodology is proposed as an approach being compatible with the iterations of the architectural design,
since it allows to test a greater number of options, avoiding in the prototypes most of the construction
variables that the 1: 1 scale forces to solve. We present in this paper the Laboratory of Sun Protections,
LAPSO (Spanish acronym for Laboratorio de Protecciones Solares) a measurement platform that will
allow the development of the concept of Variable Façade., initial submissions should fulfil the final layout
assuming that no revisions shall be necessary.
Keywords
façade, adaption, laboratory, scale, testing
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160 JANUARY 19TH 2017 – MUNICH POWERSKIN CONFERENCE | PROCEEDINGS
Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
FIG. 1 Seasonal Comparson of the sun radaton exposure on the facade of an oce buldng n Santago. Drawng by Alejandro
Preto.
1 INTRODUCTION
Exposure to daylght and solar radaton n buldngs s not constant: t vares wth heght, orentaton
and daytme, especally n urban stuatons. To llustrate the problem, Fgure 1 shows the annual
nsolaton of a typcal Santago oce buldng and t s possble to see the varatons between the
derent orentatons and seasons of the year. Therefore, for optmum performance the soluton of
the façades cannot be unform, but should vary accordng to the stuaton t faces.
On the other hand, the use of sun protectons can be transformed nto another problem f appled
wthout consderng ther operatng condtons n relaton to the smultaneous control of sun
radaton and llumnaton, whch do not functon n a correlatve way, e.g. more llumnaton leads
to generates excess radaton and vce versa. To llustrate ths, the sun radaton and daylghtng
transmsson of two prototypes orented to the north n a clear day are presented n the graphs below
(Fg. 2): a fully glazed façade (left) and a glass façade wth fixed horzontal louvers as sun protecton
(rght). Measurements were performed on a 1:5 laboratory probe, where sun radaton on the
(nteror and exteror) glass surface and horzontal llumnance (nsde the façade, deep nsde and
outsde) were measured.
The graph for the unprotected façade (Fg. 2 left) shows the couplng that occurs between the
llumnance and the solar radaton n the area close to the façade reachng ther peak levels at
mdday and declnng durng the mornng and nto the afternoon, followng the sun poston.
Meanwhle, at the back of the room, the daylghtng s neglgble, contrary to what happens close
to the façade, very lkely ndcatng a sgnficant glare. Such couplng of llumnance and radaton
can be consdered a problem snce t nvolves hgh ndoor temperatures, hgh levels of glare and
low llumnance n the background, set of condtons that descrbe problems of vsual and thermal
comfort n the nteror space and an necent use of energy, by the demands assocated wth ar
condtonng and artfical lghtng.
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161 JANUARY 19TH 2017 – MUNICH POWERSKIN CONFERENCE | PROCEEDINGS
Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
FIG. 2 Sun radaton and daylghtng transmsson of two prototypes orented to the north n a clear day wthout (l.) and wth (r)
sun protectons.
2 DECOUPLING OF RADIATION AND LIGHTING
A specfic problem s the couplng of the radaton heat gans and natural lghtng and ts correlaton
wth the solar path n buldngs wth predomnantly glass façades. The cause s that both types
of gans are proportonal to sun radaton passng through the façade. Ths s not compatble
wth the smultaneous requrements of thermal and vsual comfort of users or wth reasonable
energy consumpton. The graph for the façade wthout sun protectons screen (Fg. 2 rght) shows
that when a sun protecton s used, daylghtng and solar radaton are decoupled, ceasng to exst a
drect correlaton wth the energy and lght gans and the sun poston. At the same tme, daylghtng
n the back of the rooms s mantaned n levels absolutely dsparate when compared wth the area
close to the façade, so the problems of vsual dscomfort persst. Ths decouplng and persstence
ndcate that sun radaton heat gans and daylghtng can be dealt wth as separate phenomena, and
suggests an opportunty to thnk about the desgn of sun protectons that work wth both decoupled
but coordnated radaton and daylghtng to optmze the condtons of thermal and vsual comfort,
mnmzng energy demands for ar condtonng and artfical lghtng.
The graphs below (Fg. 3) show the comparson between horzontal lattce protectons, fixed and
moble, both wooden, geometrcally dentcal, orented north and were measured durng the same
summer day n Santago, Chle. The movement pattern n ths case conssts n the louvers turnng
around ther own axs to open or close to sun beams accordng to the ntensty of sun radaton,
whch was regstered by a pyranometer located outsde, parallel to the façade. When fully open,
the louver poston s perfectly horzontal, equvalent to 0°, and when closed perfectly vertcal, 90°.
The electrc servo drve was controlled by an Arduno electronc board that set the blnds to take the
0° poston when the pyranometer reads 0 W/m2 and 90° when t reads 400 W/m2.
The upper graph (Fg. 3 left) represents n red the sun transmsson of a fixed louver protecton and
the blue represents a moble protecton, movng accordng to the descrbed pattern. It s sgnficant
that around noon, when the horzontal louvers work ecently, sun radaton transmtted by the
moble louvers s almost half of that transmtted by fixed louvers, whch should result n a sgnficant
decrease n energy consumpton for coolng n summer.
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162 JANUARY 19TH 2017 – MUNICH POWERSKIN CONFERENCE | PROCEEDINGS
Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
FIG. 3 Left: Sun radaton transmsson (W/m2) n a day cycle for a wooden horzontal lattce, fixed (red) and moble (blue); Rght:
llumnance (lux) n a day cycle for a wooden horzontal lattce, fixed (red) and moble (blue)
The second graph (Fg. 3 center) shows what happens to the llumnance on the perphery of
the rooms, close to the façade durng the day. It s notceable that the stuaton of both louvered
protectons s very smlar: from 10 a.m. llumnances range between 500 and 1200 lux, acceptable
for oce actvtes. It s mportant to keep n mnd that ths movement pattern was actvated
only by sun radaton, .e. t does not respond to the avalablty of natural lght, so t would be
possble to stll mprove the lghtng performance of the moble louvers by actvatng a lghtng
(llumnance) optmzed pattern.
The thrd graph (Fg. 3 rght) shows the eect of the lghtng movement pattern n the back of the
room, some 6 to 8 m away from the façade. Illumnance s compared n terms of lght transmsson
factor, a crtcal ndcator n ths area of a plan. In red, the fixed lattce shows that the llumnance
never reached 150 lux, and lght transmsson ratos dd not exceed 3%. However, the moble lattce
reached values between 50 and 250 lux wth ratos reachng almost 5%. Although the result s not
optmal, ths analyss shows that the movement acheves better results n lghtng the back of a
room, although n ths case the movement pattern was sun radaton, as we have explaned.
3 STATE-OF-THE-ART
A recent general definton that meets the above s the one proposed by Loonen et al n hs artcle
“Clmate adaptve buldng shells: State-of-the-art and future challenges” (Loonen et al, 2013),
focused on the applcaton of what the authors call Clmate Adaptve Buldngs Shells, CABS, to
acheve the hghest levels of performance. Compared to conventonal facades, CABS oer potental
opportuntes for energy savngs, better ndoor envronmental qualty, combnng actve and passve
technologes n the buldng envelope. Accordng to the concluson of Loonen et al, these concepts
cannot yet be consdered mature and future research areas are dentfied and n partcular the new
challenges facng the researchers n ths specfic field.
Dverse concepts have been assocated wth such solutons, known as Actve Façades (XU et al., 2008)
or Adaptve and Responsve Façades, ARF (Wggnton, 2002; Knaack, 2007) defined as those whch
have the ablty to adapt or respond to envronmental condtons or use. The common vson of these
systems, also generally known as Intellgent Façades (Compagno, 2002), s the concepton and desgn
of the façade system as an actve entty lnkng wth the outsde, under the logc that f the external
condtons to whch a façade system faces vary, the buldng should vary lkewse.
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163 JANUARY 19TH 2017 – MUNICH POWERSKIN CONFERENCE | PROCEEDINGS
Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
Recent research has shown that the automaton of facades leads to mprovement n the nteror
lghtng condtons (Mettamant et al, 2014) partcularly by algorthms or control patterns n
greenhouses (Basten and Athents, 2011) and n façade systems appled to buldngs (Aste et al,
2012). These studes have shown that sun protectons movement optmzes the qualty of the ndoor
envronment and assocated energy consumpton. Ths s especally mportant n buldngs n the
tertary sector where nternal loads are hgh and constant durng daylght hours.
Although t has already been stated that the varablty of the façade system s a sutable soluton
to respond to sun trajectory, the coordnaton of parallel movements that smultaneously respond
to llumnaton and sun radaton s an unexplored field that has no solutons at the technologcal
level. Favono et al (2014), and others n the field of desgn and development, have proposed a
new approach to the development of new technologes, by means of a method to define the deal /
optmum range of adaptve thermo-optcal performance of a glass façade wth derent reacton
tmes, n order to evaluate the potental of future adaptve glass façades. Among the exstng studes,
some focus on bult-n solutons and prototypes, such as ACTRESS (ACTve, RESponsve and Solar
Façade), or user nteracton n control systems (Favono et al, 2016). Goa and Cascone (2014), on the
other hand, present the results of an nvestgaton to evaluate the advantages of an deal adaptve
buldng skn based on the systems of constructon of conventonal claddngs.
These nvestgatons show the expected advantages, but do not address specfic solutons or
strateges for ths problem, whch s what we propose to develop n ths work. All of these studes, one
way or the other, concde n the mportance of coordnatng n the archtectural desgn the multple
possbltes of these technologes n order to make them eectve or even possble. Ths poses a
specfic challenge for archtects as t nvolves the role of the dscplne as a coordnatng actor n the
desgn process. From ths pont of vew, a decsve varable s the vablty that prncples elaborated
at a scentfic level have n a specfic market and ther relaton wth the technologcal realty of
the buldng ndustry.
4 THE CHILEAN CONTEXT
The fundamental objectve of ths work s to address ths perspectve, whch nvolves approachng
the scentfic problem and ts specfic feasblty n the context of a less developed, but steadly
growng country lke Chle. Another reason to nvestgate ths partcular case s the clmate of
Santago, the captal of the country, located n a regon wth a prevalng cool sem-ard clmate (BSk
accordng to the Köppen clmate classficaton), wth Medterranean (Csb) patterns.Our prevous
studes have focused on establshng for the Chlean case the correlaton between the transparent
area of the façade and the energy consumpton of buldngs and on establshng levels of thermal
comfort of people workng n them (Vásquez et al, 2015). Regardng lghtng comfort, we have
establshed as man problems glare n areas near the façades and low lghtng n the back of the
rooms. These lead users to block the lght from the outsde, and to use artfical lghtng durng the
day. At the same tme, we have establshed that the correlaton between the transparent surface
and the energy consumpton of these buldngs reaches R2 value of 0.97 n summer. We know that
n summer curtan walls oce buldngs completely fal to meet the thermal comfort of users for
55-60% of the workng day and come to reasonable avalablty of natural lght n a 22-25% of the
year. These results rse the nvestments n energy for lghtng and ar condtonng, and drectly
aect labor productvty.
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164 JANUARY 19TH 2017 – MUNICH POWERSKIN CONFERENCE | PROCEEDINGS
Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
On the other hand, we have also been able to establsh the avalablty of more than 745,000 m2 of
façades that could use sun protectons to mprove performance n over 2,000,000 m2 of oce area,
consderng buldngs wth permsson or final approval n the 2005-2013 perod only. The use of
some sunscreen reaches only 27% of bult stock of oce buldngs, but ther applcaton does not
lead to the best performance of the buldngs that have them, ndcatng that that sun protectons are
rarely used and when appled they are not correctly used. Both buldngs now n operaton and those
that are stll beng desgned and bult wth the same crtera, represent an opportunty to mprove
both comfort and energy performance through varaton of sun protectons dependng on solar
radaton and daylghtng as ndependent phenomena juxtaposed n one system soluton.
The need to scentfically address the problem s assocated wth the need to establsh expermentally
the potental and lmtatons that the decouplng of radaton and lghtng performances have.
The nternatonal state of the art on the subject suggests that moble sun protectons are the best
soluton to solve the problem we face, however ths must be proven by experment before beng
technologcally developed n Chle.
4.1 VARIABLE FAÇADES IN CHILE
In Chle, the possblty of usng dynamc sun protectons s avalable n the market by means of
several products oered by the company Hunter Douglas. These solutons for façade adaptablty that
have been appled n a few buldngs currently n operaton. However, the emphass of these products
s on respondng to an automated movement patterns, not to the condtonng of an nner space wth
specfic envronmental qualtes. The development of ths concept, assocated wth multple patterns
determned by more than one type of external stmulus, such as radaton and natural lght, for
example, has not yet been developed or mplemented. In Chle, there are two buldngs that apply a
varable poston system, consstng of outdoor roller blnds, they are:
FIG. 4 Transoceánca Buldng, + Archtects. Santago de Chle (2010). Photograph: + arqutectos
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Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
Transoceánca Buldng, + Archtects (Fg. 4): ncludes s a soluton that combnes statc and dynamc
solutons juxtaposed to the way ths project proposes, that s: a roll-up curtan system that s drven
by drect solar radaton, detected by a mn meteorologcal staton located on the roof of the buldng.
The fixed sun protecton s a wooden grd that complements the work of the curtan. The system was
nstalled and s mantaned by an external company that s responsble for ts operaton.
ITAU buldng, desgned by Estudo Leyton Archtects, (Fg. 5) s the first LEED-certfied corporate
buldng bult n Chle and has an automated external curtan that s part of a centralzed
system of envronmental management of the buldng. The curtans are also actvated by the
presence of sun radaton.
These cases are mportant nnovatons n Chle and show that there s a need to develop solutons
that consder the use of moble systems drven by clmatc factors. However, n these cases
movement patterns focus exclusvely on blockng radaton n bnary form; they only have two
postons: open or closed, wthout ntermedate adjustments. Moreover, n both the lghtng depends
on the weft of the fabrc of the curtans, and the lghtng n the back of the room plan s not resolved,
and the llumnance or the contrast on the front (close to the façade) s also not assured. In the
Chlean market for sun protecton systems, the exstng avalable solutons are exteror roller shades,
of the knd appled n the prevous cases, awnngs and varous moble louvered blnds solutons.
Automaton s an added value that depends on the project and ts applcaton s not assocated
wth an optmzed or juxtaposed movement pattern. These solutons could be further mproved by
consderng sun radaton and lghtng as problems that must be addressed ndependently and
coordnated for optmal system performance of the façade.
FIG. 5 ITAU Bank Buldng, Estudo Leyton, Archtects. Santago de Chle (2009). Photograph: Google Streetvew
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In ths technologcal and commercal context, the contrbuton of ths project wll be the ntroducton
of juxtaposed movement patterns able to coordnate sun lghtng and solar (radaton) gans n
buldngs, an unexplored field n whch there are no technologcal solutons n Chle or abroad
meetng Chlean constructon standards and market condtons. The soluton to ths problem
should then focus on smple nnovatve, usng smple movement patterns typcal of the solutons
now appled n Chle, yet juxtaposton patterns wll add attrbutes that should make the soluton
be consdered as a varable form soluton. The use of smple movement patterns wll ensure that
major components and system parts, such as motors and mechancal parts, are packable and readly
avalable n the market followng an analyss of specfic requrements. At the level of technologcal
development are two fundamental challenges: the measurement, processng and transmsson of the
nformaton to the actuators, whch wll requre an especally developed computer system; and the
desgn of movement patterns, on whch the current scentfic research s focused.
5 VARIABLE FAÇADE
Evdence both n the avalable lterature and our own expermental experence (figs. 2 and 3) shows
that moble sun protectons are capable of mprovng the energy performance relatve to statc
systems. The possble optons for change nclude: no protecton, the use of fixed shadngs and the
use of a mechancally adjusted sun protecton system based on patterns assocated wth varatons
n sun radaton and sun lght. The latter s the center of nnovaton of ths project. Internatonally,
exstng moble facades solutons can be dvded nto two groups:
– Varable Form Systems: consst of solutons where sun protectons are deformed and then return
to the orgnal shape, ether by the acton of a mechancal foldng mechansm, by deformaton of a
flexble materal or by the use of pneumatc structures. They characterstcally need to solve complex
mechancs, wth an emphass on a form respondng to the deformaton tself, and not to an external
pattern. They are complex n ther desgn and dcult to apply as standardzed solutons.
– Varable Poston Systems: consst of solutons where sun protecton s not deformed but s shfted
mantanng ts form. Accordng to the movement, they can be of stepper movement, rotate around
an axs, or overlap layers. Such solutons are characterzed by the smplcty and regularty of ts
mechancal systems and are found more often n archtecture solutons.
Ths dscusson, as well as the lterature revew show that adjustment through moton mproves
the performance of a sun protecton. However, t s stll unclear under what condtons ther use s
feasble n relaton to a statc soluton. Thus, t s necessary to undertake a process of expermental
research to answer the followng questons:
– Under what condtons does the movement of a sun protecton acqure comparatve advantages over
the same statc soluton?
– What movement patterns are sutable for ndependently optmzng day lghtng and radaton gans
performance of a moble lattce?
– What relatonshp can be establshed between the daylghtng pattern and the radaton gans pattern
and what lmtatons on the performance of each would the juxtaposton of both mpose?
– What materals are sutable for sunlght protecton and radaton gans protecton for the clmate and
envronmental context of the cty of Santago?
Answerng these questons wll allow us to develop the concept of Varable Façade, whch means the
adaptaton of findngs made at the scentfic level to the realty of a façade technology n a specfic
market segment wth lttle development.
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Varable Façade – Methodtoapplya dynamc façade soluton n Santago, Chle
6 SUN SHADING LAB – LAPSO (LABORATORIO
DE PROTECCIONES SOLARES)
In order to address these questons, a method has been organzed based on computer models and
scaled prototypes. Computer models are used to define solutons by definng relevant parameters,
teratng the models and selectng the optmum solutons by means of a multple-varable selecton
method. Scaled prototypes are used to test under real condtons the solutons prevously selected;
these allow for an easer constructon of the samples (as opposed to full-scaled mockups) and do
not compromse the results of llumnance and sun radaton measurements; however, they do not
delver relevant results n temperature or energy consumpton, and are thus lmted to calbraton of
computer models n specfic, relevant results.
The process s dvded nto three stages: (1) Definton and constructon of sun protecton prototypes,
whch conssts of searchng for optmzed solutons for the three types of solar protecton (screen,
horzontal louvers and vertcal louvers), types of performance (radaton and llumnance) and
varaton (fixed and moble); (2) Expermental measurements, whch conssts of measurng the
performance of sun protectons n the laboratory; (3) Extrapolaton of results, whch conssts of the
calbraton of a model that allows extrapolatng the expermental results to ther energy performance.
Ths artcle reports the first stage, whch s hghlghted n a box, as t represents the sustaned
progress at the current stage, and t s shown n the chart (fig. 6).
FIG. 6 Work method dvded nto three stages: (1) Definton and constructon of sun protecton prototypes; (2) Expermental
measurements; and (3) Extrapolaton of results
Phase (1) conssts of the definton and constructon of prototype and the obtaned results are
derentated from the type of sun protecton and are descrbed n the followng table (Table 1).
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TABLE 1 Definton of prototypes derentatng the type of sun protecton
In order to test the concept of Varable Façade, four test chambers were bult n a scale of 1:
5 to collect the sun radaton and lght performance data of three parallel façade system prototypes
plus a control chamber, whch make up the man component of the research laboratory. Because of
the scale, these cameras have the restrcton of not representng the phenomena of heat transfer,
however they do have the ablty to represent the solar and lght gans that ths project requres.
The boxes are bult wth 50mm thck walls made of metal faces and hgh densty polyurethane nfill,
and are shown n the drawngs below (Fg. 8).
FIG. 7 Dagram showng the parts of the test chambers (top left) and layout of four chamber, three for testng sun protectons plus
one control chamber on the test platform (top rght) and mage of the bult chambers (bottom)
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The chambers are opaque n five faces and the sxth s a wndow that occupes the entre front,
representng a fully glazed façade system. Parallel to the transparent face, a substructure s placed
that allows to nstall prototypes of exteror sun protectons. The upper cover of the chambers can
be opened to allow access to the man space where the nternal measurements are made and to
nstall the sensors that wll make the readngs of the parameters to be regstered. Each chamber
also has a compartment n ts back to nstall the electronc system collectng and sendng data.
In addton, the chambers are equpped wth ar extractors to control temperature excess that mght
aect the nstruments n the nteror and are wheeled to facltate ther transport and exact locaton.
The measurements conducted n the chambers are the followng:
– Sun radaton: the pyranometers are located both drectly on the nteror face of the façade to
measure the transmtted solar energy, and on the outsde, to measure the solar gan ndex. For ths
calculaton surface thermometers are also used that allow to evaluate the energy re-rradated by the
glass. Measurements are made every mnute so that a detaled radaton curve s obtaned.
– Illumnance: three luxometers are arranged n lne to evaluate the lght gradent generated by
the sun protecton. In addton, a luxometer s placed on the outsde to calculate the rate of lght
transmsson, both at the front and at the back of the box. Also, at the rear of the box a camera slot s
avalable that allows to make HDR mages that are then taken to a false color analyss to evaluate the
lumnance levels of the sun protecton. Measurements are also performed mnute by mnute.
The results obtaned are used to generate a database that allows the constructon of the
energy extrapolaton model and the qualty of the nteror envronment, whch wll then allow to
calbrate the results of the models and optmze the performance of the sun protectons.
7 CONCLUSION
The objectve of ths artcle s to ntroduce the early stages of the development of the concept of
Varable Façade, whch should be understood as the adaptaton of the derent concepts assocated
wth the reactvty of the façade systems n a partcular socal and economc context such as the
Chlean one. LAPSO, Laboratory of Solar Façade Protectons s ntroduced: a measurement faclty
that wll allowng the development of ths concept based on a methodology that combnes 1: 5 scale
prototypng wth modelng to obtan projected data for the complete year cycle. Prelmnary results
show that, at the typologcal level, the best sun protecton soluton s not the same f the goal s to
optmze solar performance, lght or both at the same tme. LAPSO wll allow the comparson of
these three optons amng to characterze the de-coupled behavor of the llumnaton and the solar
radaton and then manpulate them n a juxtaposed way to obtan the best combnaton of solar,
energetc and lumnous performance.
Acknowledgements
Ths research has been conducted wth fundng from the Natonal Councl of Scentfic and Technologcal Research of Chle
(CONICYT) through FONDEF IDEA ID15I10425 “FACHADA VARIABLE: Solucón de fachada dnámca en base a patrones de
movmento coordnados para el control solar y lumínco aplcable en Santago de Chle”.
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