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Network for Comfort and Energy Use in Buildings, Thermal comfort of occupants during the dry and rainy seasons in Abuja, Nigeria

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Abstract and Figures

The paper presents the results of a recent study on the thermal comfort of occupants in four low-income residential buildings, at two different locations, within the hot-humid climate of Abuja. A comfort survey questionnaire was administered to occupants of four case studies to assess their perception of their thermal environment. Simultaneously, the indoor temperatures and relative humidity of the living room and bedroom spaces were monitored as well as outdoor parameters to evaluate the actual building performance. To support the comfort survey, a post-occupancy survey was carried out to evaluate an additional 86 buildings nearby in the case studies areas. The paper focuses on analysing the thermal conditions of respondents of the post-occupancy survey, the comfort survey and indoor monitoring findings from the case studies. The maximum daytime average temperature of the naturally ventilated buildings was only 2.0°C more than in the air-conditioned buildings. The maximum indoor air temperature in the living spaces during the dry season was 36.8°C (and 26.4% RH) and the minimum 28.4°C (and 66.6% RH), while during the rainy season these were respectively 35.9°C (and 43.7% RH) and the minimum 24.3°C (and 75.5% RH). The results suggest that there was significant thermal discomfort in the low income residential buildings.
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Proceedings+of+9th+Windsor+Conference:+Making'Comfort'Relevant''
Cumberland+Lodge,+Windsor,+UK,+7-10+April+2016.++
Network+for+Comfort+and+Energy+Use+in+Buildings,+http://nceub.org.uk+
+
+
Thermal( comfort( of( occupants( during( the( dry( and( rainy( seasons( in( Abuja,(
Nigeria(
(
Michael'U.'Adaji*,'Richard'Watkins'and'Gerald'Adler'
(
Centre+ for+ Architecture+ and+ Sustainable+ Environment+ (CASE),+ Kent+ School+ of+ Architecture,+
University+of+Kent,+CT2+7NR,+United+Kingdom.+*Corresponding+author:+mua2@kent.ac.uk+
(
Abstract(
The+ paper+ presents+ the+ results+ of+ a+ recent+ study+ on+ the+ therma l+ comfort+ of+ occupants+ in+ four+ low-income+
residential+ buildings,+ at+ two+ different+ locations,+ within+ the+ hot-humid+ climate+ of+ Abuja.+ A+ comfort+ survey+
questionnaire+was+ administered+to+occupants+of+ four+ case+studies+to+assess+their+perception+of+their+thermal+
environment.+Simultaneously,+the+ indoor+temperatures+and+relative+humidity+of+the+living+room+and+bedroom+
spaces+were+monitored+as+well+as+outdoor+parameters+to+evaluate+the+actual+building+performance.+To+support+
the+comfort+survey,+ a+post-occupancy+survey+ was+carried+out+ to+evaluate+an+additional+86+buildings+nearby+ in+
the+ case+ studies+ areas.+ The+ paper+ focuses+ on+ analysing+ th e+ thermal+ conditions+ of+ respondents+ of+ the+ post-
occupancy+ survey,+ the+ comfort+ survey+and+ indoor+ monitoring+ findings+ from+ the+ case+ studies.+ The+ maximum+
daytime+ average+ temperature+ of+ the+ naturally+ ventilated+ buildings+ was+ only+ 2.0°C+ more+ than+ in+ the+ air-
conditioned+ buildings.+ The+ maximum+ indoor+ air+ temperature+ in+ the+ living+ spaces+ during+ the+ dry+ season+ was+
36.8°C+(and+ 26.4%+ RH)+ and+ the+ minimum+ 28.4°C+ (and+ 66.6%+ RH),+while+ during+the+ rainy+ season+ these+ were+
respectively+35.9°C+(and+ 43.7%+ RH)+ and+the+minimum+ 24.3°C+ (and+ 75.5%+RH).+ The+ results+suggest+ that+ there+
was+significant+thermal+discomfort+in+the+low+income+residential+buildings.+
+
Keywords:+Thermal+comfort;+hot-humid+climate;+low-income+residential+buildings+
+
1 Introduction(
Dry+ season+ temperatures+ in+ residential+ buildings+ in+ tropical+ regions+ like+ Nigeria+ are+
becoming+a+major+concern.+High+levels+of+solar+radiation+influence+the+heat+produced+in+this+
region+which+increases+the+heat+intensity+felt+by+residents+within+the+building+as+seen+in+high+
indoor+temperature+levels.+These+indoor+temperatures+can+be+a+health+hazard+and+as+global+
temperatures+ are+ expected+ to+ rise,+ they+ can+ also+ be+ life+ threatening+ to+ occupants.+ Also,+
Indoor+ activities,+ rural+ urban+ migration,+ industrial+ process+ and+ deforestation+ contribute+ to+
the+increase+of+these+high+indoor+temperatures+(Adunola,+2012).++
The+current+high+indoor+temperatures+experienced+ in+ residential+ buildings,+especially+ those+
in+the+big+cities+like+Abuja+in+Nigeria+are+thermally+uncomfortable+for+a+substantial+period+of+
time+(Adunola+and+Ajibola,+2012).+Unfortunately,+the+housing+condition+in+the+country+is+of+
extreme+worry+ as+it+is+largely+of+poor+quality+and+standard+in+both+ rural+ and+urban+centres.+
The+increase+in+the+quantity+of+housing+needs+has+led+to+a+major+and+evident+concern+about+
the+ quick+ deterioration+ of+ current+ housing+ stock+ leading+ to+ a+ shortage+ of+ housing+ units+
(Olayiwola+et+al.,+2005).+Hence,+because+of+the+rush+to+meet+demand,+builders+tend+to+focus+
more+ on+ quantity+ rather+ than+ quality,+ therefore+ compromising+ standards+ and+ indoor+
comfort.+This+in+turn+creates+buildings+with+poor+thermal+properties+i.e.+buildings+that+allow+
high+ levels+ of+ solar+ gain+ into+ the+ building+ fabric,+ subsequently+ increasing+ discomfort+ to+
occupants+ and+ increasing+ the+ energy+ use+ especially+ that+ meant+ for+ cooling+ the+ indoor+
environment.+ Comfort+ levels+ are+ usually+ poor,+ as+ a+ result+ of+ the+ construction+ or+ lack+ of+
ventilation+ in+ the+ roof.+ These+ building+ can’t+ last+ for+ longer+ periods+ before+ they+ start+
deteriorating.++ As+ a+ consequence,+ most+ occupants+ now+ rely+ on+mechanical+ cooling+mostly,+
fan+and+air+conditioning,+to+achieve+thermal+comfort.++
Mechanical+ cooling+ is+ largely+ dependent+ on+ electricity+ in+ Nigeria+ of+ which+ the+ residential+
buildings+ sector+ consumed+ 53.3%+ of+ electricity+ generated+ as+ seen+ in+ the+ Federal+
Government+ of+ Nigeria’s+ 2009+ vision+ 2020+ report+ in+ (Oyedepo,+ 2014);+(Adaji+ et+ al,+ 2015).+
However,+due+ to+ the+ lack+ of+reliable+ and+ continuous+power+ supply+ from+ the+ national+ grid,+
mechanical+ cooling+ systems+ in+ residential+ buildings+ are+ not+ really+ dependable+ to+ provide+
cooling.+Also+ these+ cooling+mechanisms,+ like+ air-conditioning+require+ lots+ of+energy+ to+ run+
and+ maintain.+ Hence,+ the+ continuous+ running+ of+ air-conditioning+ is+ not+ feasible+ and+
sustainable+(Adaji+et+al,+2015).+In+addition+to+the+lack+of+constant+power+supply,+people+tend+
to+turn+to+generators+as+a+back-up+power+supply+for+their+electrical+appliances+especially+for+
mechanical+cooling.++
The+ construction+ and+ building+ sector+ may+ also+ be+ a+ contributing+ factor+ to+ the+ problem+ of+
indoor+heat+gain.+There’s+ little+ or+no+regard+to+ thermal+ comfort+concerns+and+local+ climate+
when+ designing+ and+ constructing+ buildings.+ Most+ materials+ used+ in+ construction+ today,+
especially+the+sandcrete+blocks+for+walling,+made+of+sand,+cement+and+water+mix,+don’t+have+
sunlight+ reflection+ and+ insulation+ qualities.+ Also,+ they+ don’t+ have+ an+ effective+ shield+ or+
insulation+ between+ the+ building+ interior+ and+ the+ outdoor+ environment.+ As+ a+ result,+ the+
building+ through+ its+ opaque+ fabric,+ experiences+ high+ level+ of+ solar+ gain.+ This+ also+ causes+
thermal+discomfort+to+occupants+of+these+buildings+given+the+hot+climate+of+Nigeria+(Adaji+et+
al,+2015).++
A+ thermal+ comfort+ study+ was+ carried+ out+ in+ Abuja,+ with+ a+ view+ to+ understanding+ the+
conditions+of+ residents+ in+ buildings+ across+ two+ different+residential+ neighbourhoods+ in+ the+
city,+during+the+dry+and+rainy+seasons.+This+paper+tries+to+understand+the+ideal+and+preferred+
conditions+ of+ thermal+ comfort+ in+ low-income+ (in+ the+ lower+ half+ of+ the+ income+ spectrum)+
buildings+in+Abuja,+Nigeria.+Furthermore,+monitoring+of+air+ temperatures+ and+ humidity+ was+
carried+ out+ to+ determine+ the+ maximum,+ minimum+ and+ average+ values+ and+ also+ the+ way+
people+ adjust+ to+ achieve+ thermal+ comfort+ in+ buildings+ located+ in+ this+ area+ in+ order+ to+
understand+ what+ residents+ are+ experiencing.+ Studies+ such+ as+ this+ could+ also+ assist+ the+
improvement+ and+ recommendations+ of+ diverse+ levels+ of+ tropical+ comfort+ considerations+
required+in+the+standards+(Djongyang+et+al.+2010).+
2 Conditions(for(achieving(thermal(comfort(in(buildings(
Thermal+ comfort+ can+ be+ described+ as+ satisfaction+ with+ thermal+ sensation+ felt+ within+ an+
indoor+ climate;+ the+ occupants+ in+ their+ indoor+ environment+ should+ be+ satisfied+ with+ their+
indoor+ climate+ of+ the+ time+ (de+ Dear+ and+ Brager,+ 2002).+ For+ people+ to+ find+ a+ building+
thermally+comfortable,+building+designers+should+provide+certain+thermal+comfort+standards+
to+ attain+ or+ improve+ indoor+ climates.+ Occupants+ should+ be+ thermally+ comfortable+ in+ a+
building+ and+ its+ sustainability+ should+ be+ increased+ by+ reducing+ its+ energy+ consumption+
potential+(Nicol+and+Humphreys,+2002).+In+ASHRAE+standard+55+(1992),+it+describes+attaining+
thermal+ comfort+ as+ when+ the+ ‘indoor+ space+ environment+ and+ personal+ factors+ produce+ a+
thermal+ environmental+ condition+ acceptable+ to+ 80%+ or+ more+ of+ the+ occupants+ within+ a+
space’+(ASHRAE+1992;+de+Dear+and+Brager,+2002).+In+thermal+comfort+quality+for+residential+
buildings;+the+materials+used,+nature+of+building,+the+variations+to+the+building+structure+and+
installation+in+all+situations+are+very+important+options+to+use+when+relating+the+influence+of+
changes+to+building,+which+must+be+maintained+at+all+times+(Peeters+et#al.,+2009).++
3 Thermal(comfort(in(a(Hot-humid(climate((
Attaining+thermal+ comfort+is+crucial+for+health+and+efficiency+for+the+people+ in+ the+building.+
Researchers+ have+ used+ indoor+ thermal+ measurements+ such+ as+ ISO+ 7730+ and+ the+ ASHRAE+
standard+ 55+ (ASHRAE,+ 2004)+ to+ determine+ indoor+ thermal+ comfort+ and+ expression+ of+
satisfaction+ by+ that+ condition+ of+ mind+ with+ the+ thermal+ environment.+ The+ results+ and+
analyses+from+these+ experiments+have+created+ thermal+ comfort+templates,+ definitions+ and+
standards+ which+ are+ used+ in+ temperate+ regions;+ after+ all+ it+ was+ developed+ to+ serve+ the+
temperate+climate.++
There+have+been+many+studies+carried+out+in+hot+humid+climates+with+most+results+showing+
a+ wide+ range+ of+ temperatures+ at+ which+ people+ feel+ comfortable+ (comfort+ or+ neutral+
temperature)+ measured+ in+ air-conditioned+ (AC)+ and+ naturally+ ventilated+ (NV)+ buildings+ as+
seen+in+Table+1+below+
+
Table+1:+Neutral+temperature+results+from+field+experiments+conducted+in+hot-humid+climates+
Year(
Researcher(
Building(
Location(
Neutral(temperature(of(subjects(
1990+
J.F+Busch+
Office+
Bangkok,+
Thailand+
24.5°C+(ET)+for+AC+
buildings+
1991+
R.J.+de+Dear,+K.G.+
Leow+et#al.+
Residential+
and+office+
Singapore+
24.2°C+for+AC+
buildings+
1994+
R.J.+de+Dear,+M.E.+
Fountain+
AC+Office+
Townsville,+
Australia+
24.2°C+for+AC+
buildings+
1998+
T.H.+Karyono+
Office+
Jakarta,+
Indonesia+
26.7°C+for+AC+
buildings+
1998+
W.T.+Chan+et#al.+
Office+
Hong+Kong+
23.5°C+for+AC+
buildings+
1998+
A.G.+Kwok+
Classroom+
Hawaii,+USA+
26.8°C+for+AC+
buildings+
2003+
N.H.+Wong+et#al.+
Classroom+
Singapore+
+
Source:+Hwang+et#al.#(2006)+in+Akande+and+Adebamowo,+(2010)+
+
Furthermore,+ studies+ in+ sub-Saharan+ Africa+ have+ shown+ most+ neutral+ temperatures+ are+
above+ 26.0°C+ as+ seen+ in+ Ogbonna+ and+ Harris+ (2007),+ a+ study+ carried+ out+ on+ naturally+
ventilated+buildings+in+Jos,+Nigeria+achieved+an+operative+temperature+of+26.1°C,+though+the+
neutral+ temperature+ was+ 25.06°C.+ Also+ a+ study+ in+ Lagos,+ Nigeria+ by+ Adebamowo,+ (2007)+
achieved+ a+ neutral+ temperature+ of+ 29.1°C.+ In+ Akande+ and+ Adebamowo,+ (2010)+ a+ study+ on+
naturally+ ventilated+ residential+ buildings+ in+ Bauchi,+ Nigeria,+ gave+ a+ neutral+ temperature+ of+
28.4°C.+In+Cameroun,+Djongyang+and+Tchinda,+(2012)+did+a+survey+in+an+inter-tropical+climate+
in+ a+ naturally+ ventilated+ building,+ the+ thermo+ neutral+ temperature+ range+ from+ this+
experiment+was+24.7°C+–+27.3°C.++
From+the+results+ of+studies+conducted+ by+different+researchers+ around+the+world,+ it+ shows+
that+neutral+ temperatures+have+exceeded+the+higher+range+of+ comfort+temperature,+26.0°C+
prescribed+ by+ Fountain+ et+ al.+ (1999)+ and+ the+ ISO+ EN+ 7730+ (1994)+ standard.+ Though+ the+
studies+have+ proven+ to+ be+ important,+ their+ findings+have+ yet+ to+ be+ widely+recognized+ as+a+
comprehensive+way+for+naturally+ventilating+buildings+in+the+tropics+(Adebamowo,+2007).+As+
a+result+of+previous+research+suggestions,+the+wider+range+of+comfort+conditions+in+reality+is+
where+ occupants+ have+ the+ sensation+ of+ feeling+ comfortable.+ Also+ their+ environment+ is+
affected+ by+ several+ factors+ like+ physiological+ adaptations+ (experiences,+ acclimatisation),+
psychological+ adaptations+ (expectations)+ and+ behavioural+ adjustment+ (modifications+ made+
by+a+ person+ consciously+ or+ unconsciously)+which+could+contribute+to+occupants+adapting+to+
changes+(Adebamowo,+2007;+Peeters+et+al.,+2009).++
Regarding+human+thermal+ comfort,+there+has+ been+ much+documented+ material+ worldwide+
from+ physiological,+ adaptive+ and+ social+ hypotheses+ but+ throughout+ sub-Saharan+ Africa+
especially+ the+ tropic+ regions,+ there+ have+ been+ few+ literature+ reports+ on+ comfort+ of+
occupants+and+residential+thermal+environment.+The+tropics+may+require+a+different+level+of+
comfort+ parameter+ in+ the+ standard,+ besides+ the+ current+ standards+ are+ almost+ based+ on+
experiment+ across+ a+ variety+ of+ climatic+ zones+ including+ temperate,+ hot-humid+ and+ cold+
regions+ (Djongyang+ et+ al.+ 2010).+ Furthermore,+ there+ is+ little+ or+ no+ literature+ reported+ on+
indoor+comfort+for+residential+occupants+in+Abuja.++
This+ paper+ is+ aimed+ at+ filling+ this+ gap+ by+ investigating+ the+ indoor+ thermal+ comfort+ for+
occupants+and+their+thermal+environment.++
4 Study(Area(
The+study+area+falls+within+latitudes+7º+20ʹ+and+9º+20ʹ+north+of+the+Equator+and+longitudes+6º+
45ʹ+ and+ 7º+ 39ʹ.+ The+ area+ now+ designated+ the+ Federal+ Capital+ Territory+ (F.C.T.),+ Abuja,+
Nigeria’s+capital,+falls+ within+ the+Savannah+ Zone+ vegetation+of+the+ West+African+sub+ region+
with+Patches+of+rain+forest.+As+it+is+in+the+tropics+Abuja+experiences+two+weather+conditions+
annually;+ the+ rainy+ season+ which+ begins+ in+ April+ and+ ends+ in+ October+ and+ the+ dry+ season+
which+begins+in+October+and+ends+in+April,+but+within+this+period,+there+is+a+brief+interlude+of+
harmattan,+ a+ period+ when+ the+ North+ East+ Trade+ Wind+ moves+ in+ with+ the+ main+ feature+ of+
dust+ haze,+ intensified+ cool+ and+ dryness.+ Fortunately,+ the+ high+ altitudes+ and+ undulating+
terrain+ of+ the+ FCT+ act+ as+ moderating+ influence+ on+ the+ weather+ of+ the+ territory.+ The+
maximum+ daytime+ air-temperature+ ranges+ from+ 28°C+ to+ 35°C+ and+ a+ minimum+ night-time+
temperature+ranging+from+18°C+-+23°C+(World+climate+guide,+2014);+(Abubakar,+2014).(
4.1 Case(Study(Description(
Four+case+studies+in+two+locations+(Lugbe+and+Dutse+Alhaji)+in+Abuja+were+identified+in+order+
to+ investigate+ the+ thermal+ comfort+ of+ occupants+ with+ their+ means+ of+ ventilation+ (natural+
ventilation+ and+ air+ conditioning),+ purpose+ of+ construction+ (for+ low+ income+ group)+ and+
building+type+(low+rise+building)+as+their+main+criteria.++
All+ the+ roofs+ of+ the+ buildings+ selected+ for+ this+ study+ were+ unventilated+ but+ had+ a+ ceiling+
between+the+roof+space+and+the+rooms.+Roof+ overhangs+ were+ in+the+range+of+0.6m+-+0.7m.+
The+floor+to+ceiling+ height+ was+between+3m+ -+ 3.2m.+The+buildings+ were+ all+ventilated+using+
operable+ windows+ and+ none+ of+ the+ external+ windows+ had+ shading+ devices.+ The+ walling+
material+ comprises+ mainly+ sandcrete+ blocks,+ which+ have+ a+ dimension+ of+ 45cm+ x+ 23cm+ x+
23cm+for+external+walls+and+45cm+x+15cm+x+23cm+for+internal+partitions+walls+like+toilets+and+
bathrooms.++
The+case+studies+are+located+in+low+and+low-middle+income+ areas,+ which+ can+ be+ defined+as+
an+area+ where+ residents+ earn+ the+minimum+ wage+ of+ N18,000.00+ (GBP+ 45.00+ at+ N400.00+ =+
GPB+ 1.00)+ to+ four+ times+ the+ minimum+ wage+ (Ekong+ and+ Onye,+ 2013).+ Most+ people+ in+ this+
area+ have+ more+ than+ one+ job+ and+ tend+ to+ save+ over+ time+ to+ build+ or+ rent+ better+ houses,+
therefore+the+ façade+of+ some+of+ these+ houses+ might+ look+ like+ those+ meant+ for+the+ middle+
income+areas,+but+most+ often,+ they+ are+ not+ usually+ built+ to+ the+ recommended+ standard+ set+
by+the+housing+authorities+in+Abuja.++
Case+ study+ 1,+ Lugbe+ (LGH1),+ (Figures+ 1,+ 2+ and+ 3)+ is+ located+ in+ a+ low-middle+ income+ area+
(officially+ designated+ a+ low-income+ area)+ called+ Light+ Gold+ Estate+ just+ off+ the+ express+ way+
linking+the+ international+ airport+in+ Abuja+ to+ the+ city+ centre.+ It’s+ a+north+ facing,+ 3-bedroom+
detached+ bungalow,+ built+ with+ sandcrete+ blocks,+ has+ aluminium+ roofing+ and+ is+ naturally+
ventilated.+
+
Figure+1:+Floor+plan+of+Case+Study+1+in+Lugbe,+Abuja+
+
Figure+2:+Section+A-A+of+Case+Study+1+in+Lugbe,+Abuja+
+
+
Figure+3:+Front+view+of+Case+Study+1+
+
Case+ study+ 2,+ Lugbe+ (LGH2),+ (Figures+ 4+ and+ 5)+ is+ located+ in+ a+ low-middle+ income+ area+ in+
Lugbe+and+it’s+in+the+same+ location+as+the+first+house+only+not+in+the+same+estate+but+north+
of+ the+ first+ case+ study,+ called+ Trade+ Moore+ Estate.+ It’s+ an+ air-conditioned,+ north+ facing+ 2-
bedroom+semi-detached+bungalow,+built+with+sandcrete+blocks+and+has+aluminium+roofing.++
+
Figure+4:+Floor+plan+for+Case+study+2+in+Lugbe,+Abuja+
+
(
Figure+5:+Main+building,+Case+study+2+
+
Case+ study+ 3+ (DAH1)+ in+ Dutse+ Alhaji,+ (Figures+ 6,+ 7+ and+ 8)+ is+ located+ in+ a+ low-income,+ high+
density+area.+The+building+is+naturally+ventilated+and+has+a+painted+exterior.+It+is+roofed+with+
iron+ sheets+ and+ built+ with+ sandcrete+ blocks.+ It’s+ in+ a+ sound+ state,+ although+ it+ needs+ some+
minor+repairs.+Finally,+Case+study+4+(DAH2)+(Figures+6+and+8)+is+located+in+the+same+area+and+
is+a+1+bedroom+flat+attached+to+DAH1.+It+is+air+conditioned+and+it’s+also+in+a+sound+state+but+
needs+minor+repairs+too.+
+
+
Figure+6:+Floor+plan+for+Case+studies+3+and+4+in+Dutse+Alhaji,+Abuja+
+
+
Figure+7:+Section+B-B+of+the+Case+Study+3+in+Dutse+Alhaji,+Abuja+
+
Figure+8:+Main+building,+Case+studies+3+and+4+in+Dutse+Alhaji,+Abuja+
5 Research(methods(and(techniques(used(for(this(research(
The+ methodology+ for+ the+ survey+ included+ environmental+ monitoring,+ with+ post-occupancy+
and+ comfort+ surveys.+ These+ surveys+ were+ aimed+ at+ obtaining+ a+ comprehensive+
understanding+of+occupants’+thermal+comfort+sensation+within+the+buildings+and+occupants’+
energy+demands+and+use.++
+
5.1 Post-occupancy(Survey(
Post-occupancy+ surveys+ help+ understand+ and+ compare+ the+ nature+ and+ frequency+ of+
occupants’+views+that+cannot+be+measured+during+surveys,+especially+why+they+feel+warm+or+
hot.+That’s+why+they+are+critical+in+increasing+the+value+of+the+thermal+environment,+(Nicol+&+
Roaf,+ 2005);+ (Adekunle+ and+ Nikolopoulou,+ 2014).+ This+ survey+ focused+ on+ dwellings+ other+
than+the+ case+study+buildings+but+situated+in+the+same+area.+They+add+breadth+and+support+
the+results+ from+ the+individual+case+studies.+Each+questionnaire+in+the+current+study+has+ 31+
questions,+ requiring+ 8-10+ minutes+ to+ complete.+ Questions+ on+ overall+ thermal+ comfort+ and+
thermal+ satisfaction+ in+ different+ seasons+ were+ asked+ for+ respondents+ to+ evaluate.+ The+
questionnaire+ was+ divided+ into+ three+ main+ sections:+ Section+ A,+ includes+ background+
information+ about+ their+ location,+ gender,+ age,+ socio-economic+ status,+ educational+ and+
occupancy+ status;+ Section+ B,+ asks+ about+ building+ attributes+ and+ energy+ consumption+
including+house+type,+number+of+rooms+in+the+building+and+duration+of+occupancy;+Section+C,+
considers+ indoor+ thermal+ conditions+ and+ looks+ at+ how+ residents+ make+ themselves+
comfortable+ by+ opening+ and+ closing+ windows+ or+ doors,+ and+ clothing+ type.+ Overall+ 109+
questionnaires+ were+ distributed,+ 100+ (92%)+ were+ returned+ and+ of+ these+ 86+ (79%)+ were+
correctly+ completed.+ The+ questionnaires+ were+ self-administered+ and+ survey+ visits+ were+
conducted+between+6.30am+and+18.00pm+(Figure+9).+
+
+
++ +
Figure+9:+Post+occupancy+survey+
5.2 Comfort(Survey(
Thermal+comfort+questionnaires+ were+ issued+to+the+ occupants+ of+the+dwellings+ monitored.+
They+were+asked+to+complete+the+questionnaires+three+times+per+day+to+assess+their+thermal+
comfort+ state,+ (using+ the+ seven-point+ ASHRAE+ thermal+ sensation+ scale+ and+ a+ five-point+
preference+scale).+Further+information+on+clothing+insulation+and+activity+was+also+collected.+
The+ comfort+ survey+ was+ designed+ as+ a+ daily+ diary+ evaluating+ occupants’+ responses+ to+
discomfort+and+how+ they+ achieve+comfort+at+ various+ times+of+the+ day+ (morning,+afternoon+
and+evening)+for+a+week.+These+data+were+used+to+support+the+physical+data+collected+at+the+
same+time.++
+
5.3 Environmental(Monitoring(
The+field+survey+was+conducted+during+the+dry+and+rainy+seasons+from+18/03/15+to+18/04/15+
and+ 17/06/15+ to+ 12/07/15+ respectively.+ Air+ temperature+ and+ relative+ humidity+ were+
recorded+using+HOBO+Temperature+and+ Relative+ Humidity+sensors+installed+on+ the+ internal+
walls+ at+ a+ height+ of+ 1.1m+ above+ the+ ground+ floor+ level.+ Four+ dwellings+ were+ monitored+ in+
Abuja,+with+ two+ spaces+representing+ the+ living+area+ and+ bedroom+ area+ monitored+ in+ each+
case+ study.+ The+ outdoor+ environmental+ conditions+ measured+ were+ air+ temperature+ and+
relative+humidity+ using+ Tiny+Tag+ T/RH+sensors+ inside+ a+ radiation+ shield.+Data+ was+recorded+
every+15+minutes+(Figure+10).+
+
++++++++++++++++++++ +
Figure+10:+Installation+of+Tiny+Tag+outdoor+logger+and+indoor+Hobo+T/RH+sensors++
6 Data(analysis(and(Results(
6.1 Analysis(of(Post-Occupancy(Survey(
Lugbe+had+43+ valid+questionnaires+ returned+(79%+ response),+of+ which+ 26+(60.5%)+ were+male+
and+17+female+(39.5%).+Most+of+the+respondents+were+from+the+(31-45)+age+group,+24+(55.8%)+
and+17+(39.5%)+from+the+(18-30)+age+group.+Dutse+Alhaji+had+43+valid+questionnaires+returned+
(80%+ response),+ with+ 33+ (76.7%)+ male+ and+ 10+ (23.3%)+ female+ responses.+ The+ age+ response+
breakdown+was+33+(76.7%)+for+the+(31-45)+and+10+(23.3%)+from+the+(18-30)+age+group.+
In+the+ dry+ season,+ the+ warm+ part+ of+ the+scale+ had+ a+much+ greater+ response+ across+ all+ the+
respondents+of+ the+ case+ studies,+ with+ 74.4%+ of+occupants+ feeling+‘warm’+ or+‘hot’+ at+ Lugbe+
and+86.1%+at+Dutse+Alhaji+(figure+11).+In+contrast,+in+the+rainy+season,+there+was+a+clear+shift+
to+the+ ‘cool’+part+of+the+scale+for+respondents+in+ Lugbe+with+more+than+67.0%+feeling+‘cool’+
or+ ‘slightly+ cool’,+ whilst+ 52.9%+ of+ respondents+ in+ Dutse+ Alhaji+ felt+ ‘cool’,+ ‘slightly+ cool’+ or+
‘neutral’+(figure+ 12).+ The+mean+ thermal+ sensations+ for+ Lugbe+ and+ Dutse+ Alhaji+ (Table+ 2)+in+
the+ dry+ season+ were+ around+ the+ ‘slightly+ warm’+ and+ ‘warm’+ while+ in+ the+ rainy+ season+
between+ ‘cold’+ and+ ‘neutral’.+ The+ overall+ thermal+ sensation+ results+ across+ the+ two+ case+
studies+show+that+80.2%+felt+either+‘warm’+or+‘hot’+during+the+dry+season+compared+to+29.1%+
that+felt+‘slightly+warm’+or+‘warm’+during+the+rainy+season+
++ +
Figure+11:+Distribution+of+overall+thermal+sensation+votes+during+the+dry+season+in+Lugbe+(left)+and+Dutse+Alhaji+
(Right)+(Scale:+1+=+Cold+to+7+=+Hot)+
+++ +
Figure+12:+Distribution+of+overall+thermal+sensation+votes+during+the+rainy+season+in+Lugbe+(left)+and+Dutse+
Alhaji+(right)+(Scale:+1=+cold+to+7=+hot)+
Table+2:+Post+occupancy+survey+mean+responses+for+the+overall+thermal+sensation,+thermal+satisfaction,+overall+
thermal+comfort+in+the+dry+and+rainy+season++
Case(study(
+
Overall(Thermal(sensation(
(Scale:+1=+cold+to+7=+hot)(
Thermal(satisfaction(
(Scale:+very+dissatisfied+to+7=+
very+satisfied.)(
Overall(thermal(comfort(
(Scale:+ 1+ =+ very+ comfortable+
to+7=+very+comfortable)(
Dry+season+
Rainy+season+
Dry+season+
Rainy+season+
Dry+season+
Rainy+season+
Lugbe+
5.8+
2.9+
3.9+
5.4+
3.6+
2.5+
Dutse+Alhaji+
6.0+
4.2+
2.1+
3.3+
5.3+
3.9+
+
The+thermal+satisfaction+was+measured+on+a+7-point+scale+with+1+for+very+dissatisfied+to+7+for+
very+satisfied.+In+Lugbe,+37.2%+ were+ satisfied+with+their+thermal+environment+ compared+ to+
90%+ of+ respondents+ of+ Dutse+ Alhaji+ that+ were+ either+ ‘very+ dissatisfied’,+ ‘dissatisfied’+ or+
‘slightly+dissatisfied’+(Figure+13).++
++ +
Figure+13:+Distribution+of+thermal+satisfaction+votes+during+the+rainy+season+in+Lugbe+(left)+and+Dutse+Alhaji+
(right)+(Scale:+1=+very+dissatisfied+to+7=+very+satisfied.)+
+
A+7-point+scale+(from+ 1+ for+ very+ uncomfortable+to+7+for+very+comfortable)+was+used+for+the+
overall+ thermal+ comfort.+ There+ was+ an+ almost+ even+ distribution+ of+ the+ comfort+ votes+ in+
Lugbe+ where+ 49.5%+ were+ dissatisfied,+ i.e.+ only+ slightly+ skewed+ towards+ discomfort.+
However,+81%+ of+ the+respondents+ in+ Dutse+Alhaji+ indicated+they+ were+ uncomfortable+with+
their+thermal+environment+(Figure+14).+These+results+suggest+that+the+thermal+environment+
has+ been+ influenced+ by+ the+ air-conditioning+ in+ these+ buildings+ especially+ in+ Lugbe,+ where+
65.1%+use+air-conditioning+in+their+living+rooms+and+58.1%+in+their+bedroom+while+in+Dutse+
Alhaji,+37.2%+use+air-conditioning+in+their+living+room+and+30.2%+in+their+bedroom,+indicating+
Lugbe+has+more+air-conditioning+users+compared+to+those+in+Dutse+Alhaji.+
For+the+rainy+season,+the+respondents+in+Lugbe+showed+a+substantial+shift+in+overall+thermal+
comfort+vote+towards+the+comfort+part+of+the+scale,+with+76.7%+feeling+‘slightly+comfortable’+
or+ ‘comfortable’,+ while+ 58.1%+ of+ respondents+ in+ Dutse+ Alhaji+ were+ ‘neutral’,+ ‘slightly+
comfortable’+or+‘comfortable’+(Figure+15).+
+
Figure+14:+Distribution+of+overall+thermal+satisfaction+votes+during+the+dry+season+in+Lugbe+(left)+and+Dutse+
Alhaji+(right)+(Scale:+1=+very+uncomfortable+to+7=+very+comfortable)+
+
+ +
Figure+15:+ Distribution+ of+ overall+ thermal+satisfaction+ votes+ during+ the+ rainy+season+in+Lugbe+(left)+and+ Dutse+
Alhaji+(right)+(Scale:+1=+very+uncomfortable+to+7=+very+comfortable)+
+
6.2 Analysis(of(Comfort(Survey(
105+thermal+ comfort+questionnaires+were+administered+during+the+dry+season+and+71+ were+
received+ (67.6%+ response),+ while+105+ were+ administered+ during+ the+ rainy+ season+ and+ 55+
were+received,+(52.4%+response).+
The+ comfort+ surveys+ (Figures+ 16+ and+ 17)+ show+ most+ of+ the+ occupants+ were+ feeling+ warm+
with+ most+ of+ the+ distribution+ of+ votes+ varying+ from+ ‘slightly’+ warm’+ to+ ‘hot’.+ The+ results+
suggest+that+50%+of+the+time+the+occupants+in+Lugbe+LGH1+felt+‘warm’+while+25%+of+the+time+
occupants+in+ Lugbe+ LGH2+ felt+ ‘warm’.+ Also,+ 77%+of+ the+ time+ the+ occupants+ in+ Dutse+Alhaji+
DAH1+felt+ ‘warm’+compared+to+25%+of+the+time+in+Dutse+ Alhaji+DAH2.+The+25%+warm+votes+
recorded+in+ Lugbe+ LGH2+ and+ Dutse+ Alhaji+ DAH2+ can+ be+ attributed+ to+ the+ use+ of+ air-
conditioning+in+these+dwellings.++
The+ majority+ of+ the+ residents+ spent+ 12+ hours+ inside+ the+ house+ per+ day+ and+ most+ of+ the+
participants+from+ the+survey+have+lived+in+the+ case+study+buildings+for+over+36+ months.+The+
residents+ in+ Lugbe+ owned+ the+ properties+ they+ live+ in+ while+ the+ occupants+ in+ Dutse+ Alhaji+
lived+in+rented+buildings.++
+
+
Figure+16:+Distribution+of+overall+thermal+sensation+votes+during+the+dry+season+in+Lugbe+with+naturally+
ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+cold+to+7=+hot)+
+
+
Figure+17:+Distribution+of+overall+thermal+sensation+votes+during+the+dry+season+in+Dutse+Alhaji+with+naturally+
ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+cold+to+7=+hot)+
+
There+was+a+shift+ in+the+thermal+sensation+ mean+ votes+during+the+ rainy+ season+to+the+ cool+
and+neutral+part+of+the+scale+(Figures+18+and+19).+More+than+67%+of+the+time+the+residents+in+
Lugbe+felt+either+‘slightly+cool’+or+‘neutral’+or+‘slightly+warm’+compared+to+more+than+88%+of+
the+time+in+Dutse+Alhaji+that+either+felt+‘neutral’+or+‘slightly+cool’.+The+results+further+suggest+
that+ most+ of+ the+ time+ the+ residents+ in+ the+ case+ studies+ in+ Dutse+ Alhaji+ felt+ warmer+ in+ the+
rainy+season+compared+to+residents+in+Lugbe.+
+
Figure+18:+Distribution+of+overall+thermal+sensation+votes+during+the+rainy+season+in+Lugbe+with+naturally+
ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+cold+to+7=+hot)+
+
+
Figure+19:+Distribution+of+overall+thermal+sensation+votes+during+the+rainy+season+in+Lugbe+with+naturally+
ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+cold+to+7=+hot)+
+
Table+3:+Comfort+survey+mean+responses+for+the+thermal+sensation+and+thermal+satisfactions+in+the+dry+and+
rainy+season++
Case(study(
+
Thermal(sensation(
(Scale:+1=+cold+to+7=+hot)(
Thermal(preference(
(Scale:+1=+much+cooler+to+5=+much+
warmer)(
Dry+season+
Rainy+season+
Dry+season+
Rainy+season+
Lugbe+LGH1+(NV)+
5.4+
2.9+
2.1+
3.1+
Lugbe+LGH2+(AC)+
5.0+
3.0+
2.3+
4.4+
Dutse+Alhaji+DAH1+(NV)+
5.9+
3.0+
1.6+
2.5+
Dutse+Alhaji+DAH2+(AC)+
5.0+
4.0+
2.3+
3.2+
NV:+naturally+ventilated+building,+AC:+air-conditioned+building+
+
Figure+20:+Distribution+of+overall+thermal+preference+votes+during+the+dry+season+in+Lugbe+with+naturally+
ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+much+cooler+to+5=+much+warmer)+
+
+
Figure+21:+Distribution+of+overall+thermal+preference+votes+during+the+dry+season+in+Dutse+Alhaji+with+naturally+
ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+much+cooler+to+5=+much+warmer)+
+
The+ mean+ distributions+ of+ occupants’+ responses+ from+ the+ dry+ season+ surveys+ shows+ they+
would+ prefer+ to+ be+ cooler+ (Figure+ 20-23).+ Also+ there+ was+ a+ drift+ to+ the+ ‘no+ change’+ vote+
during+ the+ rainy+ season.+ The+ survey+ indicates+ that+ most+ occupants+ prefer+ their+ thermal+
environment+the+way+it+is+during+the+rainy+season+(Table+3).+
+
+++ +
Figure+22:+Distribution+of+overall+thermal+preference+votes+during+the+rainy+season+in+Lugbe+with+naturally+
ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+much+cooler+to+5=+much+warmer)+
+
+
Figure+23:+Distribution+of+overall+thermal+preference+votes+during+the+rainy+season+in+Dutse+Alhaji+with+
naturally+ventilated+building+(left)+and+air-conditioned+building+(right)+(Scale:+1=+much+cooler+to+5=+much+
warmer)+
+
6.3 Analysis(of(Environmental(Survey(
The+outdoor+ temperature+ recorded+in+ Lugbe+ during+ the+ dry+ season+ varied+ from+ 23.0ᵒC+ on+
19/3+to+a+maximum+of+41.7ᵒC+on+21/3,+with+a+relative+humidity+varying+from+17.8%+on+19/3+
to+ a+ maximum+ of+ 93.1%+ on+ 21/3,+ and+ an+ average+ of+ 56%+ (Figure+ 24);+ while+ the+ outdoor+
temperature+in+ Dutse+ Alhaji+varied+ from+23.0ᵒC+ on+ 15/4+to+ a+maximum+ of+ 38.0ᵒC+on+15/4,+
with+a+ relative+humidity+varying+from+35.4%+on+14/4+to+a+maximum+of+94%+on+ 15/4+and+an+
average+of+35.4%+throughout+the+monitoring+period+(Figure+25).++
!
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+
Figure+24:+Outdoor+temperature,+running+mean+of+daily+average+temperature+and+relative+humidity+during+the+
dry+season+monitoring+in+Lugbe+
+
!
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+
Figure+25:+Outdoor+temperature,+running+mean+of+daily+average+temperature+and+relative+humidity+during+the+
dry+season+monitoring+in+Dutse+Alhaji+
+
The+ rainy+ season+ recorded+ an+ outdoor+ temperature+ that+ varied+ from+ 21.0ᵒC+ on+ 17/6+ to+ a+
maximum+of+ 31.0ᵒC+on+ 23/6+in+Lugbe,+with+a+relative+humidity+varying+from+55.4%+ on+23/6+
to+a+ maximum+ of+ 99.9%+ on+22/6,+ and+ an+ average+ of+81.8%+ (Figure+ 26);+ while+ the+outdoor+
temperature+in+Dutse+Alhaji+varied+from+20.5ᵒC+on+5/7+to+a+maximum+of+32.9ᵒC+on+7/7,+with+
a+ relative+ humidity+ varying+ from+ 45.9%+ on+ 11/7+ to+ a+ maximum+ of+ 98.7%+ on+ 5/7+ and+ an+
average+of+75%+throughout+the+monitoring+period+(Figure+27).++
!"#
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;.7<.=016=.4ºC
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+
Figure+26:+Outdoor+temperature,+running+mean+of+daily+average+temperature+and+relative+humidity+during+the+
rainy+season+monitoring+in+Lugbe+
+
!"
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>507??<30-6;-</05<- ,5@@1@A36-/@30-6;-<0/5<- ,-./012-3B5617108
+
Figure+27:+Outdoor+temperature,+running+mean+of+daily+average+temperature+and+relative+humidity+during+the+
rainy+season+monitoring+in+Dutse+Alhaji+
+
The+measured+outdoor+ temperature+ had+a+ running+ mean+temperature,+Trm,+ (Figures+ 24-26)+
as+defined+by+BSENI+15251+(BSI,+2008),+varying+from+30.6ᵒC+on+18/3+to+a+maximum+of+33.3ᵒC+
on+21/3+ in+Lugbe+and+30.8ᵒC+11/4+and+a+ maximum+of+31.4ᵒC+on+17/4+in+Dutse+Alhaji+during+
the+dry+season+monitoring.+The+results+suggest+that+Lugbe+had+the+hottest+month+of+the+year+
(March),+with+an+average+outdoor+monthly+temperature+of+33.9ᵒC+and+a+maximum+outdoor+
temperature+of+41.7ᵒC+on+19/3.+
The+average+indoor+temperature+between+08.00+and+22.00+in+the+monitored+living+areas+in+
Lubge+ was+ 32.2ᵒC+ for+ the+ living+ rooms+ and+ 32.1ᵒC+ for+ the+ bedrooms.+ The+ living+ rooms+
recorded+ the+ hottest+ temperature+ in+ the+ building+ with+ a+ mean+ of+ 32.5ᵒC+ and+ a+ maximum+
temperature+of+36.2ᵒC.+The+average+ temperature+ between+ 23.00+and+07.00+was+ 31.3ᵒC+for+
the+living+rooms+and+31ᵒC+for+the+bedrooms.+ The+living+rooms+were+also+the+hottest+spaces+
in+the+buildings+with+a+mean+temperature+of+31.1ᵒC+(Figure+28).+
+
!"
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*+,-+./01.+234
5/0+
610788.20+,-+./01.+ 91::;:<2,+/: =;>;:<2.88,2=?@'
A+7.88,2=?@' =;>;:<2.88,2=?@! A+7.88,2=?@!
+
Figure+28:+Living+rooms+and+bedrooms+monitored+in+two+different+buildings+in+Lugbe+during+the+dry+season+
+
In+Dutse+Alhaji,+the+average+indoor+temperature+between+08.00+and+22.00+in+the+monitored+
living+areas+in+Dutse+Alhaji+was+34.4ᵒC+for+the+living+rooms+and+31.1ᵒC+for+the+bedrooms.+The+
living+room+space+recorded+ the+ hottest+temperature+in+ the+ building+with+a+ mean+ of+34.5ᵒC+
and+a+maximum+temperature+of+36.8ᵒC.+The+average+temperature+between+23.00+and+07.00+
was+32.7ᵒC+for+the+living+rooms+and+31.3ᵒC+for+the+bedrooms.+The+living+rooms+also+were+the+
hottest+spaces+in+the+buildings+with+a+mean+temperature+of+32.9ᵒC+(Figures+29).+
The+ results+ indicate+ the+ living+ room+ is+ the+ hottest+ monitored+ space+ in+ the+ buildings+ and+
occupants+in+ Dutse+ Alhaji+ experienced+ higher+ temperatures+ compared+to+ the+ occupants+ in+
Lugbe.+++
More+than+90%+of+the+spaces+monitored+during+the+dry+season+in+all+case+studies+recorded+
temperatures+ above+ the+ (ISO+ EN7730,+ 1994)+ standard+ for+ sedentary+ activities+ which+
specified+a+23ᵒC+and+26ᵒC+temperature+range.+The+indoor+ relative+ humidity+ was+21%+-+76%+
for+Lugbe+and+15%+-+66%+in+Dutse+Alhaji,+which+was+outside+the+(ISO+EN7730,+1994)+standard+
range+ of+ 30%+ -+ 70%+ for+ the+ associated+ temperatures.+ However,+ the+ maximum+ relative+
humidity+recorded+in+Lugbe+was+within+the+range.++
+
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+,-.,/012/,3ºC
401,
521677/31,-.,/012/, 8299:9;3-,0931,-.,/012/, <:=:9;3/77-34>?'
@,6/77-34>?' <:=:9;3/77-34>?! @,6/77-34>?!
+
Figure+29:+Living+rooms+and+bedrooms+monitored+in+two+different+buildings+in+Dutse+Alhaji+during+the+dry+
season+
+
During+ the+ rainy+ season+ survey,+ the+ temperature+ range+ of+ 25ᵒC+-+30ᵒC+(Figure+ 30),+ with+ a+
relative+humidity+range+of+29%+-+91%+was+recorded+in+the+living+room+spaces+in+Lugbe+while+
a+temperature+ range+ of+ 27ᵒC+–+35.9ᵒC+(Figure+31),+ with+a+ relative+humidity+ range+of+ 40%+-+
87%+was+recorded+in+the+living+spaces+in+Dutse+Alhaji.++
+
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@,6/77-3<>?! <:=:9;3/77-3<>?# @,6/77-3<>?#
+
Figure+30:+Living+rooms+and+bedrooms+monitored+in+two+different+buildings+in+Lugbe+during+the+rainy+season+
+
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512-
632788042-./-01230- 93::;:<4.-1:42-./-01230- =;>;:<4088.45?@!
A-7088.45?@! =;>;:<4088.45?@# A-7088.45?@#
+
Figure+31:+Living+rooms+and+bedrooms+monitored+in+two+different+buildings+in+Dutse+Alhaji+during+the+rainy+
season+
7 Conclusions(
The+ results+ from+ the+ post+ occupancy,+ environmental+ monitoring+ and+ comfort+ survey+ from+
different+ residential+ low-income+ buildings+ in+ Abuja,+ Nigeria+ were+ presented+ in+ this+ paper.+
Across+ the+ different+ locations+ examined+ during+ the+ post+ occupancy+ evaluations,+ 80%+
reported+being+warm+and+hot+on+the+thermal+sensation+scale+with+most+reporting+being+‘not+
satisfied’+with+their+thermal+indoor+environment.+At+least+50%+were+uncomfortable+with+the+
thermal+ condition.+ This+ further+ suggests+ that+ occupants+ perceived+ higher+ indoor+
temperatures+during+the+dry+season.+
A+ different+ perspective+ was+ provided+ with+ the+ comfort+ survey,+ as+ most+ of+ the+ time+ the+
monitored+occupants+in+the+naturally+ventilated+ buildings+ felt+hotter+than+the+occupants+in+
the+air-conditioned+ buildings.+ More+ than+ 70%+of+ the+ time+ the+ occupants+in+ the+ monitored+
case+studies+felt+either+‘slightly+warm’+or+‘warm’+most+of+the+time+when+they+were+indoors.++
The+maximum+outdoor+temperature+and+relative+humidity+recorded+was+41.7ᵒC+and+99.9%,+
with+ the+ naturally+ ventilated+ buildings+recording+ the+ highest+ and+ lowest+ temperatures+ of+
36.8ᵒC+and+24.3ᵒC+in+the+living+rooms+in+Lugbe+and+Dutse+Alhaji.+However,+the+difference+in+
temperature+between+the+air+conditioned+ and+ naturally+ventilated+building+was+ only+ about+
2ᵒC.+Most+of+the+occupants+do+not+find+their+thermal+conditions+acceptable+and+more+than+
80%+ of+ the+ spaces+ monitored+ in+ all+ case+ studies+ recorded+ temperatures+ above+ the+ (ISO+
EN7730,+1994)+standard+for+sedentary+activities.+
The+ results+ suggest+ that+ most+ residents+ in+ the+ study+ areas+ of+ Abuja+ are+ not+ satisfied+ with+
their+thermal+environment+and+there+is+discomfort+among+occupants+in+residential+buildings.+
Occupants+ prefer+ to+ be+ much+cooler+ during+ the+ dry+ season,+ therefore+ there+ is+ high+
dependence+on+air-conditioning+to+improve+their+thermal+condition.++
However,+air-conditioning+ is+ not+used+ as+much+ as+ it+ might+ be+because+ of+continual+ power-
cuts,+the+ cost+ and+ noise+ of+ running+ generators+ and+ personal+security+ issues.+This+ is+a+ good+
reason+for+trying+to+improve+the+construction+of+the+dwellings+so+that+they+are+made+to+be+
comfortable+ using+ more+ passive+ means.+ This+ paper+ has+ reported+ on+ four+ case+ study+
dwellings,+but+six+further+dwellings+have+since+been+monitored+in+detail+and+will+be+reported+
in+the+future.+
Acknowledgements(
This+ study+ was+ privately+ funded+ by+ Mr+ O.+ P.+ S.+ Adaji+ and+ supported+ by+ The+ Centre+ for+
Architecture+and+Sustainable+Environment+(C.A.S.E.),+Kent+School+of+Architecture,+University+
of+Kent,+ UK.+ Their+ dependable+ support+ made+ this+ study+successful.+ We+ are+ grateful+ to+the+
residents+of+ the+ case+ studies,+ especially+those+ that+ allowed+ us+ access+into+ their+ homes+ for+
monitoring,+and+for+their+undue+support+during+the+period+of+this+survey+we+thank+them+all.+
References(
Abubakar+I.R.,+2014.+Abuja,+city+profile,+Cities#41+(2014),+pp+8191.+
Adaji,+ M.,+ Watkins,+ R.+ and+ Adler,+ G.,+ 2015.+ An+ investigation+ into+ thermal+ comfort+ in+
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... In addition, the study conducted by(M. Adaji, Watkins, and Adler 2016), showed that the occupants of the studied buildings in Abuja, Nigeriaare not satisfied with the thermal environment of their living places. In another study, (Yu et al. 2017) showed that the thermal comfort temperature range is acceptable for residential buildings produced in Tibet region of China. ...
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