Guidelines for Design with Climate in the Coastal Zone of
Nigeria: Implications for prototype mass housing.
By
Alelumhe Jeremiah Irhenaye
Arc/05/5593
Department of Architecture
Federal University of Technology, Akure
In Partial Fulfilment of the course
Applied Climatology (Arc 810)
Course Lecturer: Prof.Ogunsote.O.O
August, 2011
1
TABLE OF CONTENTS
1.0 Introduction
2.0 Characteristics Of The Coastal Zone
2.1 The Use Of Surfer Software In Analysing Rainfall Pattern for the Coastal Zone
3.0 Case Study-Proto Type Mass Housing At Unilag
3.1 Background of Case Study
3.2 Implications of design guidelines for Prototype Mass Housing
4.0 Conclusion
2
1.0 INTRODUCTION
The coastal zone which is one among the six zones in Nigeria climatic zones is highly
characterised with high amount of rainfall since most of the states found here are located
along the coastal bank of the atlantic ocean and this have resulted to its high level of rainfall
and humidity.In achieving and establishing workable guidelines for the designs especially of
prototype mass housing in nature, a careful consideration should be taken to ensure a design
that will be able to combact the twin elements of high amount of rainfall and heated up hours.
This guidelines should span through the choice of materials to be used in the various
elements of the building,size of openings,orientation of buildings,position of openings and
lots more to be able to produce a design that is green in attribute,environmental friendly,and
promote human comfort.
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2.0 CHARACTERISTICS OF THE COASTAL ZONE
The coastal zones which includes cities such as Ikeja,Lagos,Ondo,Benin,Warri,Portharcourt
and Calabar is highly characterised with high humidity and hot discomfort for eleven or more
months in the year which makes the provision of permanent ventilation essential.The monthly
rainfall exceeds 200mm for three or more months in a year and the table below confirms that
for the mean range of temperatures of cities in the coastal zones for the span of 29 years
hence a high level of design shading away rainfall is necessary in this zones and there is a
high need to inculcate self drained systems that will channel this water appropriately or
recycles the water for household use.There is no need for thermal storage as high diurnal
temperature range of more than 10 degrees coupled with low humidity is not experienced for
more than one month in the year and the monthly maximum temperature never falls below
the comfort limit,thus no special precautions need be taken against cold discomfort.
Fig 1:Chart showing the linear trend of rainfall for the coastal zone having the higest
range of rainfall
450.00
TIME SERIES WITH LINEAR TRENDS OVER THE
STATIONS (1978-2007)
400.00
MAR
JUN
SEP
350.00
Linear (SEP)
300.00
RAINFALL (mm)
R² = -1.674
250.00
200.00
150.00
100.00
0.00
calabar
yola
yelwa
warri
kaduna
umua…
birni-…
bida
akure
bauchi
lokoja
kano
maidu…
sokoto
potisk…
minna
mokwa
ibadan
onne
samaru
sado
owerri
osogbo
nguru
mubi
makurdi
jos
abuja
50.00
4
NO
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
LONGITUDE LATITUDE STATIONS
8.31442 4.95729 calabar
5.2
7.25 akure
7.483333 5.533333 umuahia
7.15 4.716667 onne
5.75368 5.50995 warri
4.56122 7.76581 osogbo
3.89528 7.37884 ibadan
7.233333 5.483333 nguru
8.52309 7.74734 makurdi
6.733333
7.8 lokoja
7.033333 5.483333 owerri
6.016667 9.083333 bida
6.55 9.616667 minna
5.05 9.283333 mokwa
12.866667 10.383333 yola
4.2 12.466667 birni-kebbi
11.066667 11.716667 potiskum
13.16109 11.85063 maiduguri
5.24574 13.05702 sokoto
6.166667 12.416667 sado
13.266667 10.266667 mubi
9.84517 10.30982 bauchi
7.633333 11.166667 samaru
9.783333 10.283333 yelwa
7.44312 10.51901 kaduna
8.516667 11.996389 kano
7.26572 9.00536 abuja
8.89339
9.9244 jos
ZONES
data
Coastal
Coastal
Coastal
Coastal
Coastal
FOREST
FOREST
TRANSITION
TRANSITION
TRANSITION
TRANSITION
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
SAVANNAH
HIGHLAND
STATE
1 CROSS RIVER
1 ONDO
1 ABIA
1 RIVERS
1 DELTA
3 OSUN
3 OYO
5 IMO
5 BENUE
5 KOGI
5 IMO
7 NIGER
7 NIGER
7 NIGER
7 ADAMAWA
7 KEBBI
7 YOBE
7 BORNO
7 SOKOTO
7 ZAMFARA
7 ADAMAWA
7 BAUCHI
7 KADUNA
7 BAUCHI
7 KADUNA
7 KANO
7 FCT
9 PLATEAU
MeanRR JAN
2909.85
1405.37
2014.90
2413.54
2792.41
1141.60
1310.39
453.52
1181.15
1211.78
2189.20
1166.52
1156.70
936.69
914.72
617.69
601.03
530.04
657.57
597.20
998.22
972.00
1019.15
964.29
1267.59
749.15
1307.14
1265.62
FEB
25.78
7.12
16.17
17.16
23.66
5.74
3.68
0.13
6.32
2.73
17.55
2.85
0.79
0.45
0.04
0.00
0.00
0.03
0.03
0.00
0.00
0.00
0.03
0.06
0.48
0.06
1.29
0.30
43.91
37.07
46.49
42.99
50.28
13.84
21.80
0.19
1.68
6.59
32.06
4.01
0.02
0.63
0.00
0.00
0.00
0.03
0.09
0.26
0.61
0.02
0.21
0.62
0.82
0.88
4.24
2.90
MAR
144.93
76.27
129.78
136.63
126.62
44.72
77.05
1.34
24.59
36.04
103.67
16.78
9.65
5.50
5.31
0.03
0.10
0.04
3.31
2.61
18.47
4.05
5.08
9.02
13.83
1.45
38.29
18.03
APR
230.57
144.71
236.42
164.21
211.90
81.63
123.13
4.01
87.56
104.05
153.02
70.51
60.37
57.34
55.75
9.49
6.86
5.98
9.82
17.84
34.37
32.42
44.24
37.19
69.76
7.56
61.43
85.93
MAY
278.02
166.41
223.12
254.93
262.07
118.04
160.06
15.27
149.58
162.26
224.05
140.54
133.58
99.67
104.78
24.97
27.84
36.79
42.83
49.87
85.56
107.84
101.58
93.75
128.45
49.41
155.71
168.97
JUN
410.53
198.50
293.75
303.23
336.08
149.82
176.02
57.02
197.24
166.34
292.21
156.94
168.46
138.93
134.14
90.38
79.62
63.56
95.53
94.72
149.43
156.25
130.30
144.43
169.58
108.93
197.33
210.27
JUL
492.49
168.99
274.04
366.69
490.02
217.04
193.94
134.88
197.33
188.12
355.05
234.93
204.82
196.32
175.63
104.42
199.66
137.34
191.03
155.60
240.00
229.84
235.41
202.62
247.09
200.43
257.19
279.17
AUG
SEP
388.20
200.71
273.47
350.38
411.22
208.98
132.36
160.38
222.99
195.11
351.57
220.82
256.32
212.63
195.75
235.00
173.06
182.38
201.42
195.17
268.28
261.05
277.71
240.62
318.35
251.97
280.89
282.57
397.40
228.02
272.45
336.66
432.03
175.99
213.27
69.06
186.50
221.84
358.41
230.54
224.52
155.93
186.07
115.33
97.57
96.64
105.15
71.66
152.54
148.40
168.36
191.13
254.46
111.06
221.67
178.27
OCT
NOV
DEC
311.16 147.53
141.44 27.53
203.27 35.04
275.51 136.16
322.19 99.25
115.48 9.43
171.74 29.44
11.14 0.08
101.24 5.64
121.04 7.01
229.74 61.85
84.79 3.79
88.30 9.84
68.20 1.10
56.45 0.80
29.10 7.42
15.62 0.68
7.17 0.07
9.74 0.32
9.41 0.04
48.28 2.17
30.37 2.81
55.19 0.90
44.47 0.38
61.99 2.72
17.28 0.11
80.82 6.14
38.02 0.67
Tale 1:Showing Data for mean range of rainfall for 28 states for the period of 1978-2007
Source:IITA,Ibadan,2010.
2.1 THE USE OF SURFER SOFTWARE IN ANALYSING RAINFALL PATTERN
Surfer is a grid based contour program.sufer transforms XYZ data to create contour maps,3D
surface maps,3D wire frame maps,shaded relief maps,rainbow colour “image” maps,post
maps,classed post maps,vectormaps,and base maps.It can calculate cross sections,areas,and
volumes.
In analyzing the rainfall pattern for the coastal zones,the surfer software was used to plot the
map of nigeria showing the various climatic zones with the coastal zones having the highest
amount of rainfall.
5
32.13
8.59
10.91
28.99
27.10
0.91
7.89
0.00
0.68
0.64
10.03
0.02
0.03
0.00
0.00
1.56
0.00
0.01
0.05
0.00
0.00
0.02
0.14
0.00
0.07
0.02
2.14
0.53
Fig 2: showing the graphical interface of surfer programme
6
Fig 3: Map showing mean range of rainfall for coastal zones having the highest range of rainfall
Source:researcher’s file ,2011.
7
3.0 CASE STUDY-PROTO TYPE MASS HOUSING AT UNILAG
3.1 Background of Case Study
The various plates used in this write up was gotten from the mass housing quaters of the
University of Lagos Nigeria which is located in the coastal zone of Nigeria climate.The
prototpype mass housing which are sets of prototypes high rise A, B and C and prototypes of
3,and 4 storey buildings of different volumes and shapes built to house the university staffs of
different levels and categories are worthy of study to acertain and establish guidelines for
prototype mass housing designs for the coastal zones of nigeria.
3.2 Implications of design guidelines for Prototype Mass Housing
The guideline for designs in the coastal zones of nigeria has its implication on prototype mass
housing systems in the coastal zones of the country as many factors will be put in place in
ensuring a mass housing pattern that will enhance cross ventilation and maximize the cool
breeze that flows through the North-South Elevations of the buildings and effeciently utilize
the advantages of the coastal zones and try to minimize to the bearest minimun the
disadvantages.Harnessing these specialities in the zone will create a well habitable space that
will promte users functionality and human comfort.Having studied some of the mass housing
quarters in the University of Lagos,Nigeria to assess the implications of these design to thus
serve as a guidelines for prototype mass housing,the following obseravtions were made;
3.2.1 SITE PLANNING AND LAYOUT:The layout of the buildings were of north-south
with the longer axis facing east-west.This was so done so as to trap in the cool air that blows
from the north so that the occupants of the building could feel the cool breeze that blows at
evening times for body comfort.Also noticed was large spaces between buildings to allow
breeze penetration. This was so planned in a manner to allow the windward side to feel the
much impact of the cool air and aviod thesame prototype building blocking the air or causing
suction on other building.The house form also reduces exposure to solar radiation.
8
Plate 1:showing unilag prototype mass housing of three storey arrange in row form to
give a maximum flow of air and reduces solar radiation by placing the smaller side in
the east and western elevation
Plate 2:showing proto type high rise ‘B’mass housing arranged in staggered form to
maximum flow of air.
9
N
Wind direction flow N
N
N
suction
H1
H2
E
S
H3
H4
W
S
S
S
Fig 4a: showing the row arrangement pattern for maximum air flow
Direction of air flow
air flow
airflow
Fig 4b showing: a staggered arrangement of the high rise buildings in a way to permit
air flow through the buildings.
Plate 2: showing a staggered positioning of the buildings.
10
airflow
airflow
h
d=7xh
d
fig 5:showing the distance between each building that will permit adequate flow of air.
d=7xh
d=7xh
Fig6:showing buildings arranged in a staggered form to permit maximum amount of
airflow around the building.
11
3.2.2 OPENING:
Opening of fenestration on the northern and southern elevation were large enough to admit
large amount of air flow and provide enough room for cross ventilation.The western and
eastern walls for the above prototype has no fenestration at all.This shows that more of
radiation is not needed due to lack of need for thermal storage and the windows should be
large and situated preferably in north and south walls.Permanent ventilation should be
provided.Their position should encourage booding cooling.Sunshading devices must be
exclude the sun through out the year.Rain penetration through windows can also be solved
through horizontal shading device tinted at an angle.
3.2.3 STRUCTURE AND MATERIALS:
Walls and floors should ideally be light and of low thermal capacity.This requirement is
difficult to satisfy for floors but walls can be made of louvred shutters and light weight
materials of minimal storage capacities.Roofs should be light,with a relected surface and
cavity for ventilation.The reflective surface of roofs reduces solar heat gain by the roof.The
finishing of walls and roofs should be light to reflect sloar heat.These finishes should protect
against driving rain.
Plate 3:showing the use of brick facing as finishing materials in the non-opening walls
for thermal control.
12
3.2.4 OUTDOOR SPACES:
Balconies were utilized much in the high rise mass housing buildings studied.This balconies
were provided to enhance a greater effeiency of trapping the cool breeze that flows at evening
time.Also overhangs and horizontal shading device were employed in the windows for
shading against the sun.The windows are recessed with the horizontal shading device
protuding out to completely keep the sun away from the northern and soythern
elevations.This is shown in the plate below.
Plate 4: showing out door spaces used in the balconies
3.2.5 SIZE OF OPENINGS:
The size of the openings should be large with 40-80% of this openings facing the North and
South walls.This was the case in the prototype mass housing studied in unilag.This is to allow
the gentle penetration of the south west trade wind in the windward direction so that the
occupants can feel the cool breeze in that blows in the evening time.The eastern and the
western walls should have about 20% of openings and the openings should preferably be of a
medium size to permit minimum amount of sunlight and should be shadded appropriately
with shading device to shade away the sunlight.
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Plate 5:The proto type mass housing above have this characteristics with the eastern
walls have smaller windows and the northern and southern walls having more of the
larger windows.
3.2.6 PROTECTION OF OPENINGS:
protection from rain and direct sunlight can be achieved in a way through the use of shading
device and mostly through the use of trees planted at appropriate distances say 30m from the
building. If a tree is planted say some distances from the window of the massed buildings, it
will hinder an even spread of air through the rooms since the speed of the incoming air will
be retarded down by parts of the tree or even more still those molecules of air that escape
through the pores between the branches and the tree will of course not be at even speed when
entering the house and this will give an uneven air movement throughout the room.
The speed of air above the tree is likely to be of a greater velocity followed by the speed of
air beneath it and the air that flows in a direction that is directly proportional to the trees parts
is more likely to be retarded. This principle is likely employed to cool than the wind velocity
of stormy rains by planting trees of growth height parallel to that of the windows so as to
serve as wind breaker and retarder hence creating an atmosphere of lesser wind effects.
Similarly, the amalgamation of trees and hedges can be used to direct air flow and wind since
the soft landscape will allow the escape of air molecules while the hard landscaping elements
may reflect air flow and reverse its direction.
14
Another elements note of mention here is the window type. Normally Louvered windows is
best for mass housing since it gives room for about to 95%-98% air flow in and out while
about 2% is reflected by the edges of the louvers. Hence as guideline for designs of mass
housing settlement that requires the best in terms of cross ventilation; louvered window will
perform best and can also act as a shading device when tinted at an angle though not to a
greater degree of performance in terms of shading. Also louver can be used to maximize and
minimize appropriate the level of air flow through the openings by tinting the angle of
opening.
More also openings can be protected by using the appropriate shading device. This can both
act as shading against the sun and act as a protective cover against the driving wind. Also the
nature and position of sun shading is paramount consideration when determining the choice
of sun shading device. Recessing window inward can create greater effects in terms of
shading the openings away from the sun and also from the driving rain.
Plate 6:showing trees used as shading device against the sun and to also reduce the effects of
driving rain.
15
airflow
Fig 7: showing the air flow and speed of rainfall retarded by trees planted in growth height parallel
to the window height level
16
4.0 CONCLUSION
In designing for the coastal zones of nigeria with particular reference to prototype mass
housing,the designer should give adequate considerations to the fore going guidelines to
create designs that are environmentally friendly,green in nature and facilitate human
comfortability and climatically adaptive.
17
References
1. Evans, M. (1980). Housing, Climate and Comfort. The Architectural Press, London.
2. Garba, Shaibu Bala & Salisu, Abubakar Sadiq (1995). Land Management Strategies
For Effective Urban Mass Housing In Nigeria. A paper presented at the Nigerian
Institute of Quantity Surveyours Conference, Kaduna
3. Ogunsote, O.O. (1987). "Climatic Zones for Architectural Design In Nigeria: A
Compendium of Existing Definitions and A Proposal for Their Systematic
Delineation". A Doctoral Seminar paper Presented to the Department of Architecture,
Ahmadu Bello University, Zaria.
4. Olgyay, V. (1963). Design With Climate - Bioclimatic Approach To Architectural
Regionalism.Princeton University Press, Princeton, New Jersey.
5. Martin Clark & BA GradDip T.P (1993) Designing for Climate.
18