Thermal Building Design
Wall Design and Heat Transfer Analysis
Roof Design
Gypsum
Wallboard
Tar Paper
Spray Applied
Glass Fiber
Polystyrene
Insulation
Plywood
Sheathing
2” x 6” Stud
Asphalt Roof
Shingles
Roof
Component
Heat Transfer
Method
Material
inches
Gypsum
Wallboard
Conduction
Wallboard
Conduction
Inside Film
Gypsum
Board
0.625
Between
Studs
0.12
millimeters
15.875
R-Value
(m2K/W)
0.16
At Studs
0.12
0.09921875
0.09921875
2.30948043
-
11.2
-
-
1.55222222
0.038
Tar
Paper
Spray
Applied
Glass Fiber
Inside Film
Thermal
Conductivity
(W/mK)
Thickness
Polystyrene
Insulation
Plywood
Sheathing
2” x 6”
Stud
Insulation
Conduction
Spray Applied
Glass Fiber
3.5
88.9
0.039
Insulation
Board and
Slab
Conduction
Polystyrene
2
50.8
Stud
Conduction
Spruce
5.5
139.7
Plywood
Conduction
Plywood
0.625
15.875
0.15
0.15
Roofing
Conduction
Asphalt
0.035
0.889
0.078
0.078
Outside Film
Convection
Outside Film
0.03
0.03
R-Value
(m2K/W)
R-Value
(m2K/W)
13.9866992
2.02944097
U-Value
(W/m2K)
U-Value
(W/m2K)
0.0714965
0.49274653
Total
Total
Thickness (in) Thickness (m)
Asphalt
Roof
Shingles
6.785
172.339
0.09
Total U-Value Total U-Value
(W/m2K) (BTU/hr ft2 °F)
0.1136215
0.02000993
Exterior Walls
Gypsum
Wallboard
Spray Applied
Glass Fiber
2” x 6” Stud
Plywood
Sheathing
Vinyl House
Siding
Exterior Walls
Component
Heat Transfer
Method
Material
Thickness
inches
Inside Film
Conduction
Wallboard
Conduction
Inside Film
Gypsum
Board
0.625
Thermal
Conductivity
(W/mK)
Between
Studs
0.12
millimeters
15.875
R-Value
(m2K/W)
0.16
At Studs
0.12
0.09921875
0.09921875
3.62918354
-
-
1.55222222
0.038
Gypsum
Wallboard
Insulation
Conduction
Spray Applied
Glass Fiber
5.5
139.7
0.039
Spray
Applied
Glass Fiber
2” x 6”
Stud
Stud
Conduction
Spruce
5.5
139.7
Plywood
Conduction
Plywood
0.625
15.875
0.15
0.15
Siding
Conduction
Foil Backed
0.035
0.889
0.52
0.52
Outside Film
Convection
Outside Film
0.03
0.03
R-Value
(m2K/W)
R-Value
(m2K/W)
4.54840229
2.47144097
U-Value
(W/m2K)
U-Value
(W/m2K)
0.21985742
0.40462225
Plywood
Sheathing
Total
Total
Thickness (in) Thickness (m)
6.785
Vinyl House
Siding
172.339
0.09
Total U-Value Total U-Value
(W/m2K) (BTU/hr ft2 °F)
0.24757215
0.04360003
Above Ground Basement Walls
Gypsum
Wallboard
Poured
Concrete
Tar Paper
Spray Applied
Glass Fiber
Polystyrene
Insulation
2” x 6” Stud
Plywood
Sheathing
Vinyl House
Siding
Above Ground Basement Wall
Poured
Concrete
Component
Heat Transfer
Method
Material
inches
Gypsum
Wallboard
Inside Film
Conduction
Inside Film
Wallboard
Conduction
Gypsum
Board
Thermal
Conductivity
(W/mK)
Thickness
0.625
millimeters
15.875
0.16
R-Value
(m2K/W)
Between
Studs
At Studs
0.12
0.12
0.09921875
0.09921875
3.62918354
-
-
1.55222222
0.038
Tar
Paper
Insulation
Conduction
Spray Applied
Glass Fiber
5.5
139.7
0.039
Stud
Spray
Applied
Glass
Fiber
2” x 6”
Stud
Polystyrene
Insulation
Plywood
Sheathing
Conduction
Exterior Wall
Poured
Conduction
Concrete
Spruce
5.5
139.7
Sand and
Gravel or
stone
aggregate
8
203.2
2.15
-
Insulation
Board and
Slab
Conduction
Polystyrene
2
50.8
11.2
-
Plywood
Conduction
Plywood
0.625
15.875
0.15
0.15
Siding
Conduction
Foil Backed
0.035
0.889
0.52
0.52
Outside Film
Convection
Outside Film
0.03
0.03
R-Value
(m2K/W)
R-Value
(m2K/W)
17.8984023
2.47144097
U-Value
(W/m2K)
U-Value
(W/m2K)
0.05587091
0.40462225
Total
Total
Thickness (in) Thickness (m)
16.785
Vinyl
House
Siding
0.09
426.339
Total U-Value Total U-Value
(W/m2K) (BTU/hr ft2 °F)
0.10818361
0.01905226
Subterranean Walls
Gypsum
Wallboard
Poured
Concrete
Tar Paper
Spray Applied
Glass Fiber
2” x 6” Stud
Polystyrene
Insulation
Subterranean Wall
Gypsum
Wallboard
Poured
Concrete
Component
Heat Transfer
Method
Material
inches
Inside Film
Conduction
Wallboard
Conduction Gypsum Board
Thermal
Conductivity
(W/mK)
Thickness
millimeters
Inside Film
0.625
15.875
0.16
R-Value
(m2K/W)
Between Studs
At Studs
0.12
0.12
0.09921875
0.09921875
3.62918354
-
-
1.55222222
0.038
Insulation
Conduction
Spray Applied
Glass Fiber
5.5
139.7
0.039
Spray
Applied
Glass Fiber
Tar
Paper
Stud
Conduction
Spruce
5.5
139.7
Exterior Wall
Poured
Concrete
Conduction
Sand and
Gravel or
stone
aggregate
8
203.2
2.15
-
Insulation
Board and
Slab
Conduction
Polystyrene
2
50.8
11.2
-
Outside Film
Convection
Outside Film
0.03
0.03
R-Value
(m2K/W)
R-Value
(m2K/W)
17.2284023
1.80144097
U-Value
(W/m2K)
U-Value
(W/m2K)
0.05804369
0.55511117
Total
Total
Thickness (in) Thickness (m)
2” x 6”
Stud
Polystyrene
Insulation
16.125
409.575
0.09
Total U-Value Total U-Value
(W/m2K) (BTU/hr ft2 °F)
0.13260381
0.02335291
Heat Transfer Analysis – No Space Heating Needed
UExterior
AExterior
Uroof
Aroof
Ubase_below Abase_below Ubase_above Abase_above Uwindow Awindow Ext Awindow_abv base
Udoor
Adoor_Ext Adoor_abv base UATOTAL
BTU/hr ft2 °F
ft2
BTU/hr ft2 °F
ft2
BTU/hr ft2 °F
ft2
BTU/hr ft2 °F
ft2
BTU/hr ft2 °F
ft2
ft2
BTU/hr ft2 °F
ft2
ft2
0.0436
2660
0.02001
1600
0.0233529
540
0.019052
730
0.24
216
24
0.3
20
38.921875
0.081203
0.032876712
0.007519
0.05331764
BTU/hr °F
238.2988
Area Ratio
R-Value
(hr ft2
°F/BTU)
0.911278
22.93576
0.913806
49.97519
42.821216
52.48721
4.166667
3.333333
Heat Transfer Analysis
Heat Transfer for Average High
Month
Average High Average Low
Ambient
Room
Temperature
Heat Transfer
In or Out of
House?
Heat Transfer
Heat Transfer for Average Low
Heat Transfer
Heat
Generation
Typical
Heat Transfer In or
Electric
Out of House?
Heater Heat
Transfer
Heat
Produced
Δq
-
°F
°F
°F
BTU/hr
W
In or Out?
BTU/hr
W
In or Out?
BTU/hr
BTU/hr
January
65
48
68
714.89652
209.5155
out of
4765.977
1396.77
out of
5200
434.0232
February
66
50
68
476.59768
139.677
out of
4289.379
1257.093
out of
5200
910.6209
March
66
52
68
476.59768
139.677
out of
3812.781
1117.416
out of
5200
1387.219
April
68
55
68
0
0
into
3097.885
907.9005
out of
5200
2102.115
May
69
58
68
-238.2988
-69.8385
into
2382.988
698.385
out of
5200
2817.012
June
71
61
68
-714.8965
-209.5155
into
1668.092
488.8695
out of
5200
3531.908
July
76
65
68
-1906.391
-558.708
into
714.8965
209.5155
out of
5200
4485.103
August
78
67
68
-2382.988
-698.385
into
238.2988
69.8385
out of
5200
4961.701
September
77
65
68
-2144.69
-628.5465
into
714.8965
209.5155
out of
5200
4485.103
October
75
60
68
-1668.092
-488.8695
into
1906.391
558.708
out of
5200
3293.609
November
70
54
68
-476.5977
-139.677
into
3336.184
977.7389
out of
5200
1863.816
December
66
49
68
476.59768
139.677
out of
4527.678
1326.931
out of
5200
672.322
Economic Analysis – Net Present Worth
Year #
Future Value Fuel Cost
Present Worth of the Fuel Cost
n
(1+i)(n-1) (i=8.4%)
1/(1+d)n (d=0.75%)
1
30
29.77667494
2
32.52
32.03763338
3
35.25168
34.47026758
4
38.21282112
37.08761296
5
41.42269809
39.90369474
6
44.90220473
42.93360307
7
48.67398993
46.19357393
8
52.76260509
49.70107606
9
57.19466391
53.47490467
10
61.99901568
57.53528205
11
67.206933
61.90396599
12
72.85231537
66.60436639
13
78.97190986
71.66167064
14
85.60555029
77.10297863
15
92.79641652
82.95744797
16
100.5913155
89.25645023
17
109.040986
96.033739
18
118.2004288
103.3256308
19
128.1292649
111.1711998
20
138.8921231
119.612487
TOTAL
NET PRESENT WORTH
1302.74426