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BEAM P
LUS
I
NTERIORS
C
OMMERCIAL
, R
ETAIL
A
ND
I
NSTITUTIONAL
A
PPENDICES
9.1 A
SSESSMENT
F
RAMEWORK OF
E
NERGY
P
ERFORMANCE
Copyright © BEAM Society Limited. All rights reserved. Page 127
system:
“The air-conditioning systems, zoning and equipment types of the
base-case should be identical to the designed-case and the system
and equipment of the reference space should exactly meet the
relevant requirements in Section 6 of the BEC.”
Baseline Envelope Design
For the purpose of the assessment of this credit, in the case of
difficulty in extracting the construction details of external walls, roofs
and windows of the assessed space, the baseline building envelope
should be modelled with the dimension of external walls, roofs and
windows measured on site and the default construction characteristics
as given below.
D
EFAULT CONSTRUCTION CHARACTERISTICS FOR THE BUILDING ENVELOPE
External
Thickness
Material
k
density
Cp
alpha
walls
(m)
(W/mK)
(kg/m³)
(J/kgK)
(-)
Layer 1
0.005
Mosaic Tiles
1.5
2500
840
0.58
Layer 2
0.01
Cement/Sand Plastering
0.72
1860
840
Layer 3
0.1
Heavy Concrete
2.16
2400
840
Layer 4
0.01
Gypsum Plastering
0.38
1120
840
0.65
Roofs
Layer 1
0.025
Concrete Tiles
1.1
2100
920
0.65
Layer 2
0.02
Asphalt
1.15
2350
1200
Layer 3
0.05
Cement/Sand Screed
0.72
1860
840
Layer 4
0.05
Expanded Polystyrene
0.034
25
1380
Layer 5
0.15
Heavy Concrete
2.16
2400
840
Layer 6
0.01
Gypsum Plastering
0.38
1120
840
0.65
Windows
Layer 1
0.006
Tinted Glass
1.05
2500
840
0.65
SC = 0.65
Window to wall area ratio
As measured on site
Adjacent spaces not assessed but air conditioned
Assume no heat transfer
Adjacent spaces not assessed and not air conditioned
Assume having the same construction characteristics as
external wall
Symbols:
k
Thermal conductivity
de ns ity
Material Density
Cp
Specific Heat Capacity
alpha
Solar absorptivity of exposed surface
SC
Shading coefficient of glazing