Z E M C H 2 0 1 2 I n t e r n a t i o n a l C o n f e r e n c e
42
Table 2: Envelope physical characteristics
Project
U value
wall
[W/m
2
.K]
U value
roof
[W/m².K]
U value
ground
[W/m².K]
Solar energy
transmittance
(g)
Compactness
Écoterra
0.16
0.16
0.16
0.53
0.46
Energy Flex
House
0.08
0.09
0.08
0.47
0.41
Leaf House
0.15
0.25
0.15
0.61
0.52
LIMA
0.19
0.17
0.19
0.42
1.07
Plus energy
Houses Weiz
0.09
0.11
0.09
0.55
0.47
Plus Energy
Settlement
Freiburg
0.12
0.12
0.16
0.55
0.56
Riehen
0.13
0.11
0.13
0.52
0.59
Riverdale
0.10
0.06
0.10
0.55
0.74
Lighthouse
0.11
0.11
0.12
0.55
0.87
With respect of windows, U-value varies between 0.70W/m
2
K and 1.35W/m
2
K, which
suggests low values that are very close to Passive House standard. An interesting
feature regarding U-value of windows is that the projects with best net zero-energy
performance (i.e.
Plus Energy Settlement
,
Plus Energy Houses
,
Riehen
and
Lighthouse
)
are characterised by lower U-value of windows compared with the rest of the buildings.
Figure 3: U-values of opaque envelope of the case studies
