Net ZEB Case Studies - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 457

7.5.4 Materials

Regarding the envelope, the walls are made of concrete; the roof is insulated
using a 10 cm layer of polystyrene with a ventilated BIPV array over the
roof;thesolarshadingsystemsaremadeofwoodenstrips;theeastandwest
gablesareinsulatedwithmineralwoolandwoodencladding.Thepaintused
is organic and the wooden components have not undergone any chemical
treatment. In order to reduce cost, no insulation is used on the main façades
that are shaded by the exterior louver shading systems ( Table 7.19 ) .

Table 7.19 Envelope description of the ENERPOS

Roof BIPV on exterior of roof + 10 cm of polystyrene + 20 cm

concrete
Overall R -value: 3.4 m 2 K/W
Solar factor (the percentage of solar heat that penetrates the
roof to the building's interior): 0.003
East and West: 18 cm concrete + 8 cm mineral wool, or 18 cm
concrete + ventilated air gap + wooden siding
Overall R -value: 1.8 m 2 K/W
Solar factor: 0.02

Walls

North and South: 18 cm concrete + solar shading
Overall R -value: 0.1 m 2 K/W/Solar factor: 0.03
Window-to-wall ratio: 30%
Windows U -value: 1.4 W/m 2 K
Effective solar heat gain coefficient (SHGC) including solar
shading: north, 0.10; south, 0.15
Visible transmittance: 0.4

7.5.5 Ergonomics and Interior Design

A particular effort was made for the indoor design of all spaces, ranging
from the wall colors to the choice of interior furniture. The building team
aimed to prove that a comfortable working space can be designed without
extra costs. The offices' ergonomics were studied to achieve a maximum
level of comfort for occupants: desks are positioned perpendicularly to the
windows, at a 0.5 m distance, to avoid glare and direct solar radiation