R o o f i n g S y s t e m S u s t a i n a b i l i t y
607
One other point is given by the credit EQ3.1
“Construction IAQ Management Plan:
during construction”
(1 point).
Changing the material of the insulation layers, currently in wood fiber, with a rapidly
renewable material, it is possible to further increase the contribution of the roofing
system achieving the credit MR6
“Rapidly Renewable Materials”
(1 point). In this way the
total score goes to 31 points. In the MUSE project, under LEED certification, cork
insulation layers were used both for roof and walls.
Draft of LEED v.4 (2011, July) application.
In the same way, we have verified the point
contribution of the roofing system according to the LEED v.4 requirements.
It can contribute in achieving a total maximum score of
31 points
:
o
Energy & Atmosphere - EA
(18 points)
o
Materials & Resources - MR
(9 points)
o
Indoor Environmental Quality - EQ
(4 points).
In
EA section
, the roof, thanks to its energy performance, combined with other building
systems and HVAC components can contribute to reach as maximum 18 points
(performance improvement of 46%).
In
MR section
, it is possible to obtain 7 points choosing materials properly and other 2
points can be achieved planning the management of the construction site.
For what concerns the construction site management, the sub-contractor installing the
roof can contribute to the MR2 “
Construction and Demolition Debris Management”
(2
points)
.
The MR credits possible thanks to the roof contribution, following the LCA compliance
path, are:
o
MR1 “
Environmentally Preferable Structure and Enclosure
” (2 points),
o
MR3 “
Non-structural Materials Transparency”
(2 points),
o
MR4 “
Environmentally preferable non-structural products and materials –
prescriptive attributes
” (1 point)
o
MR5
“Responsible Sourcing of Raw Materials”
(1 point)
,
o
MR6 “
Avoidance of chemicals of concern in building materials
” (1 point).
For structural materials (glulam and plywood board), the credit MR1 requires to
demonstrate advantages coming from the chosen design option and to use products with
a documented good life cycle for the construction.
Considering the case study, the use of glulam is the best choice since its low
environmental impact respect to other materials (steel structure or concrete structure);
nevertheless, just the use of low environmental impact products documented by
manufacturer could meet the credit requirements.
For non-structural materials (insulation, brakes and barriers, titanium-zinc sheet, etc.) in
order to meet the MR3 requests it is necessary to use building products with EPDs. For
the case study we have verified the presence on the market of alternative and equivalent
EPD certified materials. Moreover, it is important to underline that these materials shall
be able to satisfy also the requirements of the credit EQ2
“Low-emitting Interiors”
.
For obtaining the credit MR4, the same materials shall have attributes that can
guarantee a better environmental, economic and social performance, such as: materials
with recycled content, bio-based materials, products that support local economy.
The roofing system can also run in achieving credit MR5 demonstrating raw materials
come from responsible sourcing. Examples can be: timber and wood fiber insulation in
FSC certified wood, alloy sheet components extracted from responsible mines, or
gypsum of plasterboard coming from regulated quarries.
