Traditional Cold Roof vs Warm Roof Construction
Since April 2006 an existing flat roof has been required to comply with rigorous U Value targets, based on the event that you're refurbishing more than 50% of your roof. Using a warm roof system is often the most efficient way to achieve the results required.
All new-build flat roofs require a warm roof construction
to comply with Part L. The traditional cold roof
construction is not recommended in
Scotland
and is unlikely to fully
comply with Part L "Robust Details".
Composite Sarnadeck warm roof is made from a rigid
insulation board/plywood composite with integral
foil backing that is placed above the roof joists
and onto which the Sarnafil or single ply membrane is laid.
There is
a clear space between the ceiling and the roof
deck. The air remains warm and the foil vapour
control layer protects against condensation. The
system insulates whilst removing the requirement
for ventilating the roof space. This is particularly
important for a flat roof over a kitchen, bathroom
or utility area.
Compare this with the traditional method used
in flat roofing where the insulation material
is placed between the rafters above the ceiling.
Without proper ventilation the warm air condenses
and can lead to rotting timbers and, eventually,
collapse of the roof deck.
The warm roof system is significantly more efficient as a method of insulation compared to the traditional cold roof construction. County Flat Roofing now fit 120 mm thick Kingspan TR26 or 27 as standard when refurbishing an existing flat roof and by doing this we avoid any risk of creating a condensation problem and achieve a 0.18 U Value or better.
To find out more call us today Freephone 0800 09 88 271 for a no obligation free survey, advice and quotation or click here to contact us Nationwide Coverage.
As
part of the Kyoto
Agreement, the
UK
Government
agreed to reduce emissions of ‘greenhouse gases’
in an attempt to reduce the speed of climate change.
The UK has committed to reducing
emissions by 4.3%, third only to Japan
8.5% and
Germany
7.4%. In a large proportion of emissions
are carbon dioxide and a large proportion of
these are down to the thermal inefficiency of
buildings. Government legislation to reduce heat
loss from buildings is already here.
The requirements of Building Regulations Approved
Document Part L (Part J in
) require that each part
of the building has to adhere to a new higher
thermal efficiency. This measure of heat leakage
is commonly known as the U-value. Many will be
familiar with the current Part L in
England
and
Wales
that
requires windows to meet a U-value of 2.0/m² °C.
In
Scotland
,
Part J, a U-value of 1.8/m² °C has to be met.
For flat roofs the U-value must meet 0.25/m² °C. |
