90
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design
mag
The selection of a roofing material can have a critical impact
on the temperatures inside a house and the consequent
level of artificial heating and cooling. Research conducted
by the University of Newcastle’s Faculty of Engineering and
Built Environment has established that concrete roof tiles offer
superior thermal performance in hot conditions.
The tests compared a concrete tiled roof to a sheet metal
roof, both without sarking, and took note of the amount of
cooling energy required to maintain a comfortable
temperature in living areas.
The research went further and compared light and dark
coloured roofing in both materials to determine if this had
any bearing on the results.What is clear from the results is
that while a lighter-coloured roof offers a marginal difference
in heat absorption due to reflectivity, the material itself had a
greater bearing and in this regard concrete roof tiles were the
superior performer.
A roof does have a lot to carry: wind loads, weathering and
even fire.As this research demonstrates, a tiled roof can carry
its environmental load as well as whatever else nature can
throw at it.
Thermal efficiency –
keeping a lid on costs
The bottom line
Sources: Sugo, H, Luo, C. & Upadhay,A. Preliminary Assessment of the influence of Roof
Colour and Material on the Thermal Performance of a Simple Structure,The University of
Newcastle, report in confidence, Roofing Tile Association of Australia (2006).
Sugo, H,Thermal Performance of Roofing Materials – Calibration of Roof Testing Apparatus
and Assessment of Six Tile Products With and Without Ventilation,The University of
Newcastle, report in confidence, Roofing Tile Association of Australia (2008).
0
100
200
300
400
500
600
700
800
900
497
567
664
825
Mean Cooling Energy (KJ.m2/Day)
Tile
Corrugated
Steel
Corrugated
Tile
Corrugated
Steel
Corrugated
Light Coloured Products
Dark Coloured Products
0.54
Solar
Absorption
0.54
Solar
Absorption
0.96
Solar
Absorption
0.96
Solar
Absorption
Daily heat energy required comparing
products without insulation
