GreenTips

The choice of roofing material can have a significant effect on the solar gains of a building. Light coloured roof finishes reflect radiant heat while dark colours absorb radiant heat. Heavy weight roofing materials such as concrete will heat slowly and delay the arrival of solar energy to the interior.

When selecting a roofing material give consideration to the durability, maintenance requirements and recyclability on demolition. Most metal profiled roofing can be recycled but some metals, such as zinc, will have an inherently longer lifespan and require less or no surface finishes.

Other products such as fibrous cement sheet contain sustainably managed cellulose fibres, but they also contain cement, which is a known significant contributor to man-made greenhouse gas emissions.

Heavyweight tiled roofing accounts for about 25% of a building’s mass above ground. The environmental and economic cost must include the additional structure required to support the roof.

Rainwater run-off pollution will be affected by the choice of roof. Some materials, such as copper and galvanised steel, are thought to be responsible for increasing levels of zinc and copper pollution in our waterways and contamination of stormwater.

Click on the following roofing types for further information:
profiled metal roofing (www.metalroofing.org.nz)
zinc sheeting
copper roofing
slate roofing
concrete roof tiles

Clay tiles

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