If an existing cold roof is to be refurbished consideration should be given to converting the design to a warm roof or incorporating new insulation into the roofing system to improve thermal performance.
Warm roof designing.
Warm roofs have significant benefits over cold roofs because.
When the roof deck has served its purpose as a loading or storage platform any necessary local repairs can be made to the vcl before the rest of the roof.
A cold roof is roof in which the thermal insulation layer is located between the ceiling joists meaning that everything above the insulation such as the rafters and any roof space will be colder than the living space below it.
Warm roof inverted roof.
On flat roofs a warm roof is one in which the insulation layer is laid on top of roof structure.
Warm roof designing buildings wiki share your construction industry knowledge.
The membrane is then attached to the insulation.
However a warm roof must meet the requirements of the following new zealand building code clauses.
Energy efficiency is improved heating and ventilation costs are reduced.
The key is to keep the roof deck the principle condensing surface in roof assemblies sufficiently warm throughout the year.
It is usually the most acceptable type of construction for domestic possessions and belongings as it avoids the need for aeration of the roof construction.
Cold roof designing buildings wiki share your construction industry knowledge.
This results in the structural deck and its supports being at a temperature closer to that of the building s interior.
Hot tar and gravel also known as the built up roof bur this type of flat roof features three or more layers of waterproof material mixed in an alternating fashion with hot tar and a layer of smooth stone like gravel.
However if the latter is the case thermal calculations will be required in order to analyse the likelihood of condensation risk.
In case of warm roofs they have an insulation above the roof deck in this way it keeps the deck warm.
As we ve seen though hybrid roofs are as likely if not more likely to occur because of on site issues without the input of designers.
Nowhere does it support the design and construction of hybrid roofs.
This is as opposed to a cold roof in which the insulation is below or within the roof.
There are no specific new zealand standards for.