From there the flat roof system you choose will determine the materials you apply.
Epdm warm flat roof construction.
This option avoids the requirement to ventilate the roof.
For that reason cold flat roof construction needs to keep in mind the need for unblocked airflow.
Flat roof construction flat roof construction diagram warm roof.
Above is a typical construction of a warm flat roof.
It consists of six basic elements.
Less thermally efficient than a warm roof construction cold roof construction remains the most common form of construction for existing flat roofs.
Thermal insulation which retains heat within the building rather than allowing it to escape through the roof.
A 50mm air gap must be left.
A note to consider before construction.
The insulation material is placed immediately above the ceiling between the rafters.
The benefits it provides and its cost effectiveness over a long term period have seen it become the flat roofing system of choice for many property owners.
Hot tar and gravel.
The 3 most common materials used for flat roof construction.
A vapour control layer must be used below the insulation.
Epdm rubber roofing has firmly established itself as one of the most popular options for flat roofing of all sizes.
If insulation is installed below the flat roof deck this is called a cold roof.
There are several methods and materials for the design of the exterior surface of a warm or cold flat roof.
A waterproof layer which resists water.
Warm deck flat roofs can be constructed on most modern construction material types such as concrete timber and timber based sheets.
This type of roof construction has an insulation layer above the rafters and another layer immediately below its weather proof epdm membrane.
Consider geography budget and use for the roof to determine the best option.
A vapour barrier to prevent moisture.
Warm deck roof construction repair and replacement with an epdm rubber roofing membrane most new flat roof extensions are constructed using the warm roof method.
Continuously changing building regulations mean that the way your epdm flat roof is insulated insulation may need to be changed and your roof turned into a warm roof rather than the typical cold roof.
This approach uses insulation with no air gap either immediately above or below the roof deck.
A cold deck is constructed as follows.
Epdm rubber warm roof being installed over old decking using a new vapour barrier and thermally broken fixings.
To use epdm for a warm deck flat roof construction solid closed cell roof insulation such as kingspan or celotex should be placed on top of the roof deck rather than in between the rafters.