There are two forms of warm deck roof.
Warm deck roof built up.
In principle this keeps the structural deck usually trapezoidal steel or timber at more or less the same temperature as the inside of the building.
Inverted warm deck roof.
In terms of the thermal design of a flat roof what are the options and the best practices of flat roof build ups.
The sandwich warm deck roof is the most common type of flat roof.
In the case of a flat roof insulation is usually either a rigid board above the deck or a mineral glass wool quilt immediately.
A warm flat roof or a built up roof bur is one where all the insulation is above the joists deck making them part of the warm fabric of the building.
Cold flat roofs are typically avoided as you d need to install ventilation which can prove problematic for many reasons relating to.
The vapour control layer is above the decking but below the insulation.
The recognised flat roof build ups for best design practices are.
Warm cold and inverted.
In a warm roof construction the principal thermal insulation layer is located above the structural decking resulting in the structural deck and support structure being at a temperature close to that of the interior of the building.
In a warm roof construction the sarnafil membrane and sarnatherm thermal insulation is installed above the structural decking.
A warm roof deck is the most common and most preferred type of flat roof build up in the uk.
The insulation can be adhered mechanically fixed or loose laid.
There are three recognised designs of flat roof construction.
The insulation is placed below the waterproof covering and is either mechanically fixed or bitumen bonded on to the top of the deck.
Types of warm deck roof.