Warm Deck Roof Insulation Thickness

Min 125 thickness of insulation board then finish on top.

Warm deck roof insulation thickness.

These often have a deck of plywood with a cellular insulation and metal foil vapour control layer bonded to the underside and a top layer with an overlay factory bonded to it. Cold flat roofs are typically avoided as you d need to install ventilation which can prove problematic for many reasons relating to space labour costs etc. Add to this the firring pieces for slope say 75 max. The vapour control layer is above the decking but below the insulation.

Set the quinn therm qrfr ply insulation boards onto a wide 30mm bead of vapour resistant sealant applied to the upper surface of all the joists and cross noggins. Composite board can be found on both warm and inverted roof applications. Warm deck the type of insulation for this is usually of a rigid type and the thickness will vary depending on the manufacturer s specifications. Cold deck roof a cold deck roof is where the insulation is placed between the joists rafters or in.

Warm deck roof a warm deck roof is where the insulation is placed on top of the rafters joists and the roof covering is then placed over the insulation. A flat roof where the insulation sits below the waterproof membrane and above the structural deck is a warm roof deck. The joist size depends on your span but assuming you are going out say 3m or so your joists would be about 150 deep. Warm flat roofs do not need to be ventilated as the insulation is.

There is a likelihood that this practice could contribute to a condensation risk and therefore it would be strongly recommended to have a condensation risk. Ventilation is required for these roofs. 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. The insulation is immediately below the waterproofing layer.

No ventilation is required for these types of roofs. The waterproof layer is above the insulation and a vapour control layer is placed below the insulation. A warm roof has the insulation above the structural deck which is thus kept warm. The warm deck roof design is the modern method for flat roof construction and is preferred wherever this option is possible.

It is not unusual for designs to keep roof levels to a minimum and there is a trend when designing a warm roof to include some of the insulation below the structural deck as well as above. 18 thickness of deck. Warm deck insulation 1. So called because the insulating layer is located above the roof rafters and between the structural supports a warm deck roof results in a temperature for the roof and loft area that is consistent with the rest of the.

Cold deck this is where the insulation is placed between the joists rafters or in between the ceiling joists in the case of a pitch roof. How to install insulation in a flat roof with timber deck insulated above the joists.