Insulating Hot Cold Flat Roof

Warm roofs offer a superior thermal performance and therefore come with a higher cost.

Insulating hot cold flat roof.

You can expect to pay about 55 100 sq ft. The insulation material is placed between the supporting joists leaving a gap of 50 60mm between the roof and insulation. Basically the term cold roof refers to a traditional roof or vented roof while hot roof refers to a roof that is not ventilated and which has foam insulation attached directly to the roof sheathing. While expensive the best insulation is polyiso rigid foam.

Flat concrete roofs are generally not ventilated since the ceiling internally is generally a plaster and skim coat directly to the underside of the cold concrete. Many properties use this option as there are no additional costs for scaffolding or organising how to gain safe access to the roof exterior. Warm flat roof insulation. This is then covered with a further weatherproofing layer.

This means there is a vapour control layer in the ceiling and cross ventilation at the eaves or the top of the walls. Lots of traditional flat roofs are of the cold roof construction type. We recommend having at least 20 r value worth of material for optimal energy efficiency. Cold roof a very bad idea.

To produce a hot roof rigid insulation is fitted outside above the weatherproofing. No ventilation is required for these types of roofs. On a warm flat roof the layer is installed underneath the insulation to stop moisture interacting with it through rising thermal pressure lower down in the building. With a warm roof the insulation is installed on top of the existing surface rather than in between the rafters.

For cold flat roofs the vapour layer needs to be positioned underneath the insulation layer on top of the room below to create an effective barrier. Cold flat roof insulation. 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. This will enable the airflow to circulate freely.

It is top quality and the most cost effective product for your flat roof. There are three types of insulation solution if you have a flat roof. Warm deck or warm roof refers to a situation where the deck of the roof which is usually made of wood is below the. Cold roof systems are highly inadvisable as insulation from the inside will inevitably lead to the formation of condensation.

For a 1 inch board equivalent of 6 r value. This may help with condensation but causes such a loss of heat that it has been banned in scotland.