Insulating Existing Flat Roofs

The target should be to achieve a u value of 0 25w m2k or better.

Insulating existing flat roofs.

To produce a hot roof rigid insulation is fitted outside above the weatherproofing. You will be unable to pass your building or extension through required. There are several different methods for insulating roofs and walls alike but with a flat roof you have to worry about water getting in. Here we share the most common mistakes people make when installing flat roofing insulation.

This is then covered with a further weatherproofing layer. 1 the first method is to use rigid insulation. Composite insulation reduces the need for a cover board when applying different membrane roof coverings. Composite insulation works in flat and low sloped roofs with a variety of roof coverings.

The existing ceiling is sound but provides no insulation. The typical u value of an existing uninsulated flat roof is 1 5w m2k. To insulate an existing dormer we outline three of the more common methods below. There are many different types and installation methods out there along with a lot misinformation about which products offer the greatest energy savings.

There is only a small gap between this ceiling and a concrete roof cold roof felt covered. Roofing insulation is one of the most important and misunderstood building components. Alternatively existing insulation material may be reused when a new roof is installed if it s still in good enough condition. The chances of water seepage with a slanted roof are less simply because water is designed to run off and does not.

Cold roof a very bad idea. Retrofitting flat roof insulation is a difficult task and often a messy one that involves pulling up the waterproof layer that finishes off the deck so as to put flat roof insulation in underneath. This method requires the use of 150mm thick insulation between the rafters and a 50mm air gap to prevent cold bridging occurring. To achieve this add 100 to 160mm of insulation above the structural deck dependant upon insulant conductivity.

I ve built a timber frame to support a new plasterboard ceiling below the existing one. Insulation material is placed on top of the roof. Insulating a flat roof is a task that must be done during construction. Cold roof systems are highly inadvisable as insulation from the inside will inevitably lead to the formation of condensation.

Insulating a flat roof presents a challenge even for experienced roofers and home builders.