How To Insulate A Flat Roof Extension

Trying to insulate roof in 1970s extension to an old bungalow.

How to insulate a flat roof extension.

To produce a hot roof rigid insulation is fitted outside above the weatherproofing. Hi i have a flat roof extension built in the 1970s. The extension is for a quite small kitchen and bathroom very cold in winter. They lose loads of heat and are prone to leaking causing the materials to deteriorate.

Many properties use this option as there are no additional costs for scaffolding or organising how to gain safe access to the roof exterior. As a refurb project i m resigned to not being to be able to meet best practise for new builds. This is then covered with a further weatherproofing layer. While insulation for a flat roof is expensive and can account for as much as 25 of the total installation cost there are a number of important benefits to having it in place.

Warm deck flat roof insulation is now the standard way to insulate a flat roof click to enlarge flat roofs for example on extensions bathrooms and dormer windows are not the best of ideas. Achieving a u value of 0 20w m meaning your roof will be better insulated than your walls will need 120mm thickness of rigid foam or 200mm of mineral wool or natural insulation. I have been asked if the flat roof of my one storey extension could be used for access when they insulate the outside of the party wall with external wall insulation. Cold roof a very bad idea.

How much gap should i leave in between the insulation and the top of the roof i m thinking of getting some kingspan to insulate. Reduce extreme temperature fluctuations inside your home. The insulation material is placed between the supporting joists leaving a gap of 50 60mm between the roof and insulation. Insulating a flat roof how much gap should i leave in between insulation and top of the roof.

Although cold roof systems were used extensively in the past they are now considered out of date and are highly inadvisable. With a flat roof this issue does not arise but the u value constraint and the amount of insulation needed is just the same. I ve recently had two. Wondered if anyone else has come across a similar challenge what you did please.