Flat Roof Dormer Insulation

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.

Flat roof dormer insulation.

The traditional cold deck flat roof system is to install the insulation between and under the joists with ventilation below the timber deck. The photos suggest 25mm of mineral fibre on the underside of the roof. Tlx silver can be used to reduce the thickness of additional insulation required between the joists to help ensure a ventilated gap is maintained between the insulation and the deck. They lose loads of heat and are prone to leaking causing the materials to deteriorate.

Now to the actual question how can you insulate a dormer roof. Tlx silver is a vapour barrier and this structure gives no risk of surface or interstitial condensation. However after taking some photos on the flat roof it is apparent there is already some kind of insulation present. 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.

To produce a hot roof rigid insulation is fitted outside above the weatherproofing. Given below are 3 of the most popular methods by which you can insulate your dormer roof and the best way to tackle this task to achieve the desired results. Unfortunately too many dwellings suffer from this problem. We have a wide range of roof insulation products including flat roof insulation tapered insulation and pitched roof loft insulation.

Cold roof a very bad idea. The rigid insulation method requires the utilisation of 150mm thick insulation in between the rafters along with a 50mm air gap in order to avert cold bridging. With a flat roof this issue does not arise but the u value constraint and the amount of insulation needed is just the same. We also have insulation boards suitable for more specialist roof applications for example inverted roof insulation and balcony insulation.

Cold roof systems are highly inadvisable as insulation from the inside will inevitably lead to the formation of condensation. When using the rigid form of insulation it is possible to place counter battens underneath the battens used for the tiles or slates.