Loft Insulation Between Roof Rafters

Its been done before by a right cowboy with only a small or no gap between the insulation and the roofing felt and condensation was forming on the underside of the felt.

Loft insulation between roof rafters.

I m wanting to insulate between the rafters of my loft. Common rafter depths range from 100mm to 200mm. Time to get the insulation finished and get this place warm. An efficient room in a roof in a new build property where over rafter insulation is not desirable.

An alternative way to insulate your loft is to fit the insulation between and over the rafters these are the sloping timbers that make up the roof itself. Its versatility is the key to its popularity whether being used to achieve. The eaves are ventilated do i need to ventilate the ridge. I m moving the insulation out to form a 50mm gap.

If 180mm is to be installed then 100mm board might be introduced between the rafters there has to be a minimum 25mm air gap between the insulation and the underside of the tiles or slates with an 80mm board running across the rafters. This limits the maximum thickness of the insulation between the rafters to between 50mm and 175mm. We would always recommend having a breathable membrane in place between the tiles and the rafters too to allow the roof to breathe. But if you plan to use your loft for storage only then a conventional cold roof option where the mineral wool insulation rolls are placed in between the ceiling joists above the top floor.

So whether it s a new build project or if you re creating a habitable area when renovating an existing loft space the insulation line will need to be within the pitched sloped part of the roof so insulation will need to be installed between the timber rafters to provide protection to the newly created habitable area from external. With a warm roof the usual process is to split the insulation into two layers. Check out our how to video at the link below. When you use solid insulation board to create a warm loft the key thing to remember is ventilation you must keep a 50mm gap between the roof and the rigid insulation board.

Https youtu be w4mkphzmqxw contact us restorat. If the loft is going to be used as living space then the insulation should be placed at rafter level to create a warm roof.