Pipes water tank and loft hatch.
Warm roof insulation depth.
Insulation which prevents any risk of condensation and stops the build up of damp within the roof.
The typical u value of an existing uninsulated flat roof is 1 5w m2k.
To eliminate all condensation risks and making it a true warm roof construction.
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.
Cold flat roofs are typically avoided as you d need to install ventilation which can prove problematic for many reasons relating to space labour costs etc.
Insulating between the joists of your loft will keep your house warmer but make the roof space above colder.
With a warm roof the usual process is to split the insulation into two layers.
Energy efficiency grants are currently available for cold loft roof insulation.
A flat roof where the insulation sits below the waterproof membrane and above the structural deck is a warm roof deck.
Warm roof solutions are generally more.
Warm deck the type of insulation for this is usually of a rigid type and the thickness will vary depending on the manufacturer s specifications.
Flat roof insulation always requires professional insulation and damp roofs require professional assessment before work can be carried out.
Flat roof insulation thickness.
The benefits of a warmer roof 2 3 day installation time.
Our roof conversions can be completed in just 2 3 days.
There is a requirement when refurbishing a roof to have a minimum u value of 0 18 w m k in england and wales but for a complete re roof in wales the minimum u value required is 0 15 w m k.
It should be of the maximum available thickness.
The roof insulation thickness will vary dependent on the required u value.
The below table shows the thickness of insulation required for a typical warm roof construction with insulation fitted above the rafters.
As only a few years ago the recommended depth of insulation was 200mm.
When specifying the insulation for the pitched roof it is important that the thickness of insulation used achieves the required u value.
The chosen insulation laid on top of this should be able to take the weight of anything put above it on the roof without compression or protected from compression by further sheeting.
Our u value calculator is free and simple to use for calculating u values specific to your roof construction design.
Warm flat roofs do not need to be ventilated as the insulation is.
