In building construction, roof pitch is a numerical measure of the steepness of a roof. There are typically two different ways to insulate a roof- a warm roof and a cold roof.
Warm pitched roof
A warm roof building will make the entire structure of the building warm in an attempt to avoid any cold bridging. It has s insulation layer above the rafters, and immediately below its weatherproof membrane. A warm roof construction has many benefits over a traditional ‘cold roof’, essentially it is a ‘breathable roof construction’, which allows moisture to escape which in turn prevents damp and any associated decay problems. A warm roof construction allows heat to be conserved within a property – without the need for a ventilation system.
A warm roof is recognized as being the most suited form of roofing to the UK climate, providing both a cost and thermal efficient solution. Thermapitch TP10 is a high performance, fibre free, rigid thermoset insulation used to insulate warm roof spaces in ventilated or unventilated pitched roofs, under tiles or slates.
Cold pitched roof
A cold pitched roof is where the insulation is placed either ‘between’ or ‘between and under’ the rafters or at ceiling joist level. This type of insulation system can be ventilated or not ventilated. However, if the roof is not ventilated then it will require a breathable membrane between the insulation and structure. If you live in an old building you may find that your roofing underlay is sarking felt, if so, you will need to allow for a 50 mm area of ventilation between the insulation and the top of the rafters.