Warm deck this is where the insulation is placed on top of the rafters joists and the roof covering is then placed over the insulation.
Roof insulation uk regulations.
No ventilation is required for these types of roofs.
Cold deck this is where the insulation is placed between the joists rafters or in between the ceiling joists in the case of a pitch roof.
A qualified roofing contractor will be able to advise on this but here are some of the main guidelines.
Building regulations standards set the levels of thermal insulation required when carrying out building work either for new build or refurbishment projects.
The required u value will depend on the location of the project england scotland or wales type of building domestic or non domestic and the application floor wall or roof.
Currently uk building regulations stipulate that a minimum depth of 270mm is required to adequately protect your home and keep it properly insulated.
Building regulations does not determine which material must be used but it stipulates what qualities it must posses.
Care should be taken not to block any ventilation at the edges eaves.
These are expressed as a u value which needs to be achieved.
Insulation and thermal elements.
Nhbc regulation 2011 insulation and control of condensation.
If you are installing loft insulation as part of a roof renovation project where more than 25 per cent of the roof is being renewed then the level of insulation should meet the standards required by building regulations approved documents.
There must be a slope of 1 80 part h of the building regulations regarding drainage state that water should drain to one or two edges waterproofing should extend up the adjacent walls at least.
This is just under a third of a metre which may seem like quite a lot to you.
The actual regulations require that loft insulation should be at least 270 mm thick and must have good thermal properties.
Walls are defined by regulation 2 3 of the building regulations 2010 as being thermal elements.
Building regulations for insulating a roof.
7 2 d11 a ventilation of main roof spaces pitched roofs with insulation at ceiling level should always be ventilated to the outside air to minimise the risk of ventilation.