New Flat Roof Insulation Regulations

On new build or replacement pitched roofs the ideal build up would be insulation fitted over and then between the rafters giving a big boost for airtightness image credit.

New flat roof insulation regulations.

If you are replacing more than 25 of the roofing area then you will also need to replace the thermal insulation. This will also be reflected in the energy performance certificate for your property which is a requirement for all buildings. Our guides to building regulations in wales adl1a 2014 building regulations. You carry out structural alterations the performance of the new covering will be.

You are making any structural changes to the roof. You are replacing repairing more than 25 per cent of the roof area in which case the roof thermal insulation would normally have to be improved. If the new roof covering is going to be different than the old one and this will affect the roof in the event of a fire. Wales new dwellings.

You will need approval however if. Ventilation is required for these roofs. Kingspan with a flat roof this issue does not arise but the u value constraint and the amount of insulation needed is just the same. Summary of flat roof building regulations.

A u value of 0 55 w m k is used for cavity insulation and 0 30 w m k for internal or external wall insulation. The actual specification required for a compliant building and necessary building fabric u value targets may vary depending on the actual overall proposed specification and the outcome of the energy. The performance of the new covering will be significantly different to that of the existing covering in the event of a fire. Insulation can be placed between the ceiling joists.

Insulation can also help to limit condensation and contribute to acoustic insulation depending on the type of insulation used. U value of a flat roof to comply with part l of the building regulations 2010 all roofs to rooms except those in unheated buildings should be thermally insulated to a maximum u value of of 0 18 w m k. 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. You should fully consult the regulations and the approved document and if you are in any doubt seek advice before commencing work.

The definition of a thermal element does not include windows doors roof windows or rooflights. The below drawing shows the u value requirements set out for new properties in the building regulations for each element walls floors and roofs.