U values by building component.
Pitched roof u value requirement.
External doors windows rooflights curtain walling.
U value requirement roof 0 13 w m k.
U value requirement opaque doors 1 0 w m k.
The new maximum u values are.
If you have any additional enquiries then feel free to drop the celotex technical centre a line on technical celotex co uk.
Pitched roof with insulation between ceiling joists or between rafters determine the thickness of the insulation layer required to achieve a u value of 0 21 w m2k if insulation is between the joists and 0 26 w m2k if insulation is between the rafters.
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 u value requirments for building elements are outlined in part l.
Typically the u value requirement of a pitched roof is 0 18 w m2k which you could achieve with your 150mm between the rafters and another 12mm fixed under the rafters.
U value requirements the u value of a building element i e walls floors or roofs is a measure of the thermal efficiency or heat loss through that element the lower the u value the better the thermeal efficiency of the element.
Note the distinction between the domestic and non domestic columns.
U value requirement floor 0 13 w m k.
The below drawing shows the u value requirements set out for new properties in the building regulations for each element walls floors and roofs.
Achieving a u value of 0 20w m meaning your roof will be better insulated than your walls will need 120mm thickness of rigid foam or 200mm of mineral wool or natural insulation.
We don t count the pitched roof as part of the house as we will insulate the.
Ground floor no underfloor heating 0 45w m k.
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.
Of the building regulations 2007.
U value requirement party walls 0 0 w m k.
Ground floor underfloor heating 0 15w m k.
Highlighted in violet is the first time the u value requirement for a component was strengthened.
Element u value w m2k walls 0 30 floors 0 22 flat roof or roof with integral insulation 0 20 pitched roof insulation at ceiling level 0 16 pitched roof insulation at between rafters 0 20 windows roof windows and roof lights 1 80 doors with more than 50 of the internal surface area glazed 2 20 other doors 3 00.
The tables below show the suggested u values in england wales and scotland.
U value requirement windows whole window u value 1 4 w m k.
U value requirement external walls 0 18 w m k.
Cold roof ceiling level 0 16w m k.
External walls cavity 0 55w m k external walls other not cavity 0 35w m k.
