Pitched roof sloping ceilings.
Pitched roof u value requirement.
U values by building component.
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.
Hitting amazing levels of 0 13w m will need 300mm of mineral wool or 180mm of rigid foam.
Ground floor underfloor heating 0 15w m k.
U value requirement semi glazed doors 1 2 w m k.
U value requirement roof 0 13 w m k.
The u value requirments for building elements are outlined in part l.
U value requirement opaque doors 1 0 w 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.
U value requirement party walls 0 0 w m k.
Ground floor no underfloor heating 0 45w m k.
We don t count the pitched roof as part of the house as we will insulate the.
Cold roof ceiling level 0 16w m k.
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 tables below show the suggested u values in england wales and scotland.
Highlighted in violet is the first time the u value requirement for a component was strengthened.
The new maximum u values are.
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.
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.
External doors windows rooflights curtain walling.
Note the distinction between the domestic and non domestic columns.
U value requirement windows whole window u value 1 4 w m k.
External walls cavity 0 55w m k external walls other not cavity 0 35w m k.
If you have any additional enquiries then feel free to drop the celotex technical centre a line on technical celotex co uk.
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.
U value requirement external walls 0 18 w m k.
U value requirement floor 0 13 w m k.
