0 039 12 fiberglass insulation.
Flat roof minimum u value.
Minimum r value state local al alabama 2015 alabama commercial energy code 2 r 25 3 r 25 state local ak alaska 2012 alaska building energy efficiency standard 7 r 35 8 r 35.
Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials.
Walls 0 30 w m2 k.
Roofs 0 20 w m2 k.
Ground floor underfloor heating 0 15w 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.
R value of various materials.
Ground floor no underfloor heating 0 18w m k.
For a very good introductory overview article on r value see r values over at the website of.
A lower u value indicates better insulation properties hence u value requirements usually specify a maximum value.
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.
All new projects must prove themselves to be reasonably energy efficient.
Floor 0 25 w m2 k.
Flat metal roof.
Typical recommendations for exterior walls are r 13 to r 23 while r 30 r 38 and r 49 are common for ceilings and attic spaces.
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.
However in new builds u values are part of the overall goal for energy efficiency.
Depending on where you live and the part of your home you re insulating walls crawlspace attic etc you ll need a different r value.
Insulation for walls including cavity walls solid walls and timber or steel framed walls.
0 05 8 fiberglass insulation.
Insulation for flat roofs pitched roofs and balconies and terraces.
Cold roof ceiling level 0 16w m k.
U value of a flat roof.
You should of course see the manufacturer provided technical data sheet for the r value of specific products.
0 027 wood roof.
0 16 3 fiberglass insulation.
State applicable energy ashrae zone minimum r value state local ms mississippi ashrae 90 1 2010 2 r 20 3 r 20 state local mo missouri 2012 iecc.
The current legal limits under building regulations part l are as follows.
0 26 2 fiberglass insulation.
0 11 4 fiberglass insulation.
Get a u value calculation from our free online u value calculator or our technical department.
0 071 6 fiberglass insulation.
0 90 1 fiberglass insulation.