Minimum Insulation In Roof

Hitting amazing levels of 0 13w m will need 300mm of mineral wool or 180mm of rigid foam.

Minimum insulation in roof.

Less than the prescriptive r value at per foot slope as long as the system r value meets or exceeds that. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities. See the department of energy s doe ranges for recommended levels of insulation below. Existing 3 4 inches of insulation.

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. Recommended insulation levels for retrofitting existing wood framed buildings. Recognized by the iecc. Zone 6 requires an r 30 minimum which is 5 2 thick.

Adhered bituminous membrane minimum requirements adhered single ply membrane minimum requirements see notes below for required perimeter and corner enhancements2 3 2 3see notes below for required perimeter and corner enhancements insulation type thickness 4 x 4 4 x 8 insulation type thickness 4 x 4 4 x 8. 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 4 r 25 5 r 25 state only mt montana 2012 iecc 6 r 30. Add insulation to attic. Minimum insulation r value requirements by state.