Minimum Insulation In Roof

Minimum insulation r value requirements non residential above roof deck.

Minimum insulation in roof.

Minimum insulation r value requirements by state. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities. 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.

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. Existing 3 4 inches of insulation. Less than the prescriptive r value at per foot slope as long as the system r value meets or exceeds that. Zone 6 requires an r 30 minimum which is 5 2 thick.

Add insulation to attic. Hitting amazing levels of 0 13w m will need 300mm of mineral wool or 180mm of rigid foam. See the department of energy s doe ranges for recommended levels of insulation below. Recognized by the iecc.