Residential Roof Insulation Requirements

Recommended insulation levels for retrofitting existing wood framed buildings.

Residential roof insulation requirements.

The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process. Existing 3 4 inches of insulation. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities. The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.

Insulating a roof is perhaps the easiest of all the energy saving home improvements. It s also within the capability of most diyers although not the most pleasant of tasks. Cavity fibrous or cellulose insulation can be installed at levels up to r 15 in a 2 inch x 4 inch wall and up to r 21 in a 2 inch x 6 inch wall. Insulation climate zone requirements.

Add insulation to attic. Minimum insulation r value requirements by state. Gables to be insulated as exterior walls. State applicable energy ashrae zone minimum r value state.

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. Ak alaska 2012 alaska building energy efficiency standard 7 r 35 8 r 35 9 r 40. The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.

Mineral wool rolls are ubiquitous and cheap meaning a whole roof on a standard home could be insulated to the recommended 270mm with a spend of little more than 200. R values can be higher for foam insulation and other advanced insulation systems. See the department of energy s doe ranges for recommended levels of insulation below. Refer to the requirements for each building envelope area based on your project s climate zone.

Mandatory minimum r 22 attic insulation unvented attics must be air sealed at roof deck eaves gables and penetrations. Determine your climate zone. Alternatively you can search for your zone by county through energy gov s here. Minimum insulation r value requirements non residential above roof deck.