Required Roof Insualtion

Existing 3 4 inches of insulation.

Required roof insualtion.

Possible locations for insulation within the roof assembly as addressed by ibc include. Insulation entirely above the roof deck directly below the roof deck or both above and below the roof deck. Insulation tight to the roof deck i e. Browse product options or contact your local insulfoam rep to help you quickly pick the best products to simplify your building envelope needs and fit your project budget all with one supplier.

The 2015 irc requires r 49 insulation for ceilings with attic spaces. 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. Iecc 2015 requirements by climate zone 3. Minimum insulation r value requirements by state.

R 38 shall be deemed to satisfy the requirement for r 49 wherever the full height of uncompressed r 38 insulation extends over the wall top plate at the eaves. 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. Install roofing underlayment flashing and cladding as per best practices. However there is an exception.

Recommended insulation levels for retrofitting existing wood framed buildings. For block walls interior insulation must meet or exceed r 7 8 and exterior insulation must be r 6. Residential requirements for insulation are divided by the location in the home. Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance.

Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities. Framed wall insulation must meet or exceed r 13. Add insulation to attic. Nailbase must be vented in high snow load areas.

Building and energy codes almost always specify a required minimum r value for exterior walls and roof assemblies with above deck insulation so the minimum required r value in your local jurisdiction is something that you need to take into account when planning a building project. Minimum insulation r value requirements non residential above roof deck. Insulation on the floor of the attic figure 1. See the department of energy s doe ranges for recommended levels of insulation below.

Install nailbase for cladding. Pa302 1 ceilings with attic spaces n1102 2 1 r402 2 1.