Required Roof Insualtion

However there is an exception.

Required roof insualtion.

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

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. Framed wall insulation must meet or exceed r 13. Pa302 1 ceilings with attic spaces n1102 2 1 r402 2 1. These energy code r value requirements change from state to state and even city to city.

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. Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance. Insulation tight to the roof deck i e. Possible locations for insulation within the roof assembly as addressed by ibc include.

Install nailbase for cladding. Insulation entirely above the roof deck directly below the roof deck or both above and below the roof deck. Residential requirements for insulation are divided by the location in the home. Minimum insulation r value requirements non residential above roof deck.

Install roofing underlayment flashing and cladding as per best practices. Nailbase must be vented in high snow load areas. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities. Add insulation to attic.

For block walls interior insulation must meet or exceed r 7 8 and exterior insulation must be r 6. 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. See the department of energy s doe ranges for recommended levels of insulation below. Insulation on the floor of the attic figure 1.

Minimum insulation r value requirements by state. 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.