Required Roof Insualtion

The 2015 irc requires r 49 insulation for ceilings with attic spaces.

Required roof insualtion.

Nailbase must be vented in high snow load areas. Install roofing underlayment flashing and cladding as per best practices. Add insulation to attic. Install nailbase for cladding.

Minimum insulation r value requirements by state. Recommended insulation levels for retrofitting existing wood framed buildings. Ceiling insulation must be much higher at r 30 and a raised floor must be at least r 13. 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.

Continuous insulation zones ashrae 90 1 ashrae 189 1 igcc ibc iecc 2004 2007 2010 2013 2016 2009 2011 2014 2012 2015 2009 2012 2015 0 25 1 15 20 2 15 20 25 3 15 20 25 4 15 20 302535 5 15 20 302535 6 15 20 3035 7 15 20 3540 25 8 20 3540 25 minimum r value non residential above roof deck. Possible locations for insulation within the roof assembly as addressed by ibc include. Iecc 2015 requirements by climate zone 3. Insulation on the floor of the attic figure 1.

Insulation entirely above the roof deck directly below the roof deck or both above and below the roof deck. 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. See the department of energy s doe ranges for recommended levels of insulation below. Residential requirements for insulation are divided by the location in the home.

Existing 3 4 inches of insulation. 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. 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. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities.

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. However there is an exception. Framed wall insulation must meet or exceed r 13. Insulation tight to the roof deck i e.

Pa302 1 ceilings with attic spaces n1102 2 1 r402 2 1. For block walls interior insulation must meet or exceed r 7 8 and exterior insulation must be r 6.