New Roof Insulation Requirements

Whether you re doing a weekend fix or folding it into a bigger home renovation insulating your roof will pay off for years to come.

New roof insulation requirements.

A minimum of a 30 astm felt should be used as an underlayment. 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 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.

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. The information contained in this document is meant to be used as a quick reference guide for insulation levels across the united states. Minimum insulation r value requirements non residential above roof deck.

With a flat roof this issue does not arise but the u value constraint and the amount of insulation needed is just the same. Add insulation to attic. Choose feldco roofing for your brand new roof. Insulation puts the money back in your pocket by protecting your home from the elements and lowering energy costs.

Hitting amazing levels of 0 13w m will need 300mm of mineral wool or 180mm of rigid foam. Roof slopes 9 12 and higher will require a dry in with a minimum of 3 side laps 12 end laps. Synthetic underlayment may also be used in lieu of a 30 felt provided it is an acceptable substitute to the roofing manufacturer. This insulation strategy has not changed in recent code iterations and is not discussed in this article.

Arkansas enery code for new building construction 3 r 20. Recommended insulation levels for retrofitting existing wood framed buildings. Insulation on the floor of the attic figure 1. State applicable energy ashrae zone minimum r value state local.

R values can be higher for foam insulation and other advanced insulation systems. 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. New rules and practical. Achieving a u value of 0 20w m meaning your roof will be better insulated than your walls will need 120mm thickness of rigid foam or 200mm of mineral wool or natural insulation.

If part of a roof is too low to install insulation that meets the requirements then a less thick insulation product may be used in those low clearance areas. Insulation must keep a distance of at least 25mm from the roof underlay in all parts of the ceiling roof area. 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.