Minimum Roof Insulation Irc2009

13 5 means r 13 cavity insulation plus r 5 insulated sheathing.

Minimum roof insulation irc2009. Minimum insulation r value requirements non residential above roof deck. State applicable energy ashrae zone minimum r value state local ms mississippi ashrae 90 1 2010 2 r 20 3 r 20 state local mo missouri 2012 iecc 4 r 25 5 r 25 state only mt montana 2012 iecc 6 r 30. The thickness of blown in or sprayed roof ceiling insulation fiberglass or cellulose shall be written in inches mm on markers that are installed at least one for every 300 ft 2 28 m 2 throughout the attic space. The markers shall be affixed to the trusses or joists and marked with the minimum initial installed thickness with numbers a minimum of 1 inch 25 mm high.

Where section n1102 1 would require insulation levels above r 30 and the design of the roof ceiling assembly does not allow sufficient space for the required insulation the minimum required insulation for such roof ceiling assemblies shall be r 30. Fasteners for asphalt shingles shall be galvanized steel stainless steel aluminum or copper roofing nails minimum 12 gage 0 105 inch 3 mm shank with a minimum 3 8 inch 10 mm diameter head astm f 1667 of a length to penetrate through the roofing materials and a minimum of 3 4 inch 19 mm into the roof sheathing. Minimum insulation fastening requirements adhered membrane to qualify for a 55 mph jm peak advantage guarantee max. Where the roof sheathing is less than 3 4 inch 19 mm thick the.

20 year term the following requirements represent the minimum fastener and plate attachment criteria to qualify for a 55 mph jm peak advantage guarantee up to a 20 year term. At eaves and gables rakes and extend a minimum of 2 inches onto the roof deck and a minimum of of an inch below the roof sheathing. Or insulation sufficient to fill the framing cavity r 19 minimum. 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.

Minimum insulation r value requirements by state. This reduction of insulation from the requirements of section n1102 1 shall be limited to 500 ft. Basement wall insulation is not required in warm humid locations as defined by figure 301 1 and table 301 1. If structural sheathing covers 25 percent or less of the exte rior insulating sheathing is.

Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities. In irc s 2006 and 2009 editions a requirement was. Code for residential buildings that creates minimum regulations for one and two family dwellings of three stories or less. Drip edges need to be attached at a maximum of 12 inches on center.