Roof Insulation R Value Ontario

Foam plastic insulation on the interior of the building envelope must adhere to the requirements of protection of foamed plastics as per 9 10 17 10 of the national building code of canada.

Roof insulation r value ontario.

For a very good introductory overview article on r value see r values over at the website of. When determining how much insulation you need don t guesstimate calculate. The two distinct types of attic insulation are loose fill material also commonly known as blown in insulation and batting. R value measures how well certain building insulation materials can resist heat.

See the department of energy s doe ranges for recommended levels of insulation below. Add insulation to attic. A bare concrete wall basement foundation rates at an insulation r value of about r 1. R values of common types of insulation.

The higher the r value the greater the insulation performance. All insulation materials in ontario must meet requirements set out by the national government. Ontario building code sb 12 insulation requirement increases so now we need to figure out the most effective use of materials to get to r24 in the exterior walls. The r value of the insulation for every inch of thickness depends on the type of insulation.

Existing 3 4 inches of insulation. 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. R value roofs without attic space insulation above deck u 0 032 r 30 0 ci u 0 028 r 35 0 ci with attic space and other u 0 021 r 50 0 u 0 017 r 60 0 walls above grade above grade walls u 0 055 r 13 0 r 10 0 ci u 0 055 r 13 0 r 10 0 ci wall below grade. To be available on the market manufacturers take care of this step before their products are even available which is why it s important to ensure you re buying new insulation and not dead stock found in someone s garage.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. R value of various materials. Newly insulated attic rates at an insulation r value of r 40 or more. You should of course see the manufacturer provided technical data sheet for the r value of specific products.

In such cases where r value is assigned this may decrease the r value requirement for batt insulation. I m figuring that 2x6 with r20 1 r5 insulated sheathing will be cheaper than 2x4 with sprayed urethane r7 per inch r24 5 but will need to be analyzed. The recommended r value for attic insulation in ontario is between r 50 and r 60. Recommended insulation levels for retrofitting existing wood framed buildings.