Roof Insulation R Value Ontario

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.

Roof insulation r value ontario.

R value of various materials. 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. The higher the r value the greater the insulation performance. Newly insulated attic rates at an insulation r value of r 40 or more.

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. Existing 3 4 inches of insulation. Add insulation to attic. All insulation materials in ontario must meet requirements set out by the national government.

Know exactly how much you need with our project calculators. See the department of energy s doe ranges for recommended levels of insulation below. 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. For a very good introductory overview article on r value see r values over at the website of.

Insulation r value is proportional to the insulating material being used. R value measures how well certain building insulation materials can resist heat. The r value of the insulation for every inch of thickness depends on the type 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.

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. Recommended insulation levels for retrofitting existing wood framed buildings. You should of course see the manufacturer provided technical data sheet for the r value of specific products. When determining how much insulation you need don t guesstimate calculate.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. The recommended r value for attic insulation in ontario is between r 50 and r 60. The two distinct types of attic insulation are loose fill material also commonly known as blown in insulation and batting. In such cases where r value is assigned this may decrease the r value requirement for batt insulation.