Flat Roof Insulation Board R Value

You can even place it under the foundation slab.

Flat roof insulation board r value.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. Note from this chart that the ideal r value differs for each part of your home. Rigid insulation is one of the best tools to reduce your energy costs. This also means easy hoisting staging and maneuvering around the roof.

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. They keep your home at a comfortable temperature without the need to crank your heat. 2020 insulation cost estimate foam board insulation prices the average cost of flat roof insulation is 0 67 per square foot for 1 inch thick polyiso with 6 r value. For a 1 inch board equivalent of 6 r value.

For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed your attic to reach r 30 if you live in zones 2 or 3. To convert rsi to r value multiply the rsi by 5 67826. We recommend having at least 20 r value worth of material for optimal energy efficiency. R value of various materials.

To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. It is top quality and the most cost effective product for your flat roof. Combining different types of insulation to increase r value. You can expect to pay about 55 100 sq ft.

Composite insulation works in flat and low sloped roofs with a variety of roof coverings. Rigid foam insulation also known as insulating boards provide high r values. Protector hd allows easy efficient scoring cutting and snapping which permits fast tight fabrication and all in a low dust environment. For a very good introductory overview article on r value see r values over at the website of.

You should of course see the manufacturer provided technical data sheet for the r value of specific products. High quality rigid foam insulation that is properly installed will greatly improve ventilation eliminate drastic temperature fluctuations inside the home and protect from leaks. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1 93721. Install it anywhere from the roof to the foundation.

Provides significantly more thermal insulation r value than wood fiber or gypsum boards. High r value 2 5 r.