Recommended Wall Insulation Values

In such cases where r value is assigned this may decrease the r value requirement for batt insulation.

Recommended wall insulation values.

You can mix the type and material of insulation too. For example insulation that is compressed will not provide its full rated r value. The insulation must be water resistant and be continuous from the adjacent finished ground level to a depth of 300mm or for at least the full depth of the vertical edge of the concrete slab on ground. Achieving greater r values in attics.

For example a wall with 3 fiberglass batting r value of 10 8 11 9 may have an overall r value of nearly 14 because of siding sheathing and drywall. The overall r value of a wall or ceiling will be somewhat different from the r value of the insulation itself because heat flows more readily through studs joists and other building materials in a phenomenon known as thermal bridging. While wall insulation is limited by the width of the studs different materials provide higher or lower r values. Make sure your home is properly insulated in all these locations.

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. While rated differently these two types of insulation are close enough in thickness that they can both fit into modern two by four wall systems. Insulation level are specified by r value. Department of energy r value recommendations for new and existing homes.

See the department of energy s doe ranges for recommended levels of insulation below. In most wall applications you will use r 13 or r 15 kraft faced fiberglass insulation rolls for these two by four stud walls. The following 2008 department of energy zone recommendations are based on comparing estimated future energy savings to the current cost of installing insulation. The ideal attic insulation r value is different than the ideal wall insulation r value.

Insulation ratings can be improved by adding more layers of insulation. The higher the r value the better the thermal performance of the 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 is a measure of insulation s ability to resist heat traveling through it.

Recommended home insulation r values. Fiberglass batts for standard 2 4 walls are now available in low medium and high density products that range from r 11 to r 15.