R Rating For Wall Insulation

In most wall applications you will use r 13 or r 15 kraft faced fiberglass insulation rolls for these two by four stud walls.

R rating for wall insulation.

In the context of building and construction the r value is a measure of how well a two dimensional barrier such as a layer of insulation a window or a complete wall or ceiling resists the conductive flow of heat. The r value per inch for different types of insulation varies depending on the. 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. Recommended home insulation r values.

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. 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. For example insulation that is compressed will not provide its full rated r value. R value is a measure of insulation s ability to resist heat traveling through it.

The table below shows what levels of insulation are cost effective for different climates and. Typically a higher insulation r rating means better climate control and better energy efficiency for your home. See the department of energy s doe ranges for recommended levels of insulation below. A higher insulation r value usually means a higher price point as well.

Insulation level are specified by r value. Bulk insulation rated r2 0 70mm or r2 5 90mm can be fitted between studs in the conventional manner and depending on the thickness of the studs and the selected r value may or may not fill the entire wall frame width. It is important to choose the correct thickness of insulation to suit the thickness of the cavity. The higher the r value the better the thermal performance of the insulation.

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. An r value is a rating which measures how well insulation can resist heat flow. R value level depends on a number of things such as the type of material its density and thickness. While there are additional considerations such as venting and moisture problems to take into account when you insulate under floors the united states department of energy recommends an r 25 rating in cold climates and an r 11 in warmer parts of the country.

R stands for thermal resistance.