Rigid Insulation R Values Per Inch

Asbestos cement shingle siding.

Rigid insulation r values per inch.

Although the nominal r value of polyiso is the highest of the three major types of rigid foam its cold weather performance is lower. For example a wall with 3 fiberglass batting r value of 10 8. Some products have reinforced facing to make them sturdier. Expanded polystyrene foam eps is the cheapest and least used foam board product on the market.

Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system. Let s use the r value of iko s polyiso insulation enerfoil tm as an example. Polyiso is not rated for ground contact. Asbestos lagging and paste will have a lower value.

Most insulation manufacturers will first list their insulation s r value for a one inch sample then they ll give you a chart demonstrating the other r values you can achieve if you install a thicker version of their product. As the temperature drops so does the r value. Choose this option for areas that need a good amount of strength and water resistance. Expanded polystyrene insulation is similar to the foam used for packing peanuts and it s typically used for insulated concrete forms also knows as icf s.

Thermal conductivity k 0 15. In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7. This material offers the highest r values about r 6 to 6 5. Some builders working in cold climates give it an r value of 4 5 or 5 per inch.

Because rigid foam plastic insulation products are not all aged in accordance with the same standards it is useful to publish comparison r value data. Rigid insulation r value by comparison usually ranges from r 4 0 to 6 5 and may get as high as r 8 7 depending on the insulation material. Asbestos cement board r value. The r value for foamular xps insulation is provided from testing at two mean temperatures 40ºf and 75ºf and from two aging conditioning techniques 180 day real.

This product typically has an r value of 3 6 to 4 0 per inch of thickness. Rigid insulation is usually made up of fibrous materials or plastic foams. Traditional loose fill insulation such as fiberglass or cellulose has an r value between r 2 0 and 3 5 per inch of thickness. Estimated r value of asbestos insulation per inch for pipe insulation corrugated paper.

It provides r values that range from 3 6 to 4 2 per inch. The time of testing. For a 1 in thick 4 8 panel comes unfaced or with a number of different plastic facings.