What Is The Highest R Value For 6 Inch Batt Insulation

The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13.

What is the highest r value for 6 inch batt insulation.

Polyisocyanurate polyurethane foam insulation r values. Closed cell spray foam has a far better r value per inch than other less effective insulations like cellulose fiberglass or even open cell foam. High density sidewall batts are available in sizes to fit standard construction without loss of r value due to compression. Insulation or other building material 9.

It has a lower r value per inch than closed cell foam and is vapor permeable. 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. Rigid foam insulation comes in various materials including polystyrene r 3 8 to r 5 0 polyurethane r 5 5 to r 6 5 and polyisocyanurate r 5 6 to r 8 0. There is no 4 inch thick faced fiberglass insulation in batts or rolls on the common market.

For higher r. High density cathedral ceiling batts allow an airspace between the insulation and roof deck for ventilation. For example a wall with 3 fiberglass batting r value of 10 8. This means for example that pink batts ultra r4 0 insulation is more effective than pink batts classic r1 8 insulation.

Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system. These batts meet the energy saving requirements of today s codes without requiring changes in construction. In order to achieve the higher insulation r value of r 21 a different type of. The higher the r value the better the insulation is at reducing heat flow.

Closed cell spray foam insulation. 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 in your attic to reach r 30 if you live in zones 2 or 3. Pink batts classic is our lower r value range of insulation designed to achieve minimum building code requirements. In this case use r 13 or r 15 fiberglass insulation.

Fiberglass blankets or rolls provide an r value of up to 3 2 per inch so a 6 inch fiberglass batt may achieve an r value of 19 2 and some high performance products. Unfinished foundation and basement walls are typical applications for these boards which only require two to three inches to achieve the recommended r 11 for basement. Aging effects comments. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

Older homes especially those pre dating the 1950s may employ two by fours that truly are 2 inches by 4 inches.