How Much Insulation In Garage Walls

If the garage is open to the rafters the boards that support the roof use r 38.

How much insulation in garage walls. Perhaps the easiest way to add insulation to open garage walls is to install fiberglass bats between the studs. 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. Depending on the size of your garage insulating the walls with batts of r 13 will typically run you about 400. They are also commonly available in two thicknesses 3 to fit into 2 x 4 framing or 5 for 2 x 6 studs.

The thicker the better. This is primarily due. Line up the edge of the board at the proper width compress the insulation and cut it with a sharp utility knife. Likely this is one area you shouldn t need to be concerned about as homes by law are built with insulation in the walls.

Insulation for 2x6 walls some newer homes may have walls built with 2x6 studs. Garage walls vary in height which usually means buying rolls of insulation and cutting them to fit. If the joists are 10 inches deep the cavity can take high density r 30 insulation which is 8 1 2 inches thick more than enough for floor insulation. The ceiling might cost another 600 and the garage door will cost about 600 if you do it right.

The insulation in your attic should be at least 12 thick. Most garage walls are framed with 2x4s 16 on center. Use r 19 or r 21 kraft faced fiberglass insulation for two by six 2x6 walls. Note from this chart that the ideal r value differs for each part of your home.

Which leaves a 14 1 2 gap that s 3 1 2 deep in between the studs. There is no 4 inch thick faced fiberglass insulation in batts or rolls on the common market. Use a 4 to 6 in wide board or strip of plywood as a straightedge to guide your utility knife. It is not uncommon to see 15 to 20 of insulation in a well insulated attic.

Bats are manufactured in widths of either 13 to fit in between studs 16 on center or 21 for studs 24 on center. Garage door insulation don t insulate your garage walls and ceiling without insulating the big garage door too. You can use the pink styrofoam stuff from home depot but that will only insulate your door to about r 6. A scrap of plywood under the batt will protect finished floors and keep the blade from dulling on concrete.

Adding insulation to your garage walls is going to be a little more complex of a project. You can buy insulation kits for standard metal garage doors or you can cut pieces of rigid foam insulation to fit each.