It s a sandwich of rigid foam insulation and plywood or osb oriented strand board the flaky plywood.
Batt insulation lay in attic.
Use cardboard or rigid foam baffles to keep soffit vents open.
Item 305816 model rxss31525.
Position the batt of insulation at the outer edge of the attic and roll the batt in the channel between the joists toward the center of the attic.
While wearing dust mask and gloves carry r 38 batts of unfaced fiberglass insulation into the attic.
Insulation should be rolled out perpendicular to the joists and unfaced rolls should be used.
Don t cover can lights unless they are rated for contact with insulation.
Batt or rolled insulation or blown loose fill insulation fiberglass or cellulose can be installed on top of old insulation.
The paper facing on insulation has an asphalt layer which acts as a vapor barrier.
Any existing batt or roll insulation in the attic should have the facing against the attic drywall floor or no facing at all.
Install baffles against the roof sheathing between rafters so insulation does not seal up these avenues of air circulation.
You only want one vapor barrier in your attic and it should be as close to the ceiling as possible to prevent warm moist air from coming up from the heated house and condensing when it hits the cold air in the attic.
Blown in insulation requires a professional.
There are other materials and systems that you can use to insulate your attic.
Attic insulation is accomplished with either fiberglass blankets batt or blown in insulation.
One that i like a lot since i built a house out of them is the structural insulated panel.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
Lay the batts across the ceiling joists covering the existing insulation.
It s safer to build a small enclosure with hardware cloth or plywood to keep loose insulation away from lights and exhaust fans.
Rockwool safe n sound r 59 7 sq ft unfaced stone wool batt insulation 15 25 in w x 47 in l.
Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.
Continue laying down the insulation making sure the batts are pressed tightly together at all edge and end joints.
Batt insulation is available at home centers and lumberyards.