Your board must leave at least inch gap between the board and the roof.
Using styrofoam for attic roof insulation.
For the same reason insulation shouldn t touch the roof s underside.
Using spray foam insulation in an unvented attic application both low density open cell and medium density closed cell spray foam can be used in an unvented attic to provide the needed thermal resistance and airtightness.
You can use a foamboard adhesive to glue it in place.
Use furring strips nailed into the sides of the rafters so that you have something to fasten the board to.
The superattic system creates a continuous air and insulation barrier directly beneath the attic roof with no thermal bridging to compromise energy performance.
The styrofoam insulation that home depot carries is only rated for r 5 per inch.
The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams and the material will block that flow.
Do not nail the board into the roof.
This is an even more dense and more expensive foam board insulation.
As with attic floor insulation moisture and heat removal are the reasons for creating proper air.
One common use of extruded polystyrene foam board is for foundation insulation panels.
Foam board insulation in the attic can cut down on energy costs and simultaneously promote a more environmentally sound way of daily living.
If you plan on finishing your attic then you cannot install it directly.
Installing foam insulation boards in the attic is no that hard and can save you money compared with professional installation.
2 measure and cut the foam boards as.
Select rigid foam insulation boards that are at least 1 2 inch less in thickness than the rafter space is deep if you plan to finish the attic as living space.
It provides an r value of 6 per inch of thickness and often comes foil faced to help reflect radiant heat.
Polyiso comes in several thicknesses and is used over house sheathing underneath siding or in attic spaces where its reflective properties are very effective.
The superattic system utilizes proprietary silverglo rigid foam insulation panels to fully seal and insulate the attic directly beneath the roof rafters and directly inside the gable ends.
That means even a 2 thick piece will only give you r 10 for 0 96 sq.
I used 20 bags which is the minimum purchase for a free 24 hour blower rental at both hd and lowes.
I just insulated my attic this weekend with blown in cellulose insulation and achieved between r 30 to r 45 for about 0 42 sq.
These insulation materials are not only used to insulate home to bar air from coming in and out but to also protect the space from elements such as mold rodents moisture and dust.