Foam Board Insulation In Attic Rafters

Smaller sizes are also available.

Foam board insulation in attic rafters.

They re much lighter and easier to work with than plywood sheets. 2 snap a chalk line between the length measurements. Some types of thicker foam board insulation are available but they may need to be special ordered. Loose fill or batt the common term for blanket insulation.

Measure the length and width between two rafters in your attic and transfer the measurements to a 4 ft by 8 ft of rigid foam insulation board. For diy attic insulation you ve got two choices. Typical thicknesses range from inch to 2 inches with estimated r values of r 3 for the inch to r 10 for the 2 inch board. Once you ve decided which type is best for you examine the material options and prices to home in on the right product.

It is lightweight and easy to work with. Better than spray foam thermal break and relatively consistent r 30. The superattic system creates a continuous air and insulation barrier directly beneath the attic roof with no thermal bridging to compromise energy. By adding the insulation under the rafters to maintain a ventilated roof at a cost of say1600 for a r28 airsealed radiant barrier product with the ability to add more if needed at a later date how is that a bad idea if an air sealed attic floor w blown in will cost roughly the same and i still won t have a good environment for hvac etc.

Here s how to use 3 layers of 2 inch polyiso foam board to meet code and keep your ne. Foam board insulation is easy to use and is a great diy way to add some insulation. Polyurethane or polystyrene spray foams can provide thorough coverage to roof rafters and attic walls in much less time than is needed for other materials. It comes in standard size 4 8 sheets and smaller sizes in many different thicknesses from 1 4 inch to 2 inches.

A 4 by 8 board weighs next to nothing and can easily be cut to fit. For new construction use rigid boards to insulate slabs and the outside of foundation walls. Install them using panel adhesive or screws. Both can be added to uninsulated attics or layered over existing material.

Unlike solid insulation products that require careful measurement cutting and fitting spray foam can cover even the most uneven surface instantly.