Proper Placement Of Attic Insulation

Rafter vents or insulation baffles install in any rafter space to create narrow gaps that direct fresh air from the soffit vents to the peak of the roof.

Proper placement of attic insulation.

Doubled vapor barriers in attic. If it s jammed too tightly into a cavity it can t trap as much air and won t be as effective. The key to proper ventilation of your roof and attic is balance. Fiberglass insulation gets its r value from the amount of air it traps between its fibers.

Look for water stains on the roof sheathing or damp or moldy spots on attic joists and existing insulation as a clue to where leaks might be. Placing a radiant barrier directly under the roof decking as illustrated above raises the attic temperature and energy consumption between 2pm and 8pm. In addition insulation baffles must be installed at the point where the attic floor meets the roofline to prevent the attic insulation from migrating into the cavities and restricting the airflow from the soffit vents. We include cape style building roof attic knee wall insulation advice or for homes with no basement crawl space insulation placement advice basement insulation advice.

By the mother earth news editors. Laying a second layer of fiberglass batts in the attic is an easy way to boost r values. If your attic has enough insulation and proper air sealing and your home still feels drafty and cold in the winter or too warm in the summer chances are you need to add insulation to the exterior walls. The reason is simple when the inside roof deck surface emissivityis lowered from 95 bare wood to a lower value the result is a hotter substrate hence the logic behind the radiant barrier.

This article describes the optimum placement of building insulation for various building designs problem spots and hard to insulate or hard to ventilate building spaces. It creates a breeding ground for mold and mildew and ruins the air trapping pockets that block heat flow. Box out light fixtures. The answer is rafter venting.

This guide to proper attic insulation includes tips on vent areas right side up puckers loose or compressed insulation animal nests mold and more.