Insulating Attic Joists

They have floor joists or the bottom chords of roof trusses with drywall below.

Insulating attic joists.

Batting comes in rolls and is sized to fit between rafters or joists. If the air distribution is in the attic space then consider insulating the rafters to move the distribution into the conditioned space. Fill the entire depth of the joists with insulation. 1a attic access door.

Always cover the tops of the ceiling joists to make sure the insulation is deep enough to reach your target r value and. Although it s common to talk about installing insulation on the attic floor most attics don t really have a floor. Either batting or blown insulation works in attics. Check the insulation manufacturer s instructions for the necessary thickness of plastic.

You can lay fiberglass sold in pre cut batts or rolls that you cut to size into the joist cavities or pour in loose fill insulation cellulose is the most common type although you can occasionally find glass fiber and rock wool. More insulation installation tricks and tips work from the perimeter of the attic toward the door or hatch so that you don t trample all over the insulation you just. In practical terms you can choose between mineral wool or insulation boards. If you decide on mineral wool such as glass wool or rock wool you will need to put down a damp proof membrane.

In an unfinishedattic the most effective method is to add insulation between the joists of the attic floor. Overlap the seams by about 12 inches and run the plastic up the walls at least 6 inches. Spread plastic sheeting over the crawlspace floor to block ground moisture from entering the area. So insulating the floor of the attic is not only the best solution but it is also the simplest and cheapest.

When unrolled batting assumes its loft or thickness. Standard joist spacing for the installation of attic flooring materials is 16 inches on center oc meaning the distance from the center of one joist to the center of the next joist is 16 inches. Add new insulation if your attic has no insulation install either foil or kraft paper faced fiberglass rolls or batts in between all the attic floor joists which are also the ceiling joists of the rooms below.