How to Install Attic Insulation in a Steep Roof

Insulating an attic can be a difficult task, but you can do it yourself with the right tools and little know-how, but really you should call in a professional who has experience with loft insulation or conversions. Attics can be of all shapes and sizes as well as heights. For high peaks, use the back end of a push broom to manipulate the insulation between the rafters. This method can be used for both blanket and batt types of insulation. Blanket insulation types come in rolls while batt insulations are typically 48 inches in length. Applying this method will also be handy in situations where the insulation can be faced or unfaced. Faced insulation has a specially treated paper or aluminum-foil vapor barrier on one side, while unfaced has no backing and requires friction to hold it in place.

If your attic doesn’t have sub-flooring, place wood planks across the joist. Spreading 2-by-4 inch boards across the joist with a sheet of plywood is an acceptable substitute for the planks.

Set up an A-frame ladder so that the legs rest on the planks or the plywood.

If the insulation is faced, climb the ladder and hold the insulation in place with one hand, while using a hammer tacker or staple gun to attach the insulation to the rafters. For unfaced installations, there is no need to tack it into place.

Use the back of a push broom to force the insulation into the peaks of the attic where you’re not able to reach it by hand. In most cases, the insulation will stay in place if it is not tacked, due to the friction between the rafters and the insulation.


Using insulation with a backing will help reduce the itching effects that are common with most fiberglass insulation. Wearing long-sleeved shirts will also protect your skin from fiberglass insulation.