How To Insulate Hip Roof

Place the plastic sheeting on top of the rolled insulation.

How to insulate hip roof.

For rolled insulation place it between roof rafters. I was going to make a ceiling and insulate on top of that but the top of the roof at its highest point will be only about 3 feet above the floor of the attic at the center of the garage. I have a 18 x24 garage i want to insulate. I would recommend that you install them the full length from the lowest part of the attic to where there is an adequate air space existing.

The right way to insulate attics and cathedral ceilings with batts using certain t. Cut each run to the proper length. Airspace from the soffit to the ridge by installing a continuous air chute in each rafter bay. Then feed the rolled insulation under wires and pipe if either is present.

If 180mm is to be installed then 100mm board might be introduced between the rafters there has to be a minimum 25mm air gap between the insulation and the underside of the tiles or slates with an 80mm board running across the rafters. In the case of a cold roof structure the insulation is placed between or between and under the rafters or at ceiling joist level and the roof is ventilated by leaving a 50mm gap above the insulation which vents air to the outside. Allow insulation to overlap the top plate of the exterior wall and for additional protection install insulation across the tops of joists as well. To install the air chutes staple them directly to the roof decking.

Air chutes when combined with soffit vents and a ridge vent will help prevent problems with condensation and ice dams. Make sure it is flush against the wood as even a 1 inch gap can cause a 20 percent heating loss. With a warm roof the usual process is to split the insulation into two layers. To effectively ventilate your roof create a 1 in.