Should You Insulate Between Roof Rafters

Install ventilation baffles into the space between the rafters before you install the insulation usually by stapling into place.

Should you insulate between roof rafters.

If your attic is going to be converted into livable space then you will need to insulate the roof rafters. The rafters are joined together by a horizontal ridge board at the top and tied together by ceiling joists at the bottom. Make sure it is flush against the wood as also a 1 inch gap can create a 20 percent heating loss. You can add insulation to the floor.

The current trend is for a warm roof where insulation is installed between the rafters thereby keeping the roof timbers warm. The will hold open an air gap of approximately 1 inch to allow airflow past a layer of insulation. Usually you will certainly fill the insulation blower with the insulation and blow it between the attic floor joists. The ones i ve used are made of styrofoam and iirc they cost around 2.

Insulating the rafter space will give you a warm loft. For rolled insulation location it in between roof covering rafters. You can use rigid foam panels or do as tom silva does with nearly all houses these days. In order to avoid damage to the roof deck you should insulate ceilings to create an air barrier between the living space and an unfinished attic or airspace underneath the roof deck.

Hire a pro to install spray foam insulation. Attic moisture problems are often the result of heated air from the living space rising up into the attic which is not heated. You can also add rigid foam insulation under the rafters which adds r value and eliminates thermal bridging through wood rafters. A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel.

This means insulating between or below the sloping beams that form the construction and support a sloping roof. Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing. If you re considering turning your attic into conditioned storage or living space it s worth changing tactics to insulate between the rafters and wall joists instead of the floor.