How To Insulate Between Roof Rafters

When they are cut ensure there is a.

How to insulate between roof rafters.

If your attic is going to be converted into livable space then you will need to insulate the roof rafters. Step 1 measuring the space. Step 2 cutting and fitting the insulation. Cut each piece of insulation an inch or two longer than needed to assure a snug fit.

In this blog post we will be looking at insulating pitched roofs and why putting insulation just between the rafters isn t a viable solution. How to install rafter insulation. A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel. You can also add rigid foam insulation under the rafters which adds r value and eliminates thermal bridging through wood rafters.

Once you have these in place measure the length of the spaces between your rafters. The flexible nature of gmw means that the roll or batts can be accurately cut and friction fitted between the rafters thereby minimising air gaps and maximising thermal performance. The general advice we give is that you should always insulate between and above the rafters warm roof or between and under the rafters cold roof. Install ventilation baffles into the space between the rafters before you install the insulation usually by stapling into place.

Isover glass mineral wool gmw is another option for the between rafter insulation as a roll or batt. Using rigid boards as opposed to wool is a much more precise. Attach baffles to the bottom of the roof sheathing the plywood or solid wood strips onto which roofing material was installed. Step 3 installing the insulation.

Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing. First climb into the attic and use measuring tape to determine the square footage of the space. Your rigid boards will need to be cut to fit the gaps between the rafters. Measure the space between the rafters where the insulation will be placed and cut the insulation boards marginally wider than the space to ensure a friction fit upon installation.

Don a long sleeved shirt safety glasses gloves and a dust mask to prevent irritating fiberglass from reacting with. Again make sure you select the right thickness of the material so you fill as much of the rafter gap as possible.