Roof Rafter Insulation Boards

Install underlay above the rafters.

Roof rafter insulation boards.

Being lightweight they do not impose significant additional loads on existing structures. Depending on the specifics of the roof it may be possible to fully fill the rafter depth or in most cases leave a 25mm or 50mm air gap between the top face of the insulation and the sarking membrane. It comes in standard size 4 8 sheets and smaller sizes in many different thicknesses from 1 4 inch to 2 inches. Our insulation solutions for warm roofs maximise both space and thermal efficiency whilst also contributing to acoustic performance.

Foam board insulation is easy to use and is a great diy way to add some insulation. When they are cut ensure there is a. Celotex polyisocyanurate pir foam insulation boards are easy to cut and handle. Photograph 1 above left.

Measure the space between the rafters where the insulation. Rigid polyisocyanurate pir foam insulation boards from celotex are among the most thermally efficient commonly available insulation materials on the market. Typically made from polyvinyl. Original roof uninsulated rafter framing with board roof deck.

Some types of thicker foam board insulation are available but they may need to be special ordered. For a ventilated roof fix battens on the inside of the rafters 50mm from the underlay to leave vented air spaces. Your rigid boards will need to be cut to fit the gaps between the rafters. Bare foam board one sided sheathing board or double sided which is also reference as structural insulated panels.

For an un ventilated roof construction a vapour open underlay or breather. Insulation is friction fitted between rafters with the option to underline the rafters with a layer of thermal laminate to further enhance thermal performance. Using rigid boards as opposed to wool is a much more precise. Baffles provide a channel for air to flow through certain parts of the attic.

It took us many millennia to get out of caves. Yes skylights went in. This over rafter insulation method also reduces thermal bridging giving an airtight continuous layer of high performance insulation and results in a well insulated attic space. Yes they are big thermal holes.

Insulating the roof above the rafters is known as warm roof insulation as the rafters are brought into the insulated envelope of the building. Baffles are also called wind baffles venting chutes rafter vents or insulation baffles. But a space needs to be a space or what is the point. Again make sure you select the right thickness of the material so you fill as much of the rafter gap as possible.

Furring straightens out rafter plane for smooth plaster finish. Once up at roof level the between rafter boards can be cut accurately to fit the rafter spacings.