Insulation Between Roof Joists

Other benefits of roof insulation include.

Insulation between roof joists.

Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing. Once up at roof level the between rafter boards can be cut accurately to fit the rafter spacings. Increasing your home s value. If you put insulation under the decking and between the joists you lower the temperature of the decking and lower the due point thus bringing it closer to the danger point of being in the building.

Convenience polyurethane or polystyrene spray foams can provide thorough coverage to roof rafters and attic walls in much less time than is needed for other materials. 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 will depend on the construction on your roof and if it is a refurbishment whether the roof tiles are going to be removed.

Look for water stains on the roof sheathing or damp or moldy spots on attic joists and existing insulation as a clue to where leaks might be. The underside of the rafters in this case will need to be finished with a suitable vapour control layer vcl and plasterboard to provide a suitable internal finish to the roof. Uneven or sloppy application however can make the insulation ineffective and unsealed open cell insulation can absorb moisture causing the roof to rot or leak. Install batting between the attic s floor joists.

Being lightweight they do not impose significant additional loads on existing structures. We would always recommend having a breathable membrane in place between the tiles and the rafters too to allow the roof to breathe. It creates a breeding ground for mold and mildew and ruins the air trapping pockets that block heat flow. The main difference between the two is the location of the insulation.

Water is insulation s enemy. Where the insulation does not fill the total rafter depth the low emissivity foil facings can gain additional thermal benefit from the air spaces they face. Box out light fixtures. Alternatively battens can be secured to the underside of the joists and gmw fitted between these in much the same way as between the main roof joists.

A warm roof is where it is above and between the rafters so the rafters are kept warm. Improving your home s energy efficiency rating. Insulation between the joists keeps warmth in your living space below and creates a cold loft while insulation in the rafters allows you to keep warmth in the roof space as well.