Average roof insulation costs for spray foam is around 55 per m2 whereas roof insulation panels are around 25 per m2.
Loft insulation roof rafters.
You can use rigid insulation board carefully cut to size or you can have foam insulation sprayed between the rafters.
Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing.
An alternative way to insulate your loft is to fit the insulation between and over the rafters these are the sloping timbers that make up the roof itself.
A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel.
When people refer to roof insulation they are referring to the barrier of material within your roof space either between the joists or rafters.
When you use solid insulation board to create a warm loft the key thing to remember is ventilation you must keep a 50mm gap between the roof and the rigid insulation board.
Roof insulation cost roof insulation is the same as loft insulation.
The materials used to insulate under the roof include batts of mineral or glass wool insulation held in place by battens of wood attached to and across the rafters alternatively polystyrene.
If the loft is going to be used as living space then the insulation should be placed at rafter level to create a warm roof.
It can either be laid between the joists the horizontal beams along the floor of your attic or the rafters the angled beams that support the roof.
An efficient room in a roof in a new build property where over rafter insulation is not desirable a refurbishment of an existing roof with head room to spare below the ceiling or a project converting a loft space into a room in the roof.
You can also add rigid foam insulation under the rafters which adds r value and eliminates thermal bridging through wood rafters.