First strip the old roof and cover it with a peel and stick roofing membrane.
Retrofit room in roof insulation.
But even though an unconditioned roof won t benefit from being covered in foam it will need to be detailed so that it aesthetically matches the rest of the roof retrofit work.
Hack n stack sealed foam board between the rafters would be better since it s at least an air impermeable insulation but even that would require a vent gap below the roof deck to meet code and you d still be under r38 on that 2x6 rafters unless you.
Insulation is shown in plane of rafters where existing roof membrane is non breathable.
Close off the rafter bays with rigid foam or plywood.
Detail for insulation installed to the ceiling of a room in roof to replace existing thin insulation to increase thermal efficiency and prevent heat loss through the roof of the building.
The first order of business to to strip the roof.
Retrofit room in roof insulation is now established as a common energy efficiency measure in the domestic sector.
Batts between rafters in would require adding ventilation between the insulation roof deck.
Remove enough siding so that you can get to the house wrap and seal.
This guide is intended to supplement annex b12 of pas2030 2017 to offer more specific advice.
Dry in the roof with peel and stick membrane install two layers of insulation to the roof staggering the seams.
Next cut off the rafter tails so that the connection between roof and walls can be sealed with peel and stick membrane.
25mm or as shown on detail.
Within this annex it recommends that installers take account of guidance provided in a guide to retrofit room in roof insulation the new guidance.
Improving the thermal performance of a home with retrofit insulated panels can be one part of a comprehensive energy retrofit.
Next cut off the rafter tails.
For larger roofs you may need to provide direct framing to framing contact.
This will make a simpler shape for the air barrier.
Ensure adequate ventilation between insulation and roofing membrane minimum.
Roof insulation retrofit codes for existing buildings and air sealing tape choices the fine homebuilding editors discuss framing details for adding rigid foam over a roof when a remodeler needs to refer to the international existing building code what tapes work well for weatherizing an attached garage and more.
The project can include adding new windows additional roof insulation air sealing and upgrading heating and cooling equipment or merely be an energy efficient component of a re siding job.