Hello,
we have purchased an old house where the roof is currently insulated with aluminum-coated insulation wool placed between the rafters.
The roof tiles are laid on wooden battens. In the upper roof area, there is a ventilation tile installed in each rafter bay.
We would like to re-insulate the roof from the inside because the old insulation is partly falling out and torn.
However, the roof will only be re-covered in 5-8 years.
My question is whether it makes sense to install 120mm (5 inches) of insulation batts between the rafters (rafter height is 140mm (5.5 inches)) plus an additional 50mm (2 inches) of insulation below the rafters,
or if it would be better to double the rafters and install 180mm (7 inches) of insulation batts from the inside.
In both cases, of course, with an interior vapor control layer and an appropriate finish with drywall/plasterboard (Rigips/Fermacell).
The idea would then be to add further insulation from the outside later with a wood fiberboard when the roof is replaced.
Thank you very much in advance. Best regards from the North
we have purchased an old house where the roof is currently insulated with aluminum-coated insulation wool placed between the rafters.
The roof tiles are laid on wooden battens. In the upper roof area, there is a ventilation tile installed in each rafter bay.
We would like to re-insulate the roof from the inside because the old insulation is partly falling out and torn.
However, the roof will only be re-covered in 5-8 years.
My question is whether it makes sense to install 120mm (5 inches) of insulation batts between the rafters (rafter height is 140mm (5.5 inches)) plus an additional 50mm (2 inches) of insulation below the rafters,
or if it would be better to double the rafters and install 180mm (7 inches) of insulation batts from the inside.
In both cases, of course, with an interior vapor control layer and an appropriate finish with drywall/plasterboard (Rigips/Fermacell).
The idea would then be to add further insulation from the outside later with a wood fiberboard when the roof is replaced.
Thank you very much in advance. Best regards from the North