I'm replacing the kitchen ceiling in our single storey extension and wondering about beefing up the insulation.
It's a shallow-pitched, tiled roof with 9cm Kingspan between the rafters and air gap above (under the felt) for ventilation.
The Kingspan is friction-fitted but not very accurately cut in some places.
I reckon for about £95 + battens I could add a Tri-Iso type foil layer before plasterboarding. But is it worth it? Is there enough Kingspan to do the job even with the minor gaps?
Ta for any advice.