Most effective dormer loft insulation?

[mk83]

In the roof and in the walls?

We have experienced that with regular insulation it is still too hot in summer and too cold in winter.

Any help would be greatly appreciated as we are about to modify our existing loft conversion into a dormer.

Thanks

 

[tony1851]

We have experienced that with regular insulation it is still too hot in summer and too cold in winter.

You probably dont have enough insulation.
The best for lofts is Kingspan / Xtratherm etc. One or two inches between the rafters, and 1" or so underneath would give some improvement (though not up to current Building regs).
Check ventilation at eaves.
Don't bother with the multifoil products, they're a waste of time and space.

 

[freddiemercurystwin]

Even new build houses with room's in the roof are hot in the summer. They're generally warm in the winter though but the warm in the summer bit you generally just have to put up with. Stick with Celotex or Kingspan and you'll not go far wrong. No point going more than about 150mm as the additional returns will be negligible.