ᐅ Insulation beneath the dormer and windows

Hello,

we want to insulate the roof area below our dormer windows, specifically the space under the windows. We have been considering the following:

Wall (about 0.7 m (28 inches) high) under the roof: mineral wool (roll)

Between the rafters:

Insulation batts (roll: 3.3 m (11 feet), 220 mm (8.7 inches), Knauf) or
Insulation batts (pieces: 2 m by 1 m (6.6 feet by 3.3 feet), 220 mm (8.7 inches), Rockwool)
pieces: about 1 m by 0.6 m (3.3 feet by 2 feet), 220 mm (8.7 inches)

However, the 2 m by 1 m insulation batts have the same “volume” as the 3.3 m roll, which seems odd to us. Maybe someone can clarify this and give us a recommendation. We are also considering insulating the dormer wall. A good website on this topic would also be great.

Thank you.

Best regards

Hello,

to be honest, I don’t quite understand the problem 😕

Regards