Rockwool Roll & Rollbatt U Values

Pitched roof - between & over joists

Prescribed U Value W/m²K

 (England and Wales - Part L 2006) 0.16 extensions, renovation & repair work,
New build requirement could range between 0.13 and 0.12

 
 (Republic of Ireland-Technical Guidance Document 2006 edition) 0.16

(Scotland, with boiler SEDBUK-Part J) 0.16

Ceiling joist	38x100mm		47x100mm
Joist spacing	400mm	600mm	400mm	600mm
Insulation Thickness  mm	U Values W/m2K	U Values W/m2K	U Values W/m2K	U Values W/m2K
100	0.22	0.21	0.22	0.21
150	0.17	0.17	0.17	0.17
170	0.16	0.16	0.16	0.16
200 (100+100)	0.15	0.14	0.15	0.14
250 (100+150)	0.12	0.12	0.13	0.12
300 (150+150)	0.11	0.11	0.11	0.11

Construction: 100mm Rockwool Roll between joists (with the additional thickness
 of Rockwool Roll laid over joists).