from [broken link removed]
Only the last last three items in this list can meet the 0.27 W/mK requirement, athough 60mm of TW50 from Kingspan in a cavity will give 0.27 - see note below
Cabity Wall Insulation
100mm blown polystyrene, mineral wool, cellulose fibre
0.30
60mm extruded polystyrene insulation
0.40
35mm polyurethane foam board
0.39
35mm phenolic foam board
0.37
Timber frame 150 mm, mineral quilt
0.25
Timber frame 140mm, cellulose fibre
0.19
Safewarm home construction
0.31
Note the above take no account of building volume, area of heat loss elements or air tightness as described by sydthebeat.
Excellent guide here [broken link removed]
If 60 mm of Kingspan does the job then insulation regulations havent changed that much in the last three three years...??