Glazing types and performance

Type	Rw	Rw+Ctr
4 mm float (sealed)	25
6 mm float (sealed)	28
4 mm float, 12 mm cavity, 4 mm float	28	24
6 mm float, 12 mm cavity, 6 mm float	30	26
16 mm float, 12 mm cavity, 8 mm float	33
Guardian Glass 4 mm float, 18 m cavity, 6 mm float	35	31
Guardian Glass 6.76 mm Lamiglass, 18 m cavity, 4 mm float	39	33
Guardian Glass 12.76 mm Lamiglass, 16 m cavity, 6 mm float	43	38
6 mm laminated float, 200 mm cavity with absorptive reveal, 10 mm float	45
17 mm laminated float, 12 mm cavity, 10 mm float	45
Pilkington Optiphon 8.8 mm Optiphon, 20 mm gap, 12.8 mm Optiphon float	47	40
Guardian Glass 10.76 mm Lamiglass, 16 m cavity, 8.76 mm float	47	40
Pilkington Optiphon 12.8 mm Optiphon, 20 mm gap, 16.8 mm Optiphon float	50	47