VELUX roof windows

GLL 85B

VELUX bottom-operated, centre-pivot roof window

GLL 1085B

(interior finish - wood, clear lacquer; exterior cover - aluminum dark gray)

IMPORTANT NOTE: This product is subject to regional limitations, please check availability on the "regions" tab.

The VELUX bottom-operated, centre-pivot roof window GLL 1085B offers a combination of high thermal efficiency and excellent sound insulation. Bottom operation makes it easy to operate the window when installed in a higher position, for example due to a high knee-wall.

The window can be installed in roof pitches between 15° and 90° to the horizontal. Note: A combination of roof pitches, window sizes, cover materials and accessories might hinder parking of the sash in some open positions.

Window Code	Width in mm	Height in mm	Effective Daylight Area in m2	Geometric Free Area in m2
FK06	660	1178	0.47	0.54
MK04	780	978	0.47	0.53
MK06	780	1178	0.59	0.66
MK08	780	1398	0.72	0.81
MK10	780	1600	0.85	0.94
PK08	942	1398	0.92	1.01

Due to the extra sound reduction feature, background ventilation is not possible.

Specifikace

Performance window characteristics	Performance
Thermal transmittance (U-value)	0.90 W/(m²K)

Light transmittance (τ,v)	0.63

Total solar energy transmittance (g-value)	0.45

Sound insulation (Rw)	38(-1;-3) dB

Air permeability, [class]	4

External fire performance - British [class]	AA

External fire performance - European [class	npd

Impact resistance [class]	3

Load-bearing capacity of safety devices	✓

Reaction to fire [class]	C-s1,d0

Resistance to snow load	See glazing composition

Resistance to wind load [class]	C3 (>SK08: NPD)

Water tightness [class]	9A





Glazing unit	Composition (from inside to outside)
Triple-glazed	8 mm float glass - 11.5 mm krypton - 3 mm heat strengthened glass - 11.5 mm krypton - 6 mm toughened glass