External Venetian Blinds

External venetian blinds

External venetian blinds consist of thin, deep, metal (often coloured) slats that can be controlled to allow views out, whilst still providing solar control. Slat tilt angles control privacy levels too. When retracted, slats stack in a box installed in the window head, leaving the window fully exposed.

General properties

Thermal comfort Overheating prevention	*****	Reduces solar radiation up to 96 % (*) when fully extended. Effective in all facade orientations
Thermal comfort Passive heating Insulation	*****	External venetian blinds provide an additional layer of insulation helping to keep warmth inside and reduce heating costs. How strong that effect is depends on the type of glazing behind it.
Visual comfort Daylight	****	The thin slats maximise the free area to allow daylight ingress. In winter it allows maximum daylight when fully retracted.
Night cooling Ventilation	***	In combination with an open window the gaps between the slats allow for a degree of ventilation, but it will mainly depend on the free area between the slats, the tilt angle and how much the blind is extended.
Wind resistance	*****	Side-channel systems are much more wind resistant than cable systems, making them the preferred choice for exposed facades or higher buildings.
Operability	*****	External venetian blinds perform best when operated automatically, maximising energy savings and comfort.
Maintenance	*****	Inspect channels and lift tape. Access to the motor in the blind box is required.