Installation

Installation of insulating glass units

Insulating glass units should be installed in accordance with BS 6262 and the manufacturer's instructions. Correct installation is essential to ensure the long-term performance of the unit.

General principles

• The frame must be capable of supporting the weight of the unit and resisting the design loads.
• The rebate must be drained and ventilated to prevent the accumulation of water around the perimeter seal of the unit.
• The unit must be supported on setting blocks of an appropriate size and material, positioned at the quarter points.
• The unit must not be in direct contact with the frame; appropriate location and distance blocks must be used.
• The glazing gasket or sealant must be compatible with the perimeter seal of the unit.

Setting blocks and location blocks

Setting blocks support the weight of the unit and must be of a suitable hardness, typically 80 to 90 Shore A. Their length should be at least equal to the thickness of the unit. Location blocks are used to centre the unit in the frame and prevent movement.

Drainage and ventilation

The glazing rebate must be drained to prevent water from sitting against the perimeter seal of the unit. Drainage slots should be positioned at the bottom of the rebate. Ventilation slots should be provided to allow the glazing cavity to dry out.

Compatibility

All materials in contact with the perimeter seal of the unit (sealants, gaskets, tapes) must be compatible with the seal. Incompatibility can lead to premature failure of the seal and unit failure.