Our products are rigorously tested during design and development and are compliant with all current building regulations and legislation.

A typical testing regime for a rooflight or flat roof window is similar to that for a vertical window or door and includes air permeability, water tightness and wind resistance.

Additional testing covers safety and impact resistance, which should be in accordance with the Centre for Window and Cladding Technology (CWCT) test protocols. This includes impact tests to assess the effect of both hard and soft bodies on the glazing. Further information can be found on our Specification and Non-fragility page.

What to look for in a quality glass rooflight.

Superb aesthetics and high performance – the basic checklist when selecting a rooflight product.

However, it’s important to look closely at the details and specification of a product. Testing for impact-resistance, durability, environmental and thermal performance, and security and safety performance are essential criteria. 

Glass specification

The first, and safest, choice for the inner pane of a rooflight should be laminated glass

Design details

Look for a glass unit that has specific design details that ensure the unit is fully watertight. Poorly designed frames can lead to water tracking back on the underside of the glass. Flat glass rooflights should also always be installed at a slight pitch to avoid ponding – typically a minimum 5 degree pitch

Thermal break

A ‘true’ thermal break is achieved when a frame design incorporates specific features to achieve the thermal break. The use of foam strips cannot be considered as a true thermal break as these strips may deteriorate over time and therefore their efficacy will be affected.

Thermal performance

The thermal performance of a rooflight must be considered for the whole assembly, because while glazing may be compliant, poor frame design can affect thermal performance.