Combining Keylite Roof Windows

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Combining Keylite Roof Windows

Keylite’s range of Combination Flashing Systems allows any of the standard Keylite Roof Windows to be installed in vertical, horizontal or group blocks.

Features & Benefits

  • Suitable for roofing materials with a profile height of between 10-90mm
  • All weather and UV ray resistant
  • Ensures a watertight connection with the roof
  • Recessed installation as standard
  • 10-year hassle free guarantee
  • Can be manufactured to accommodate 18mm gaps with additional support trimmer for side by side installations
  • Variations and specials on request; please contact the Keylite Sales Team for more information.

Configuring Combinations

Step 1

Choose your roof windows

There are 4 factors to consider when buying your roof window from Keylite:

Step 2

Choose your window layout

There are 3 main window layouts available:

Combi System
Side by side on a horizontal plane.

Bi-Lite System
One over the other on a vertical plane.

Grid System
Multiple windows in grid formation.

Step 3

Spacing between windows

  • 100mm
  • 50mm (Combi System only)
  • 18mm (Combi System only)

Step 4

Type of Flashing

  • Tile Roof
  • Slate Roof
  • Plain Tile Roof (Combi System only)

Step 5

Support Trimmer Finish

Choose between White or Pine Internal Support Trimmers.

Available Combinations

Side by side

Side by side on a horizontal plane. Available with a 100mm, 50mm or 18mm gap and all flashing kits. Great for buildings with a slim roof.

Over & Under

One over the other on a vertical plane. The roof windows situated in a vertical column can be different lengths but must be the same width.

100mm gap only

Grid System

Grid Systems are simply extensions of a Quad-Lite system. Unlike the Quad-Lite system, the distance between all roof windows whether on a horizontal or vertical plane must always be 100mm.


Quad-Lites are simply an amalgamation of the Combi and Bi-Lite systems. Identical to the Bi-Lite system, the lengths of the roof windows can vary in a vertical column but not in a horizontal row.

Combi Ridge

Combi Ridge roof windows may be installed along the roof ridge to maximise light and space at the highest point of the pitched ceiling and create a striking feature.

Dormer Apex System

The Keylite Dormer System creates a well ventilated and bright space.

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Vertical Bi-Lite

The ideal way to maximise the light and ventilation into any room.


Ridge System

Keylite Ridge Systems are ideal for both domestic and commercial applications.


Service & Support

Our technical experts are on hand to advise and assist you at the design and specification stage.

Patented Innovation

Our patents mean that other conventional roof windows do not share many of our extraordinary features.

Up to 20 Year Guarantee*

We are confident that our products will give trouble free performance throughout this period and beyond. *See Guarantee terms

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Available in
Great Britain, Northern Ireland & Republic of Ireland

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