How and where to use guide
VELUX Recessed Flashings 66x118cm EDN FK06 0000
Where to use this flashing
This recessed flashing is installed around VELUX roof windows in both domestic and commercial buildings. It is specifically designed for use in timber and concrete roof constructions where F16, F24, or F36 timber grades are present. The flashing sits recessed into the roof structure to create a neat, integrated seal. Common installation locations include pitched roofs with valleys, eaves where roof windows meet lower roof sections, and wall corners where windows interface with vertical surfaces. The 66×118cm size suits standard roof window openings; measure your window frame carefully before ordering to ensure correct fit.
- Pitched roofs with roof valleys and multiple roof planes
- Eaves and transitions between different roof levels
- Wall corners and junctions with vertical surfaces
- Domestic loft conversions and commercial roof installations
- Timber and concrete roof structures with F16, F24, or F36 grades
Installation and alignment
Before installation, inspect the roof opening and surrounding structure to confirm it matches the 66×118cm flashing dimensions. The recessed design requires careful positioning so the flashing sits flush with the roof plane and aligns with the window frame. Position the flashing so water will run down and away from the window opening, following the natural slope of the roof. Secure the flashing according to the roof construction type—timber constructions typically use mechanical fixings, whilst concrete may require additional sealant. Ensure all edges are properly sealed to prevent water bypassing the flashing at joints and corners.
- Measure the roof opening and confirm 66×118cm dimensions before fitting
- Align the flashing so it sits recessed and flush with the roof surface
- Orient the flashing to direct water downslope away from the window
- Secure with appropriate fixings for timber or concrete construction
- Seal all joints and edges with suitable roof sealant
Maintenance and limitations
The high-quality plastic construction is durable and resistant to weathering, but regular inspection is recommended, particularly after severe weather. Check that the flashing remains properly seated and that sealant around joints has not cracked or deteriorated. Do not attempt to repair cracks in the plastic flashing itself; replace the flashing if damage occurs. This product is designed specifically for the timber and concrete constructions listed; do not use on other roof types or with timber grades outside F16, F24, and F36. The recessed design means it cannot be retrofitted to roofs where the structure does not accommodate a recessed installation.
- Inspect flashing and sealant annually and after severe weather
- Replace sealant if cracking or deterioration is visible
- Do not attempt to repair cracked plastic; replace the flashing
- Not suitable for timber grades outside F16, F24, F36
- Recessed installation required; cannot be surface-mounted