How and where to use guide
VELUX Twin and Combination Flashings 78x98cm EKL MK04 S0312
Typical applications and installation
This flashing is used during VELUX skylight installation to seal the gap between the skylight unit and the surrounding roof structure. It sits at the interface between the skylight frame and the timber rafters or roof deck, directing water away from the internal structure and into the roof drainage system. The flashing must be installed before roof covering materials such as tiles, slates or felt are fitted. Installation requires careful alignment with the 78cm x 98cm skylight opening to ensure complete coverage and a secure seal.
- Install the flashing during the initial skylight fitting, before roof covering is applied
- Position the flashing to overlap roof covering materials to direct water outwards and downwards
- Ensure the flashing sits flush against the timber structure to prevent gaps or movement
- Use appropriate fixings to secure the flashing firmly to the roof structure
Compatibility and structural requirements
This flashing is specifically engineered for VELUX skylights of 78cm x 98cm dimensions and is compatible with timber roof structures graded F16, F24 and F32. These timber grades indicate the structural strength and load-bearing capacity of the roof timbers. Verify that your roof structure meets these specifications before ordering. The flashing will not perform correctly if installed on incompatible skylight sizes or timber grades.
- Confirm your VELUX skylight is 78cm x 98cm before purchasing
- Check that roof timbers are graded F16, F24 or F32
- Do not use this flashing with other skylight brands or sizes
Durability and maintenance
The powder coat finish provides excellent protection against corrosion, weathering and UV damage, ensuring the flashing maintains its integrity over many years. The plastic material resists rust and degradation in wet conditions. Periodically inspect the flashing from inside the building to check for any signs of water staining or leakage around the skylight frame. Clear any debris such as leaves or moss from the flashing surface to maintain effective water drainage.
- Inspect the flashing annually for signs of water ingress or damage
- Keep the flashing surface clear of debris and moss to maintain water flow
- Do not attempt to repair or modify the flashing; replace if damaged
- The powder coat finish requires no special maintenance or treatment
On-site handling and safety
Handle the flashing carefully during transport and installation to avoid denting or bending, which could compromise the watertight seal. Ensure the flashing is stored in a dry location before installation. When working at height on the roof, follow all relevant health and safety procedures and use appropriate fall protection equipment. Do not force the flashing into position; it should fit securely without excessive pressure.
- Store the flashing indoors and keep dry until installation
- Handle carefully to avoid damage to the powder coat finish
- Use appropriate roof access equipment and fall protection when installing
- Work in dry conditions to ensure proper fitting and sealing