How and where to use guide
VELUX Twin and Combination Flashings 78x98cm EKW MK04 S0312
Typical applications and installation
This flashing is primarily used in timber frame construction where weather-tight sealing is critical. It is suitable for installation on rafters, ridge tiles, and other roof components where two roof planes meet or where the roof meets vertical elements. The 78x98cm dimensions make it appropriate for standard residential and light commercial timber frame roof configurations. Installation should follow the EKW MK04 S0312 roofing system specifications to ensure proper overlap and sealing at all junctions. The natural finish timber requires careful handling on site to avoid damage before installation.
- Install on rafters and ridge tiles as part of the EKW MK04 S0312 system
- Use at roof plane junctions and penetration points to prevent water ingress
- Ensure proper overlap with adjacent roof covering materials
- Follow manufacturer specifications for fixing and sealing details
Handling and on-site storage
Grade A timber flashings must be stored flat and protected from weather exposure before installation. Keep the product dry and away from direct sunlight to prevent movement or warping of the natural finish timber. Handle carefully to avoid splitting or damage to edges, as any damage will compromise the watertight seal. Store in a covered, well-ventilated area on site and keep packaging intact until ready for use.
- Store flat in a dry, covered location
- Protect from rain and excessive moisture before installation
- Avoid stacking heavy materials on top of the flashing
- Inspect for damage before installation
Sealing and weatherproofing
The flashing creates a durable barrier against rainwater ingress when properly installed and sealed. The natural finish timber must be sealed or treated according to the EKW MK04 S0312 system requirements to maintain water resistance. Ensure all joints, overlaps, and fixings are sealed with appropriate roofing sealant or flashing cement to prevent water penetration. Pay particular attention to the edges and any cut areas, as these are vulnerable to water ingress.
- Apply sealant to all joints and overlaps as per system specifications
- Seal around fixings to prevent water entry
- Treat cut edges with appropriate timber sealant
- Check seals annually for deterioration in UK weather conditions
Limitations and maintenance
This flashing is designed specifically for timber frame construction and should not be used in applications outside the EKW MK04 S0312 system parameters. The natural finish timber requires periodic inspection and maintenance to ensure the sealant remains effective. The 78x98cm size has defined length and width limits; larger roof areas will require multiple flashings with properly sealed joints. Natural timber is susceptible to movement with temperature and moisture changes, so ensure fixings allow for this movement.
- Use only as part of the EKW MK04 S0312 roofing system
- Not suitable for applications exceeding 78cm length or 98cm width without additional flashings
- Inspect sealant condition annually and reseal if necessary
- Allow for timber movement in fixing design