How and where to use guide
VELUX Twin and Combination Flashings 78x140cm EBW MK08 0021B
Typical applications
This flashing is designed specifically for pitched roof window installations where you need to create a weathertight seal around a VELUX window frame. It suits standard rafter spacing and typical domestic roof pitches. The combination flashing function means it handles both the upper and lower water management requirements in a single unit, simplifying the installation process compared to separate flashing components.
- Pitched roof window installations on domestic properties
- Roofs with standard rafter spacing
- Compatible VELUX window models
- Situations requiring dual flashing functionality
Installation and alignment
Correct positioning is essential for weathertight performance. The flashing must be carefully aligned with both your roof pitch and rafter position before securing. The 78x140cm dimensions are engineered for standard spacing, but you must verify compatibility with your specific window model and roof structure before installation. Ensure the flashing sits flush against the roof surface and window frame with no gaps that could allow water penetration.
- Check roof pitch compatibility before installation
- Align flashing with rafter positions accurately
- Ensure flush contact with roof surface and window frame
- Verify compatibility with your VELUX window model
Weather protection and water management
The primary function of this flashing is to create a weathertight seal and manage water run-off on pitched roofs. Water must be directed away from the window frame and roof penetration. The combination design handles water flow from multiple directions, protecting the installation from rain ingress. Proper installation ensures water runs off the flashing and down the roof surface rather than pooling or entering around the window frame.
- Directs water run-off away from window frame
- Prevents water ingress at roof penetration
- Manages water flow on pitched roof surfaces
- Maintains weathertight seal in all weather conditions
Maintenance and on-site tips
After installation, periodically check that the flashing remains properly sealed and that no debris has accumulated around the window frame or flashing edges. Ensure guttering and roof drainage systems are functioning correctly to prevent water backing up against the flashing. If you notice any gaps, movement, or signs of water ingress around the window, inspect the flashing alignment and seal immediately. Keep the roof area around the installation clear of moss, leaves, and other debris that could impede water run-off.
- Check flashing seal and alignment periodically
- Clear debris from roof area around installation
- Ensure roof drainage systems function properly
- Address any signs of water ingress immediately