Fixing and buying guide

What this product is and who needs it

Recessed flashings are essential components that seal the gap between a roof window frame and the surrounding roof material. They prevent rainwater from penetrating the junction, protecting your building fabric and interior. This flashing is for builders, roofers, and serious DIY installers carrying out roof window installation or replacement work on pitched roofs.

Compatibility and sizing

This flashing is sized at 134 x 140cm and is designed exclusively for VELUX timber grade EDJ UK08 0000 roof windows. Before ordering, confirm your window model matches EDJ UK08 0000 – using an incompatible flashing will compromise the weather seal and may void warranties. Check your existing window documentation or contact your supplier if unsure of the grade.

• Size: 134 x 140cm – measure your roof opening to confirm fit
• Compatible window grade: EDJ UK08 0000 only
• Recessed design ensures secure seating on the roof structure

Pre-installation checks and preparation

Inspect the roof opening and existing window frame for damage, rot, or movement before fitting the new flashing. The surrounding roof surface must be clean, dry, and free from debris. Ensure the roof structure is sound and level – any settlement or warping will prevent a proper weather-tight seal. Have appropriate roofing materials ready (slates, tiles, or membrane) to bed the flashing into the roof.

• Check window frame for rot, cracks, or structural movement
• Clean the roof opening and surrounding area thoroughly
• Verify roof surface is level and stable
• Gather roofing materials needed to secure and bed the flashing

Installation and professional finish

The recessed design of this flashing allows it to sit securely within the roof structure, creating a professional appearance and reliable seal. Installation requires careful positioning to align with the window frame and roof slope. Proper bedding into roofing material (mortar, adhesive, or mechanical fixings depending on your roof type) is essential for durability. If you are inexperienced with roof work, engage a qualified roofer to ensure the flashing is installed correctly and the weather seal is effective.