Fixing and buying guide

What this product is and who needs it

This is a roof flashing kit for installing VELUX roof windows or Sun Tunnel systems through single plain tile roofing. It is essential for anyone fitting a compatible VELUX window into a pitched roof with plain tiles, whether you are building new or carrying out refurbishment work. The flashing prevents water ingress and provides a neat, finished appearance where the window frame meets the roof tiles.

Compatibility and sizing

This flashing is engineered specifically for VELUX roof windows and Sun Tunnel systems with a 78×98cm opening size. It is designed for single plain tile roofs where the tiles are up to 14mm deep. Before ordering, confirm that your roof window opening matches this size and that your roof tiles fall within the 14mm depth specification. If your tiles are thicker or your window opening is different, you will need a different flashing kit.

• Window opening size: 78×98cm (780×980mm)
• Maximum tile depth: 14mm
• Roof type: Single plain tile only
• Compatible with: VELUX roof windows and Sun Tunnel systems

What is included in the pack

The kit comes complete with all components needed for installation. The BDX and BFX installation products are included, meaning you do not need to source additional flashing components or sealing products separately. This integrated approach ensures all parts are designed to work together for a reliable weather-tight installation.

• Single plain tile standard flashing
• BDX installation component
• BFX installation component

Pre-installation checks and preparation

Before fitting, measure your roof opening carefully to confirm it is 78×98cm and check that your plain tiles are no deeper than 14mm. Inspect the roof structure around the opening to ensure it is sound and level. Have the VELUX window unit ready and check that it is compatible with this flashing kit. Ensure you have appropriate roof access equipment and that weather conditions are suitable for working at height. Familiarise yourself with the installation instructions provided with the kit, as correct fitting of the BDX and BFX components is critical to achieving a weather-tight seal.