Fixing and buying guide

Who this is for and what it does

This flashing kit is for builders, roofers, and serious DIY installers fitting Velux roof windows or Sun Tunnels into pitched roofs with single plain tiles. The flashing creates a weather-tight seal around the window or tunnel opening, preventing water ingress and ensuring a professional finish. It is suitable for both new build installations and refurbishment work on existing properties.

Compatibility and sizing

This flashing is designed for single plain tile roofs where tile thickness does not exceed 14mm. It is compatible with standard Velux roof window and Sun Tunnel systems. The flashing dimensions are 660×1400mm, which suits the FK08 2000 Pro+ window size range. Before purchasing, confirm that your roof tiles fall within the 14mm thickness specification and that your Velux window model is compatible with this flashing type. Check your window documentation or contact Velux technical support if you are uncertain.

• Maximum tile thickness: 14mm
• Flashing dimensions: 660×1400mm
• Compatible with Velux roof windows and Sun Tunnels
• Not suitable for interlocking tiles, slate, or thicker plain tiles

What is included

The kit is supplied complete with all components needed for installation. The BDX and BFX components are included, eliminating the need to source additional parts separately. This ensures you have everything required for a professional, weather-tight installation.

• Flashing base unit
• BDX component
• BFX component

Pre-installation checks

Before fitting, inspect your roof tiles to confirm they are single plain tiles and measure no thicker than 14mm. Ensure the roof opening dimensions and window size match the FK08 2000 Pro+ specification. Check that the roof structure is sound and that the opening is square and level. Have all components to hand and review the Velux installation instructions thoroughly. Ensure you have appropriate roof access equipment and safety measures in place before beginning work.

• Verify tile type and thickness (single plain tiles, up to 14mm)
• Confirm window model compatibility
• Check roof opening dimensions and level
• Inspect roof structure for soundness
• Review Velux installation instructions in full