Fixing and buying guide

What this product is and who it is for

This is a coupled flashing kit designed specifically for VELUX roof windows and Sun Tunnel systems on slate roofs. It is for builders, roofers, and serious DIY customers installing or upgrading roof windows where a weather-tight, professional finish is essential. The recessed 8mm design means the flashing sits flush with slate, avoiding the raised appearance of standard flashings and maintaining visual consistency across your roof.

Compatibility and sizing

This flashing is sized at 940 x 1600mm (94 x 160cm) and is compatible with VELUX roof window and Sun Tunnel systems. Before ordering, confirm your roof window model and opening dimensions match this flashing size. The EKN PK10 S0021E is specifically engineered for slate roof integration, so it is not suitable for other roof coverings such as tiles or felt.

• Check your VELUX roof window or Sun Tunnel model number against the product code EKN PK10 S0021E
• Verify your roof opening dimensions are 940 x 1600mm
• Confirm your roof covering is slate before purchasing

Pack contents and pre-installation checks

This is a twin and combination flashing unit, meaning it accommodates multiple roof windows or a combination of window and Sun Tunnel installations. Inspect the flashing on delivery for any damage to the material or sealing edges. Check that all components are present and undamaged before beginning installation. Ensure your roof structure is sound and that the opening is correctly sized and prepared to receive the flashing.

• Unpack and visually inspect the flashing for damage
• Verify the opening dimensions match 940 x 1600mm
• Check that the roof structure around the opening is sound and level
• Ensure slate tiles around the opening are in good condition

Installation and weather-tightness

The recessed 8mm design requires careful integration with your slate roof to achieve a weather-tight seal. The flashing must be positioned so that the recess sits flush with the slate surface, and all edges must be sealed according to VELUX installation guidance. Proper installation is critical to prevent water ingress and ensure the flashing performs reliably in UK weather conditions. If you are not experienced in roof work, we recommend engaging a qualified roofer to carry out the installation.