Fixing and buying guide

Who this product is for

This flashing is essential for anyone installing a VELUX skylight into a pitched timber roof. It suits both professional roofing contractors and experienced DIY installers who are confident working at height and with roof structures. You will need this flashing to complete a watertight installation and meet building regulations for weather protection.

Compatibility and sizing

The 134x140cm size is designed to accommodate most standard VELUX skylight installations. Before ordering, confirm that your roof timber is graded F16, F24 or F36 — these are the only compatible grades. Check your skylight model number against VELUX documentation to ensure this flashing is the correct match. The flashing is engineered to work around common roof obstructions including vents, chimneys and other penetrations, but measure your specific installation to confirm adequate coverage.

• Dimensions: 134 x 140cm
• Compatible timber grades: F16, F24, F36 only
• Verify VELUX skylight model compatibility before purchase
• Suitable for roofs with nearby vents and chimneys

What is included and pre-installation checks

This is a complete flashing kit combining aluminium frame and rubber seal components ready for installation. Before fitting, inspect all components for damage in transit. Ensure the roof opening is cut to the correct size and that the surrounding timber structure is sound, dry and free from rot. Check that the roof pitch and timber grades match the product specification. Have all necessary roofing tools and sealants to hand before beginning work, as the installation must be completed in dry conditions to achieve a proper watertight seal.

• Inspect flashing components for transport damage
• Verify roof opening dimensions match flashing size
• Check timber is sound, dry and correct grade
• Plan installation for dry weather conditions
• Gather roofing tools and compatible sealants before starting

Installation overview

The flashing must be fitted during skylight installation to create the watertight seal between the skylight frame and the roof surface. Position the flashing carefully around the skylight perimeter, ensuring the rubber seal components make full contact with both the skylight frame and the roof structure. The aluminium components should be secured according to VELUX instructions, and all joints must be sealed to prevent water ingress. This is a critical weatherproofing step — poor installation will result in leaks. If you are uncertain about any aspect of the fitting process, consult VELUX installation documentation or engage a qualified roofer.