Fixing and buying guide

What this product is for

This insulation collar provides the critical seal around your VELUX roof window frame where it meets the building structure. It stops draughts and water penetration at this vulnerable junction, which is especially important in timber-framed construction where gaps between frame and wall can significantly affect heating efficiency and building durability. Without a proper collar, warm air escapes and moisture can enter, leading to heat loss and potential timber damage.

Compatibility and sizing

This collar is sized 55 x 118cm and is specifically designed for VELUX roof windows in the CK06 2011 specification. Before ordering, confirm your VELUX window model matches this specification. The collar dimensions must align with your window frame size and the opening in your roof structure. Check your VELUX documentation or measure your existing window frame to ensure correct fit.

• Size: 55 x 118cm timber collar
• Grade: BDX CK06 2011
• Designed for VELUX roof windows only
• Suitable for timber-framed buildings
• Verify your window model before purchase

Installation and preparation

The collar is installed during roof window fitting, positioned between the window frame and the surrounding wall structure. Ensure the roof opening is correctly sized and the timber framing is sound and level before installation. The collar must sit flush against both the window frame and the wall to create an effective seal. Proper installation is essential for the collar to perform its draught-proofing and weatherproofing function.

• Install between window frame and wall structure
• Ensure roof opening is correctly dimensioned
• Check timber framing is level and in good condition
• Position collar to create tight seal on all sides
• Follow VELUX installation instructions for your specific window model

Pre-installation checks

Before fitting, inspect the collar for any damage to the timber. Verify that your roof structure opening matches the collar dimensions and that the surrounding timber framing is dry, level, and structurally sound. Confirm you have the correct VELUX window model for this collar specification. Check that all necessary fixings and sealing materials are available before beginning installation work.