Fixing and buying guide

What this product is and who needs it

An insulation collar is an essential flashing accessory that sits between your VELUX roof window and the surrounding roof material. It prevents water ingress, reduces thermal bridging, and creates a finished appearance around the window opening. You need this product if you are installing a VELUX FK06 roof window or compatible Sun Tunnel system and want a professional, weather-tight result that meets building standards.

Compatibility and sizing

This collar is engineered specifically for VELUX FK06 roof windows and compatible VELUX systems. The dimensions are 660 × 1180 mm, which corresponds to the FK06 window size. Before ordering, confirm that your roof window is an FK06 model. Using the correct size collar ensures proper fit, effective weather sealing, and optimal thermal performance. Mismatched sizes will compromise the installation.

• Compatible with VELUX FK06 roof windows
• Compatible with VELUX Sun Tunnel systems (FK06 size)
• Dimensions: 660 × 1180 mm
• Check your window model before purchase

Installation and preparation

The insulation collar is designed for straightforward installation as part of the VELUX roof window system. It should be fitted during the window installation process, positioned between the window frame and the roof opening. Ensure the roof opening is clean and free from debris before fitting. The collar works in conjunction with other VELUX flashing components to create a complete weather-tight seal. Follow VELUX installation guidance for your specific roof type and pitch.

• Install during roof window fitting
• Position between window frame and roof structure
• Clean roof opening before installation
• Use with compatible VELUX flashing components
• Suitable for new build and refurbishment work

Performance and conditions

This collar is engineered to perform reliably in typical UK roof conditions, providing durable weather protection and thermal insulation over the service life of your roof window. It contributes to an integrated daylight and ventilation solution for your property, helping to maintain comfort and energy efficiency whilst keeping the roof weather-tight.