Fixing and buying guide
VELUX Underfelt Collar 114x118cm BFX SK06 1000
What this product is and who it is for
The underfelt collar is an essential component for installing VELUX SK06 skylights into pitched roofs. It sits between the skylight frame and the roof structure, providing a durable felted seal that prevents water penetration around the installation perimeter. This product is for builders, roofers, and serious DIY customers installing new skylights or replacing existing units in timber-framed roofs.
- Designed specifically for VELUX SK06 skylight models
- Prevents water ingress at the skylight-to-roof junction
- Suitable for residential and commercial applications
- Essential component for weather-tight installation
Compatibility and sizing
This collar measures 114x118cm and is engineered to fit VELUX SK06 skylights. It is compatible with timber roof grades F16 and F24, which are standard structural timber grades used in UK roofing construction. Before ordering, confirm your skylight model is SK06 and verify your roof timber grade specification. The collar dimensions are designed to provide adequate coverage around the skylight frame for a secure seal.
- Size: 114x118cm
- Compatible with VELUX SK06 skylights only
- Works with timber grades F16 and F24
- Check your roof specification before purchase
Installation and preparation
The underfelt collar features straightforward installation. Position it around the skylight frame opening before securing the skylight to the roof structure. The durable felted construction compresses slightly under the skylight weight, creating a weather-tight seal. Ensure the roof opening is cut to the correct size for the SK06 model and that the surrounding timber is sound and properly supported. The collar should sit flat without wrinkles or folds to maintain its sealing effectiveness.
- Install collar around skylight frame before final fixing
- Felted material compresses to form weather-tight seal
- Ensure roof opening matches SK06 specifications
- Check timber is sound and properly supported
Pre-installation checks
Before fitting, verify that your skylight model is VELUX SK06 and that your roof structure uses F16 or F24 timber grades. Inspect the collar for any damage during delivery. Confirm the roof opening dimensions are correct for the SK06 model and that the surrounding roof structure is level and properly prepared. Have all necessary roofing materials and flashing components ready before beginning installation to ensure a continuous, weather-tight finish.
- Confirm skylight model is SK06
- Check timber grade is F16 or F24
- Inspect collar for transport damage
- Verify roof opening size and structural readiness