Fixing and buying guide

Who this product is for

This underfelt collar is intended for builders, roofers, and serious DIY customers installing or renovating timber frame roofs. It is essential for anyone constructing or repairing pitched roofs with timber frame construction where weather protection and air-tightness are priorities.

Sizing and compatibility

The 78cm x 98cm dimensions are designed to fit standard timber frame roof applications. Before ordering, measure your timber frame end to confirm it falls within these standard dimensions. This collar is specifically engineered for timber frame construction and should not be used with other roof frame types. Verify that your roof pitch and frame configuration are compatible with a standard collar installation.

• Dimensions: 78cm length x 98cm width
• Suitable for standard timber frame roof construction
• Check your frame dimensions match before purchase

What is included and material

Each pack contains one underfelt collar manufactured from felted underfelt material with a smooth finish. The BFX MK04 1000 grade is specified for durability and long-term weather resistance in exposed roof conditions.

• Material: Felted underfelt with smooth finish
• Grade: BFX MK04 1000
• Quantity: One collar per pack

Pre-installation checks and fixing

Before installation, inspect the timber frame end for damage, rot, or irregularities that could prevent a weather-tight seal. Ensure the frame surface is clean and dry. The collar is designed for straightforward installation over the timber frame end. Position it carefully to achieve a snug fit across the entire frame junction, ensuring no gaps remain where moisture or air could penetrate. Secure according to roof construction best practice and local building regulations.

• Check timber frame for damage or rot before fitting
• Ensure frame surface is clean and dry
• Position collar for snug fit with no gaps
• Secure appropriately to prevent wind lift and maintain weather seal