Fixing and buying guide

Who this product is for

This flashing is intended for builders and contractors working on timber frame construction projects where reliable weather protection is essential. It suits smaller buildings, extensions, and installations where space is limited. Serious DIY users undertaking timber frame work will also find this product suitable for protecting building envelope junctions.

Compatibility and sizing

This flashing is designed for timber frames up to 120mm thick and must be installed on the exterior of the building envelope. The 78×118cm size is compact and ideal for restricted spaces and smaller buildings. Before ordering, confirm that your timber frame thickness does not exceed 120mm and that the flashing dimensions suit your opening or joint size. Check that the opening or vent you are sealing falls within these dimensions to ensure proper coverage and weather protection.

• Maximum timber frame thickness: 120mm
• Flashing dimensions: 78 × 118cm
• Installation location: Exterior of building envelope
• Material: Zinc-coated steel, Grade B24 exterior specification

What is included and pre-installation checks

You will receive one Twin and Combination Flashing unit. Before installation, inspect the flashing for any damage to the zinc coating or structural defects. Ensure the building envelope opening or joint is clean, dry, and free from debris. Verify that the surrounding timber frame is sound and that the frame thickness matches the product specification. Check weather conditions—install in dry conditions to ensure proper sealing and adhesion of any sealants used alongside the flashing.

• Inspect zinc coating for damage or corrosion before use
• Clean and dry the installation area thoroughly
• Confirm timber frame thickness is within specification
• Install in dry weather conditions for best results

Installation and fixing

The flashing must be positioned on the exterior of the building envelope to create a durable, weather-resistant junction around your opening or vent. Secure the flashing according to standard building practice for your specific application—typically using corrosion-resistant fasteners appropriate for zinc-coated steel. Ensure the flashing overlaps adjoining materials correctly to direct water away from the building. Seal all joints and edges with appropriate exterior-grade sealant to maintain watertightness and prevent wind-driven rain penetration. Follow local building regulations and manufacturer guidance for your specific installation type.