How and where to use guide
VELUX Recessed Flashings 78x98cm EDN MK04 0000
Suitable applications and roof types
This recessed flashing is designed for installation into roof eaves around roof penetrations. It performs effectively on both pitched roofs and flat roof applications, making it versatile for most UK residential and commercial roofing projects. Common installations include sealing around VELUX skylights, chimney stacks, roof vents, soil pipes and other services that pass through the roof plane. The flashing sits recessed into the eaves, providing a neat finish whilst maintaining a weather-tight seal.
- Pitched roof installations
- Flat roof applications
- Skylight installations
- Chimney flashings
- Roof vent sealing
- Soil pipe and service penetrations
Timber grade requirements and structural considerations
This flashing is only suitable for use with timber grades F16 or above. F16 timber has a minimum bending strength of 16 N/mm² and is the standard structural grade for most UK roof construction. Before installation, verify that your roof timbers meet this minimum specification. Weaker timber grades will not provide adequate support for the flashing system and may lead to structural failure or water ingress. If your roof structure uses lower grade timber, you must upgrade the supporting timbers or seek structural advice before proceeding.
- Minimum timber grade F16 required
- Check existing roof timbers before installation
- Do not install on lower grade timber
- Upgrade timbers if necessary to meet specification
Installation and weather protection
The flashing must be installed into the roof eaves to create a recessed, weather-tight seal. Proper installation is critical to prevent wind-driven rain and snow from penetrating around the roof penetration. The corrosion-resistant material and durable finish are designed to withstand prolonged exposure to UK weather, but installation must be completed before the roof is exposed to heavy rain or snow. Ensure all edges are properly sealed and that the flashing sits flush with the surrounding roof surface to prevent water pooling or deflection.
- Install into roof eaves during dry weather conditions
- Ensure complete weather-tight seal around all edges
- Check for proper fit and flush installation
- Avoid water pooling or gaps around the flashing perimeter
Maintenance and durability
The corrosion-resistant finish provides long-term protection against rust and weathering in UK conditions. Periodically inspect the flashing, particularly after severe weather, to ensure the seal remains intact and there are no signs of water ingress around the penetration. Clear any debris, moss or lichen growth from the flashing surface to maintain water run-off and prevent staining. The durable material requires minimal maintenance, but prompt attention to any damage or seal deterioration will extend the life of the installation and protect the roof structure beneath.
- Inspect regularly for damage or seal deterioration
- Clear debris and organic growth from the surface
- Check for water ingress around the penetration
- Address any damage promptly to prevent water damage