Fixing and buying guide

Who this product is for

This recessed flashing is suitable for both professional roofers and experienced DIY installers undertaking skylight installation or replacement work. It is intended for customers installing or maintaining VELUX EDJ CK04 2000 skylight units in pitched roof applications where roof valleys are present. You should be confident working at height and familiar with roof construction before attempting installation.

Compatibility and sizing

This flashing is designed specifically for VELUX EDJ CK04 2000 skylight units and must not be used with other skylight models. The 55×98cm dimensions are engineered to suit standard pitched roof installations. Timber grade compatibility is F16 and above; check your roof structure meets this specification before purchase. Confirm your skylight model matches EDJ CK04 2000 exactly, as using incorrect flashings will compromise weatherproofing.

• Compatible only with VELUX EDJ CK04 2000 skylights
• Requires timber grades F16 or above
• Dimensions: 55×98cm (21.6×38.6 inches)
• Designed for roof valley and pitched roof applications

Pre-installation checks

Before fitting, verify that your roof structure is sound and that the timber grades meet F16 specification or above. Inspect the roof valley and surrounding area for any existing damage, rot, or structural issues that must be remedied before flashing installation. Ensure the skylight unit is correctly positioned and ready for flashing integration. Check that all components of your skylight kit are present and undamaged.

• Confirm timber grades F16 or above in roof structure
• Inspect roof valley for damage or deterioration
• Verify skylight unit is correctly positioned
• Check all skylight components are present before starting

Installation and weatherproofing

Installation is required to ensure this flashing performs its intended function of creating a watertight seal. The flashing must be fitted precisely to eliminate gaps between the skylight and roof valley, as poor installation will result in water ingress and potential structural damage. Follow VELUX installation guidance carefully, ensuring the flashing is secured and sealed according to manufacturer instructions. Professional installation is recommended if you are uncertain about the process.

• Installation is essential for weatherproofing performance
• Precise fitting required to eliminate water ingress pathways
• Follow VELUX installation instructions carefully
• Consider professional installation if you lack roof experience