Lead-Free Flexible Chimney & Wall Flashing Roll – Self-Adhesive, BBA-Certified

When a chimney starts weeping water into the loft after a storm, the usual culprit is failed lead flashing — cracked from decades of thermal movement, or simply stolen from the roof edge in the night. This flexible, self-adhesive flashing gives roofers and confident DIYers a lead-free alternative that dresses into the same stepped, valley and abutment details as traditional lead, without the weight, the cost swings of the scrap-metal price, or the theft risk.

The material is a reinforced aluminium mesh bonded through a layer of modified bitumen, so it holds a dressed shape around corners and upstands the way lead does, while resisting UV, frost and thermal cycling over a long service life. It is supplied as a roll and cut to length on site, exactly as lead flashing would be.

Key benefits

• Dresses and holds its shape around chimneys, valleys and abutments like traditional lead
• No scrap value — removes the theft risk that affects lead flashing on accessible roofs
• Non-toxic and recyclable, with no lead run-off into gutters or water butts
• Self-adhesive backing for a straightforward, mechanically-fixed-free installation on suitable substrates
• Available in Black or Grey to suit slate, tile or render finishes

Suitable applications

Stepped and abutment flashing around chimney stacks, valley gutters, cover flashings, roof-to-wall junctions, rooflight and conservatory flashing, and cavity trays in masonry walls. Suitable for sharp corners and detailing that would otherwise need a lead slater's skill to dress.

Specification

Independent BRE wind-tunnel testing on a chimney installation, sealed at the laps, recorded no failure at wind speeds up to 110mph — figures as stated by the manufacturer's published test data, not independently re-verified by us for every installation detail, so always follow the fixing and lap-sealing instructions supplied with the roll.

Installation guidance

Surfaces should be clean, dry and free of loose material before application. Work from the bottom of the detail upwards so laps shed water, dress firmly into corners with a wallpaper-style roller or seam roller to fully bond the self-adhesive backing, and seal cut edges and laps with a compatible flashing sealant. For flat roof abutments where this flashing meets an existing EPDM upstand, our EPDM Aluminium Termination Bar gives a mechanically fixed, weathertight lap between the two materials. On pitched roofs being re-covered at the same time, it pairs naturally with our natural roofing slate and ventilated dry ridge kit for a complete re-roof.

FAQs

Is this a genuine substitute for lead flashing?
Yes — it is designed to be dressed and detailed in the same way as lead, in the same applications, and is BBA-certified for general use as a lead alternative.

Do I need a primer before fitting it?
On most sound, dry masonry and roofing substrates a primer isn't required, but porous or dusty surfaces will bond better if primed first — check your substrate before fitting.

Can it be used on both flat and pitched roofs?
Yes. It is equally suited to chimney and valley detailing on pitched roofs and to wall abutments and upstands on flat roofs.

Which width do I need?
As a guide, size the roll so it covers at least 150mm onto the roof covering and 100–150mm up the abutment or chimney face, plus any additional width needed to dress into a stepped detail — measure your specific detail before ordering.

Will it fade or become brittle in UV?
The bitumen-mesh construction is designed for long-term outdoor exposure, with a manufacturer-stated 30-year life expectancy under normal UK weather conditions.

Ordering

Choose your width based on the detail you're flashing and your preferred roll length (6m or 12m, availability varies by width). Order enough width to allow for waste at joints and corners.