Flashing & Seam Tapes for EPDM Roofs

EPDM Flashing Tapes & Seam Tapes — Professional Waterproofing Details

Our EPDM flashing tapes and seam tapes are essential products for creating fully watertight details at roof edges, upstands, penetrations and overlapping joints. Used by professional roofers across the UK, these products are specifically designed for use with EPDM rubber membranes.

Types of Flashing & Seam Tape Available

Uncured EPDM Flashing Tape — The most widely used flashing product for EPDM roofing. Self-adhesive, with butyl backing. Used for all upstand and corner details, pipe penetrations, drain collars and perimeter detailing. Bonds directly to both EPDM membranes and most substrates. Available in 75mm and 150mm widths.

EPDM Corner Patches — Pre-formed uncured EPDM patches for internal and external corners. Provides a consistent, watertight corner detail every time without the need for site-cut mitred joints.

Lap Tape — Self-adhesive tape used to seal the lap joint where two lengths of EPDM membrane overlap. Provides an additional weather seal over the bonded lap.

Seam Cover Strip — For covering and sealing exposed edge trims and termination bar fixings.

Formflash — A flexible flashing membrane made from EPDM/PIB blend. Ideal for awkward or irregular shapes where a more pliable material is needed. Self-adhesive, moulds to complex profiles.

Lineflex Flashing Tape — UPVC-backed self-adhesive flashing tape. Ideal for interfaces between EPDM membranes and brickwork, fascias and metal cappings.

When Do I Need Flashing Tape?

Flashing tape is required at every detail in an EPDM roof installation, including upstands at walls and parapets, pipe and cable penetrations, drain outlets, corner angles and any point where the membrane terminates at a vertical surface.

Properly installed flashing is what separates a watertight roof from one that leaks. We recommend using manufacturer-approved flashing products matched to your membrane system.

Frequently Asked Questions

What width flashing tape do I need? 75mm tape is suitable for most upstand and corner applications. Use 150mm tape on larger upstands, walls and anywhere greater coverage is needed.

Can I use flashing tape on a wet surface? No. All surfaces must be clean, dry and free of contamination before flashing tape is applied. Use our EPDM Primer on borderline surfaces for improved adhesion.

How do I seal around a roof outlet? Use a purpose-made drain outlet collar bonded to the membrane with contact adhesive, then lap the membrane over the collar flange and seal with uncured flashing tape around the perimeter of the collar.

Do I need primer before applying flashing tape? On clean, new EPDM membrane, primer is not always required. On older, weathered EPDM or on smooth non-EPDM surfaces, always apply primer first for a reliable bond. When in doubt, prime.

Need advice on your specific detail? Call our technical team on 02031510153 — we can talk you through the right product and application method for any situation.