ClassicBond EPDM Water Based Deck Adhesive for Rubber Roofing

ClassicBond Water Based Adhesive is used to bond ClassicBond EPDM rubber roofing to:

• Timber roof decks (OSB3 or plywood)
• The main field area of flat roofs
• Residential flat roofs, garages, porches, garden rooms and extensions

On timber decks, it is typically used:

• Across the main roof area
• With ClassicBond Contact Adhesive used separately at edges, upstands and details

This combination provides a secure, compliant EPDM installation.

Water-based adhesive is the preferred choice for flat timber decks because it offers:

• Low odour and non-flammable application
• A longer working time for positioning the membrane
• Controlled bonding over large areas
• Strength that develops over time
• A safer, more comfortable installation - Easier for DIY, Faster for trade

ClassicBond Water Based Adhesive is suitable for bonding EPDM rubber roofing to:

• OSB3 boards
• Plywood (Structural Grade)

All boards must:

• Be clean, dry and sound
• Be free from waxes, sealers or non-absorbent coatings

Not suitable for non-porous surfaces such as:

• Metal
• Existing GRP
• Sealed or low-vapour-permeable decks

For these surfaces, ClassicBond Contact Adhesive should be used as the deck adhesive instead.

EPDM should never be bonded directly to felt or other bituminous substrates.

• Apply using a medium-pile roller
• Spread evenly at approx. 3–4 m² per litre
• Lay the EPDM membrane into the wet adhesive
• After applying the adhesive, you have roughly 5–15 minutes to lay the membrane into it, depending on temperature and weather conditions
• Press and consolidate with a broom or roller to ensure full transfer

The adhesive must not be used below 4°C, or if temperatures are expected to fall below this during curing

• Stir thoroughly before use
• Apply to one surface only (deck)
• Ensure full adhesive transfer to the membrane

Approximate coverage:

• 1.0L – covers approx. 3–4 m²
• 2.5L – covers approx. 7–10 m²
• 5.0L – covers approx. 15–20 m²
• 10L – covers approx. 35–40 m²
• 15L – covers approx. 50–60 m²

Coverage may vary depending on surface texture and porosity.

For roofs over 100 m², ClassicBond Contact Adhesive should be used as the deck adhesive instead of water-based adhesive.

• Product: ClassicBond EPDM Water Based Adhesive (WBA)
• Type: Acrylic resin, non-flammable
• Colour: Cream
• Coverage: Approx. 3–4 m² per litre
• Tack / open time: Approx. 5–30 minutes
• Shelf life: 12 months (stored between 5°C and 30°C)
• Application: One-sided, wet-lay deck adhesive

Water-based adhesive is what makes large EPDM roofs easier to install. It gives you working time to position the sheet, work cleanly, and achieve a smooth finish without fighting solvents or fumes.

Used on the main deck area - with contact adhesive at the edges - it’s the simplest and most reliable way to install EPDM rubber roofing on timber roofs.