Flexitec Single-Ply (SP) Primer 1 Litre

Single-Ply Primer for Flexitec 2020 GRP Roofing Systems

Flexitec SP Primer is a single-component, moisture-curing primer designed for use when installing the Flexitec 2020 GRP roofing system over existing single-ply membranes.

It is used following adhesion testing to prepare compatible single-ply substrates, allowing Flexitec resin to bond correctly and perform as intended.

When Flexitec SP Primer Is Required

Flexitec SP Primer is required when Flexitec 2020 resin is being applied over certain single-ply roofing membranes, including:

• EPDM
• TPO
• Other compatible single-ply membranes (subject to adhesion testing)

It is not a general-purpose primer and should only be used where adhesion tests confirm suitability, in accordance with the Flexitec application manual.

Why Flexitec SP Primer Is Used on Single-Ply Membranes

Single-ply membranes behave very differently to mineral or bituminous substrates. Flexitec SP Primer is formulated to:

• Promote reliable adhesion to suitable single-ply surfaces
• Provide a stable bonding interface for Flexitec resin
• Enable controlled refurbishment and overlay installations
• Reduce risk when coating aged or weathered membranes

Used correctly, it makes approved single-ply overlays predictable, compliant and system-safe.

Application Overview

Flexitec SP Primer is quick and straightforward to apply:

• Single-component (no powder hardener required)
• Moisture-curing
• Applied by brush or roller
• Thin, even coat only, avoid excess build-up
• Typical cure time: 2–4 hours, depending on conditions

The Flexitec system should be applied on the same day once the primer has cured, to maximise adhesion.

Coverage Rates

• Approx. 12–15 m² per litre
• Coverage varies depending on membrane type and surface condition

Ensure the surface is clean, dry and properly prepared before application.

Product Details

• Product: Flexitec SP Primer
• Pack size: 1 litre
• Type: Single-component, moisture-curing primer
• Application: Brush or roller
• Coverage: Approx. 12–15 m² per litre
• Use: Priming single-ply membranes prior to Flexitec 2020 resin application

Important Notes on Use

• Adhesion tests must be carried out before use
• Not all single-ply membranes are suitable for over-coating
• Apply a thin coat only — do not over-apply
• If more than 7 days elapse before coating, re-priming may be required

A Roofer’s Perspective

Overlaying single-ply roofs isn’t something you guess your way through. Flexitec SP Primer exists to allow approved, controlled overlays onto compatible single-ply membranes where adhesion has been proven.

Used correctly, it allows Flexitec 2020 to be installed with confidence on refurbishment projects that would otherwise require full strip-off.