3000 Series — Emergency Roof Repair

Belzona 3121

MR7 — Liquid-applied emergency roof repair material providing instant waterproofing of leaking roof areas.

A 2-part polymer composite for instant emergency waterproofing. Bonds to slate, tile, asphalt, felt, metal and asbestos cement — even in rain and sub-zero temperatures. Water resistant immediately after application. Can cure fully immersed in water. No primers or conditioners required.

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Product Description

A 2-part polymer composite designed to provide emergency roof repair and weatherproofing for leaking roof areas. Bonds strongly to all common roofing surfaces including slate, tile, asphalt, felt, asbestos cement and metal roofs, even during adverse weather conditions.

This fast-curing, all-climate flexible repair system incorporates a reinforcement sheet which ensures the coating adapts to roof movements and follows complex roofing contours. Water resistant immediately after application and can cure even if fully immersed in water.

0°C

Min. cure temperature

Instant

Water resistance

Immersed

Cures even underwater

Key Benefits

Can be applied and will cure even during adverse weather conditions
Simple application method — no primers or conditioners required
Application and cure as low as 0°C (32°F)
No hot work involved
Microporous structure allows trapped moisture to escape whilst providing long-term weatherproofing
Excellent adhesion to felt, asphalt, lead, zinc, copper, glass, concrete and brick
Adapts to roof movements with its outstanding elasticity
Can be easily applied by brush

Applications

Emergency repair of roof lights, gutters, splits in roofing felt, leaking joints and other roof areas
Sealing of joints and seams to provide weatherproofing and waterproofing

* All products are subject to regional restrictions.

Frequently Asked Questions

What common problems cause roof leaks that Belzona 3121 (MR7) can fix?

Roof leaks often occur due to aging or damaged roofing materials, failed joints and seams, cracked flashing, or weather-related wear and tear. These allow water to penetrate the roof, leading to internal damage and urgent repair needs.

How does Belzona 3121 (MR7) address these roofing problems?

Belzona 3121 (MR7) is a liquid-applied, two-part polymer composite designed for emergency roof repair and weatherproofing. It bonds strongly to a wide range of roofing surfaces — including slate, tile, asphalt, felt, asbestos cement, and metal — even in adverse weather. Its fast-curing, flexible system incorporates a reinforcement sheet, adapting to roof movements and provides instant waterproofing, even if applied in rain or on wet surfaces.

What makes Belzona 3121 (MR7) effective for urgent roof leak repairs?

It can be applied and cures in wet or cold weather, providing immediate water resistance. Requires no primers or conditioners and is applied easily by brush. Forms a seamless, flexible membrane that adapts to roof movement. Bonds to most common roofing materials — suitable for sealing leaks, joints, seams, gutters and cracks.