Description

Owl PU Mastic is an industrial-strength polyurethane adhesive and sealer, engineered for fast-curing performance in demanding waterproofing and construction applications. Whether you’re filling gaps, smoothing joints, or sealing cracks, PU Mastic delivers reliable, long-lasting results on almost any surface — making it one of the most versatile products in the Owl Waterproofing range.

What Makes Owl PU Mastic Different

Unlike standard fillers or sealants that shrink, crack, or lose adhesion over time, Owl PU Mastic is formulated as a true polyurethane adhesive sealer. This means it bonds aggressively to a wide range of substrates — concrete, masonry, timber, metal, and most common building materials — while remaining flexible enough to handle natural movement in joints and surfaces without failing.

Its fast-curing formula means you’re not left waiting around for a workable finish. Once applied, PU Mastic sets quickly, allowing you to move on to the next stage of a repair or waterproofing job without unnecessary downtime — a key advantage on time-sensitive commercial and residential projects alike.

Key Features & Benefits

Fast-curing polyurethane formula — reduces project downtime and speeds up repair turnaround
Strong adhesion sealer — bonds firmly to concrete, masonry, timber, metal, and most porous and non-porous surfaces
Fills and smooths gaps, holes, and joints — ideal for sealing cracks before they become bigger structural or waterproofing issues
Flexible, crack-resistant finish — accommodates minor surface movement without losing its seal
Suitable for emergency repairs — can be used as a standalone fix when a fast, dependable seal is needed
Compatible with the full Owl Lava 20 Waterproofing System — integrates seamlessly as part of a complete, warrantied waterproofing solution

Where to Use Owl PU Mastic

PU Mastic is suited to a wide range of applications, including:

Sealing joints and gaps in roofing, balconies, and terraces before waterproofing
Filling cracks in concrete, render, or masonry ahead of a Lava 20 application
Emergency repairs where a fast, strong seal is needed to prevent water ingress
General construction sealing tasks requiring an adhesive that won’t shrink or degrade over time
Detail work around penetrations, upstands, and awkward joints where precision sealing matters

Because it adheres to almost any surface, PU Mastic is equally useful for professional contractors managing large waterproofing projects and for property owners tackling a one-off emergency repair.

Part of the Owl Lava 20 Waterproofing System

While Owl PU Mastic performs well as a standalone product, it’s also designed to work within the broader Owl Lava 20 Waterproofing System — a high-performance polyurethane liquid rubber system backed by a 25-year warranty. Used together with products like Lava Detail 20 and Lava 20 Vertical, PU Mastic helps create a fully sealed, joint-free foundation before the main waterproofing coat is applied — closing off the small gaps and cracks that could otherwise become long-term points of failure.

This makes PU Mastic more than just a standalone sealant: it’s a preparatory step that strengthens the overall performance and durability of the finished waterproofing system, helping every subsequent layer perform as intended.

A Dependable Choice for Every Job

Whether you’re a contractor sourcing a dependable polyurethane adhesive sealer for a full waterproofing project, or a homeowner facing an urgent crack or leak that needs immediate attention, Owl PU Mastic offers the fast-curing strength and flexibility to get the job done right the first time. Backed by the same quality standards as the rest of the Owl Waterproofing range, it’s a small product that plays a big role in protecting your structure for years to come.