Bostik MOISTURE SEAL
Bostik Moisture Seal is a two-part, water-based epoxy moisture and vapour barrier designed for application over concrete substrates. It effectively prevents the transmission of moisture vapour through concrete slabs and is suitable for both newly laid (green) and cured concrete. This system provides a reliable barrier against rising damp and water seepage, while also enhancing adhesion for subsequent layers. Its low-odour, solvent-free formula makes it ideal for interior applications where user and occupant safety is a concern.
Once cured, Bostik Moisture Seal forms a tough, water-resistant film with excellent bond strength to concrete and masonry. It also acts as a high-performance primer under a variety of flooring systems, including timber, vinyl, tiles, carpets, and resilient floor coverings.
Recommended Uses
As a water vapour barrier in residential, commercial, and industrial construction
As a primer and moisture barrier prior to:
Installation of timber and engineered wood flooring
Application of resilient flooring such as vinyl, carpet tiles, and rubber
Laying of ceramic or stone tiles
Underlay for Bostik cementitious levelling compounds, screeds, and mortars
Compatible primer for Bostik Ultraset® flooring adhesives and Dampfix® waterproofing membranes
Moisture barrier over freshly poured (green) concrete with moisture contents up to 95% RH
Prevents debonding or blistering of adhesives due to moisture vapour transmission
Key Features & Benefits
Two-part water-based epoxy – easy to mix and apply
Excellent adhesion to concrete and masonry
Suitable for use on green concrete
Non-flammable, low odour and VOC compliant
Compatible with most Bostik flooring adhesives and waterproofing membranes
Fast recoat time and short cure window – allows for quicker project turnaround
Moisture vapour resistance up to 95% RH (ASTM F2170) or 5.5% moisture content (Tramex method)
Packaging
Available as a 2-part kit (Part A & Part B) in:
4L kit (suitable for approximately 20–25m² coverage depending on substrate porosity)