Everflex VBS is a two-part, water-based epoxy primer and moisture-vapour barrier for concrete, screeds and suitable masonry substrates. It helps prepare slabs and other mineral surfaces for compatible waterproofing membranes, flooring adhesives and coatings where residual substrate moisture could compromise the finish.
VBS has two distinct jobs. Applied as a primer, it prepares the surface for the next compatible layer. Applied as a specified multi-coat barrier system, it forms a continuous low-permeability film to help control water vapour and moisture pressure. Barrier performance depends on achieving the required dry film build and a pinhole-free finish; a single routine primer coat should not be treated as a complete vapour barrier.
Mix Part A and Part B thoroughly at the specified 1:1 ratio and work within the pot life. Surfaces must be sound and free from standing water, curing compounds and contamination. The required number of coats, coverage and recoat timing differ between priming and vapour-barrier use, so plan the complete coating system before application.
VBS is not an exposed, UV-stable final waterproofing finish. It requires a compatible subsequent membrane, coating or flooring system, and is not intended for application over flowing or standing water. Do not apply it to untested metallic substrates.
What is Everflex VBS used for?
It is a two-part epoxy primer and negative-side moisture barrier for damp or green mineral substrates.
What hydrostatic pressure can it resist?
Up to 250kPa, equivalent to about 25m head of water, at the specified film build.
What dry film thickness is required for the rated barrier?
At least 300 microns.
What is the pot life?
About 2 hours at 25°C.
| Property | Value |
|---|---|
| Product Type | Water Based Epoxy |
| Mixing Ratio | 1:1 by weight or volume |
| Pot Life | 2 hours @ 25°C, 1 hour @ 35°C |
| Consistency | Brush-able/Rollable liquid |
| Recoat Time | 4-24 hours |
| Full Cure | 5-7 days @ 25°C and 50% RH |
| Application Temperature | 10°C to 35°C |
| Storage Temperature Range | 5°C to 35°C |
| Water Vapour Transmission | 0.12 g/24hrs/m²mmhg @ 32°C and 50% RH |
| Coverage Rate | 3-8 m²/litre per coat depending on application |
| Consumption (Primer) | 6 m²/litre for 300 microns dry film thickness |
| Consumption (Vapour Barrier) | 5 m²/litre per coat for 2 coats minimum 200 microns dry film thickness per coat |
| Hydrostatic Pressure Resistance | Up to 25 metres (250 kPa) head of water @ 300 microns dry film thickness |
| Shelf Life | 2 years |
| Clean Up | Water |
| VOC Content | <5 g/l |
| Storage Conditions | 5°C and 35°C |
| Water Resistance | Can withstand up to 25 metres head of water when applied at the recommended coverage rate with a minimum dry film thickness of 300 microns. |
Here are some common examples on where Everflex VBS Water-based Epoxy Primer used by our customers.
