How to use damp-proof membranes for floors

Weber UK

Learn how to use damp-proof membranes to prevent damp from working its way into your floors. 

Damp-proof membranes protect building structures against damp. Whether it’s penetrating damp, residual construction moisture or — in rare instances — rising damp, it’s important that the underlying issues are addressed and fixed before any refurbishment or redecoration is carried out. Some areas where a damp-proof membrane is advised include underfloor heating and bathroom floors.

weberfloor DPM offers damp proofing for concrete floors and cement based levelling compounds using an easy two-coat system. An effective liquid damp proof membrane resistant to a wide range of chemicals, it is used for oversealing cementitious surfaces which contain high levels of residual moisture. It also permits early overlaying with vinyl, carpets and resin based products after the addition of a floor screed or levelling compound, and it can be used down to 5°C, allowing work to continue during winter.

Take a look at our quick guide below on the best way to use weberfloor DPM to damp-proof your floors.

1. Prepare substrate

weberfloor DPM can be applied on substrates such as concrete and cement-based levelling compounds. All surfaces must be mechanically sound, dry and clean, i.e. free from dirt, dust, grease or other contamination or coating. Laitance must also be removed from concrete.

2. Mix

Pour the resin into a clean, dry bucket. Add in the hardener and mix at a slow speed using a drill and paddle until a uniformly clear consistency is achieved. Once mixed pour into roller tray to extend pot life.

3. Apply

weberfloor DPM should always be applied in two coats. Immediately after mixing, spread onto the substrate using a brush or roller – make sure coverage is even and consist across the entire substrate.

The second coat should be applied after the first coat has partially cured (approx 6-8 hours). Do not leave the first coat longer than 24 hours before re-coating. Apply the second coat evenly and uniformly at right angles to the first coat to ensure full coverage of the substrate.

Immediately after application of the second coat cover weberfloor DPM with a full scatter of kiln-dried sand, using 1-2mm.

Watch the application of weberfloor DPM in the video below:

After applying

After 12 hours (or overnight), the floor should be brushed and vacuumed to remove any loose sand particles. It should then be primed using weberfloor 4716 primer, then it's ready to receive a levelling compound.

If you are in doubt on whether or not you need to use damp-proof membrane, or you have any questions about using weberfloor DPM, please feel free to get in touch with us.

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