Watco New Concrete Primer is a two pack, virtually solvent free, epoxy resin liquid damp-proofer. This one coat application suppresses residual moisture in new concrete, allowing the floor to be coated and put into use quickly without waiting for the concrete to dry out.

Most coatings cannot normally be applied until the new concrete moisture content has reduced to less than 75% RH (relative humidity), which can take several weeks or months depending on the depth of the concrete.

New Concrete Primer will tolerate up to 98% RH.

Watco New Concrete Primer can be overcoated with most types of floor paint after approximately 16 hours. The special formulation encourages penetration and good adhesion, and the flow control agents help resist air pinholes forming, essential in a damp proofing coating.

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• Features & Benefits
• Surface Preparation
• Mixing
• Application
• Standard Compliance
• Limitations

Features & Benefits

• For newly laid concrete, sand & cement screed, and suitable for areas subject to heavy traffic
• Suppresses construction moisture which enables newly laid concrete floors to be painted and put into use quickly
• Virtually solvent free, epoxy resin liquid moisture barrier
• Withstands up to 98% RH (relative humidity)
• Ready for over coating in 16 hours
• Suitable for heavy wear areas
• Flexible
• Can be used with underfloor heating systems

Surface Preparation

Concrete & sand and cement screed – should be sound, clean and free of any contaminants liable to prevent penetration into the substrate or adhesion to the surface. Machine scarifying or shot blasting are ideal ways to clean and prepare large areas of concrete and remove contaminants. Use a vacuum to remove all surface dust.

Very smooth or power floated concrete – should be shot blasted to provide a good key for the New Concrete Primer to bond to. Use a vacuum to remove all surface dust.

Underfloor heating systems – should be switched off at least two days prior to the application of New Concrete Primer and left for a minimum of two days before switching back on. Once switched on, the underfloor heating should gradually be turned up a few degrees at a time.

Mixing

The product comprises a resin and curing agent packed in a plastic container. Remove the lid from the container and remove the ‘top chamber’ which contains the curing agent. Tip the contents of the top chamber into the container, mixing with the resin.

Mix thoroughly using a wide bladed tool – a piece of batten is ideal. Scrape around the sides and bottom of the container to ensure the product is well mixed. This is fine for a small number of units. If you have multiple packs to mix we recommend a paint stirrer in a slow speed electric drill.

Application

Important – once the contents of the pack have been mixed, a chemical reaction takes place which creates heat, and the product should therefore be decanted into a roller tray and used immediately.

Best results are obtained in warm (minimum of 15°C), dry conditions with good ventilation. Apply with a medium pile roller, (not foam), working well in the surface of the concrete. One thick (250 microns) coat is usually sufficient. The coating should cover the substrate leaving no pin holes or missed patches. Most reasonable quality new concrete will cover successfully with one coat. Inspect the surface once the first coat has dried. Apply a second coat to cover any patches which may have been missed or where trapped air has caused pinholes. The product contains special wetting agents which help prevent air bubbles forming on most concrete surfaces.

Repairs/Resurfacing – If the intention is to apply a floor screed or resurfacer, such as Watco Flowtop, or Concrex to the New Concrete Primer, then 2 coats are required. Please blind the second coat with dry sand to provide a key for the overlay material.

Standard Compliance

• BREEAM Compliant
• Very low VOC level (10g/litre)
• ISO 16000
• REACH Compliant

Limitations

If the surface to be primed is very porous or open textured, trapped surface air may cause pinholes. The first coat should be inspected on such surfaces and a second coat applied in any patches where pinhole air holes exist.

Do not exceed the coverage stated – mark out an area of 25m² per pack to avoid applying it too thinly.

Once mixed, use immediately, and finish within 1 hour. Do not part mix. Only mix enough packs that can be used within the working life.