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Watco Concrex Fine Filler

Fills imperfections in concrete floors prior to painting

  • Virtually indestructible
  • Can be applied inside and out

Frequently bought together


Watco Concrex® Fine Filler is a two pack epoxy resin paste for filling small gaps, cracks and holes in concrete and masonry. It is quick and easy to use, with no odour, and is extremely strong once cured. 

Recommended areas of use

  • Can be used inside or outside
  • Ideal for repairing minor imperfections in floors or vertical surfaces before painting


  • Easy to mix 50:50 ratio by weight or by volume
  • Concrex® strength, will withstand very heavy traffic after curing overnight
  • Resistant to most industrial chemicals (after 4 days to achieve full hardness)

The finished repair can be painted with any Watco coating or it can be left as a wearing surface. Watco Concrex® Fine Filler is economical to use as you mix only as much as you need. It is virtually solvent free and will not shrink as it cures. No primer is necessary and it can be used for repairs with a very fine edge (feather edging). 

For repairs deeper than 5mm we recommend you use Watco Concrex® Original.

Properties Ideal for repairing scratches and blemishes in floors or vertical surfaces, easy to mix 50:50 ratio by weight or by volume, will withstand very heavy traffic, resistant to most chemicals.
Suitable for Concrete, sand and cement, metal.
Interior or Exterior Interior and exterior.
Primer required No primer required.
Coverage Approx. 1L per 1.5kg twin pack.
Curing time 3-6 hours.
Maximum operational temperature 60°C.
Pot life Up to 30 minutes.


Surfaces should be clean and free from dust, oil, grease or other contaminants. Surfaces should be sound and not friable. Any exposed steel reinforcement should be cleaned to bright metal. Some surface dampness can be tolerated, but surfaces should not be wet.


Wearing the gloves provided in the pack and using the spatulas provided, take equal sized portions of the resin (off white), and curing agent (black), and mix them together thoroughly on a suitable mixing board until they are a uniform grey colour. The ideal mixing ratio is 1:1 by weight or volume – you should try to estimate equal quantities accurately, but there is no need to weigh or measure them. Do not mix at one time more than can be applied in 15-20 minutes.


Using the plastic scraper provided, press the mixed components into the repair and smooth off the surface. Any spillages should be scraped away or wiped off with a dry cloth, and can be cleaned with white spirit. The finished repair may be filled, sawn or drilled – take care not to inhale the dust from these operations. Finished, hardened repairs may be over painted after 1-2 hours.

Case studies

£44.00 (Ex VAT)

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