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Water proofing conrete in DRC


Same mission wants to know how to make concrete waterproof. We used to use Skialite poder for the skimming inside water tanks in Rwanda - info on this says it can be used for concrete as well.

What was your experience or do we have any members in Lubumbashi? That is where he is based. Sikalite may not be available there.

I suspect he would be better off walking into a friendly construction company's site office and asking there.....

Kind regards,


3 Answers

Harriette Purchas

Any more details? At the end of the day no point to improve the "waterproofness" of the concrete if you have issues with porosity, construction joints and so on ... concrete by its nature is permeable but you can very much improve that in the mix and placement and in the joints without special products.
Cheap and easy is waterbars on the joints, an improved density mix and when all else fail a flintcote (or similar treatment, even bitumen outside face) in multiple and minimum 3 thick layers brushed at 90 degrees on each consecutive coat.

If you can give more details of the issue (waterproofing, impermeability, etc) and the materials (ie a dirty sand or gravel will add to problems) there are likely simple and low cost local solutions - its not a new problem. Simple question is it a water tank or a septic tank as the solutions are different.....

Best .. Chris


He wants to make a water tank. So what he really needs is how to make waterproof cement render in the context of Lubumbashi. I have suggested using Sikalite powder - that's what we used in Rwanda. I certainly would not encourage him to use epoxy coatings.. Kind regards, Steve

Harriette Purchas gravatar imageHarriette Purchas ( 2014-01-27 11:17:32 )

If this is for ferro cement applications the usual techniques (as per handbook) work very well.. Alan


Steve, You’ve got EiE I guess. Also have a look at they have a good selection of water tank docd