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Q & A: water beading up

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Most recent answer: 05/16/2013
Q:
Hi, I really hope you can help! we have an issue with water ponding on steps due to the surface tension between the stone on the steps and the water. The stone has been sealed using a penetrative sealer. The water (despite there being fall on the steps) is sitting on the top (appox 3mm).Is there a type of coating or treatment that would serve to break the surface tension? I understand detergent can break surface tension, but i would like to treat the surface so it doesn't re-occur. Thankyou. Philippa
- Philippa
Perth Western Australia
A:
Your picture of what's happening make a lot of sense. You're looking for a more hydrophilic coating, at least for some stripes to help the water roll down off the steps. Probably some sort of silicon-based coat will work. I think you can get anti-fog treatments for windshields, so you might try some of them. However, they're likely to wear off and need to be reapplied occasionally. There may be all sorts of more sturdy hydrophilic coatings that will also stick well to your sealant, but I'm not sure which will work best. Perhaps people at a paint store would know. Anyway, you might try little strips running down the steps, so that you get the best of both worlds: the water-repelling tendency of your sealant and some water-friendly paths to help the drainage.

Mke W.

(published on 05/16/2013)

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