# Exterior Stone Foundation Parging/Sealing



## joecaption (Nov 30, 2011)

Sorry water proofing is just not going to happen with that mess.
You need a whole new foundation.
Is that sandstone?


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## TRUEPRO (Apr 10, 2012)

You need to parge a couple coats of portland on there and fill every void possible until you have a flat like surface. The go buy some "DRYLOCK" concrete waterproofer. Coat several times. This will prob be you best chance of keeping water away without having to redo the who job. GOODLUCK


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## jmack17m (Jul 17, 2012)

@JoeCaption - It is fieldstone/sandstone. I had a building inspector out to look at the foundation and he assured me that it's structurally sound. It is just uneven is all. Water doesn't really even get near the wall, so I'm just looking for a way to make it look OK and not have the parging break apart in a year.

@TRUEPRO - Thanks for the tips! I suppose I'll give that a shot and see where I stand.

I'll try and post pics if I'm successful.

Thanks for the insight guys.


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## TRUEPRO (Apr 10, 2012)

Do several thin coats. Perhaps look into a bonding agent to add to the portland mix. Dont try to go to thick because the mud will sag and leave you with ripples. Trial and error with the sand/portland mix. Should be close to 1:1:3 Portland/bucket of water/Sand


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## Vikerlund (May 22, 2019)

Hello,
I am curious on how this project turned out as I have a similar dilemma myself. Stones, (rather big) Stacked under the slab the car port is on.


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## ClarenceBauer (Mar 4, 2005)

The advice to use the Portland cement product on Old Limestone was BAD advice. You would not want any mortar stronger than the existing. If you can't get the mortar checked for it's PSI than go with a Natural Hydraulic Lime product. ( NHL ) there three types with different PSI's NHL-2 , 3 & 5 check to see which one fits your existing mortar. Than you could also use a type "O" mortar you can mix this or buy it premixed make sure you check the MAX PSI on the selected mortar.


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