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Stone foundation sealing


I just bought a home that was built in 1889. The basement is currently finished but has a lot of water damage. The drywall and panelling are warped and there is some mold present. However, the basement does not smell damp and I have not seen any water. We want to rip out all the finishing in the basement, seal the stone (limestone or sandstone I think), and refinish it. We also plan on re-landscaping to slope away from the house. The floor has drains but there is no sump pump (which may be banned by our city).

My question is, how do we seal the basement? We would prefer to do it from the inside because digging up the exterior may cause damage to the integrity of the foundation. If we had someone seal it for us, how much can we expect to pay?

Thank you!

Re: Stone foundation sealing

Before you seal or parge the stone do some research.
Check Historic Scotland publications.
Also check US Heritage Group this is the USA sister company.
On the East Coast check Cathedral Stone.
Using the wrong repairs on Brown Stone Or Lime Stone can cause more damage than good.

Re: Stone foundation sealing

Stone is tricky, and for a few reasons. First, between the stone is usually grout or some type of concrete. Unless a bonding a gent was used, there could be hairline gaps between the grout and the stone. Further, if the grout/concrete is over 100 years old, it will have weakened over the years, especially with constant exposure to water.

First step should be to repair and seal the grout/concrete. If there are any gaps, hairline cracks, or voids, repair them. Next, apply a sealer, like the Armor S2000 concrete sealer, to the grout. If the stone is not painted or sealed already, and if it contains lime and calcium, that same sealer can be used to seal the stone. If the stone does not contain lime or calcium you may have to consider a waterproofing paint or coating which will change the look of the stone walls.

If you don't know what kind of stone you have, start with applying the Armor S2000 Concrete Sealer in a test area to see if it was able to absorb and react. If it absorbs and reacts, it works as a great waterproofing sealer. If the stone won't absorb and react with the sealer, a coating is the only other option.

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