waterproofing old stone foundation home.. i need some help!

Questions and answers relating to houses built in the 1800s and before.

Moderators: oldhouse, TinaB, Don M, Schag

Posts: 2
Joined: Sat Nov 22, 2014 4:17 pm

Re: waterproofing old stone foundation home.. i need some he

Post by FOHRSKI »

Unfortunately, I came upon information like on this thread too late. My question revolves more around, how worried should I be now that I've had work done on my basement foundation.

My house was build in 1865, field stone foundation, and a "Michigan basement". 25% 6'high basement, 75% crawspace. I didn't have any significant leaking in the walls, other than in one corner, when it rains extremely heavy, which could possibly be a result in my water table rising with hairline cracks on the floor in that corner.

I ended up hiring a contractor to do an exterior waterproof on my stone foundation walls. They excavated around the entire house down to the footing (which was only 6" high). They cleaned out all the dirt out of the gaps in the wall with an air compressor, and pointed the entire wall with portland cement for the most "even" up to down finish they could. They then tarred the rest, put up visquin, then a plastic dimple board, tarred & flashed the top of the dimple board. They backfilled the excavated areas with the original dirt/clay, other than about 20% 30a stone with a french drain, that leads to my sump pump in the basement.

My stone foundation wall is thick. I'd say between 1'6" - 2' wide. Reading on how portland can "destroy" lime-based mortar stone foundation walls......Should I start worrying that I caused a real near-future problem for my foundation?

Any opinions or comments would be greatly appreciated. Also.....my stone foundation stops about 1' above grade level, before the house brick starts. (House wall brick is 3 bricks deep all the way to the roof, btw). So, I was thinking of slapping on some cultured stone between grade level & where the brick starts. Is that a bad idea? Does this lime-based foundation need to breath?

Posts: 4
Joined: Sun Dec 14, 2014 7:11 pm

Re: waterproofing old stone foundation home.. i need some he

Post by philupthegastank »

Hi all,

I made the mistake of painting my field stone basement with sealant. Im young and uninformed haha. I did not seal the bottom of the wall to the basement floor though so that when it rains hard, it just forms streams that pour out at the bottom of the wall that either floor my basement or travel to the sub pump.

What can I do to correct what i did wrong?

Inspector Pete
Posts: 186
Joined: Wed Sep 13, 2006 5:07 pm
Location: Syracuse, New York

Re: waterproofing old stone foundation home.. i need some he

Post by Inspector Pete »

To quote myself from 8 years ago in this thread,
"As someone that has evaluated hundreds of stone foundations, the importance of exterior water control cannot be over emphasized. To add to the Preservationist suggestions above, which are great, I see good intended improvements go bad sometimes. Make sure the gutter downspouts extend far away from the building to guarantee water won't flow back to the house - check with a garden hose - six feet or more of extension is not uncommon. Make sure the grading pitch is at least 1" drop for every 12" from the house for the first five feet. Never, never water proof a foundation from the inside with a sealant paint. Once water enters the foundation, it is necessary to allow it out. Trapped water ruins mortar, rots cinderblock, and causes pressure that can ruin foundations. Once you've done the basic exterior water control, remember that old house foundations are not supposed to be waterproof - buy a 1980's raised ranch if want a dry basement :) ."

All you can do now is let the water proofing paint flake off with time, and it will.

Good luck.

Posts: 5
Joined: Mon Dec 29, 2014 8:08 pm

Re: waterproofing old stone foundation home.. i need some he

Post by sk3499 »

You want to be very careful about waterproofing a stone foundation wall. If hydrostatic pressure builds up on the outside it could push the wall in. Water coming thru the wall relieves the pressure as it is now.

I know cause I have a 1725 saltbox with stone foundation and I have talked with several waterproofing companies. In my particular case, the pressure can be very high, the water shoots out of my basement wall like a hose when it rains. The may have to do more with groundwater than surface water as I am in a low area. None of them recommend trying to do complete waterproofing because the pressure could push the wall in. Instead I have a french drain and sump pump inside. I also had gutters, but had to remove them, they were causing too many ice-dam problems in the winter. If you do put gutters on and you live in a cold winter climate, I suggest paying for heated gutters.

Posts: 1
Joined: Wed Dec 18, 2019 12:01 am

Re: waterproofing old stone foundation home.. i need some he

Post by alexanderrozhenko »

A foundation is a structure that creates a strong level base on which we build.
A stone foundation has several characteristics when compared to other foundation types.
1. Water penetration
2. Compressive strength
3. Durability

Foundations are an important component of the building and it should be inspected annually to determine if any repairs are needed.

For any type of assistance, get in touch with Prompt Building Inspections, they are well-known building inspections provider in Perth.

Post Reply