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eroding bricks and stone foundaiton solutions

I just moved into a home build in the late 1800s and the stone foundation and bricks in the chimney (from the basement up to the top of the second floor) are eroding away (flakes and piles of shedded mortor/stones in the basement and mortor and sand-sized pieces of brick collected on all adjacent floors). I assume that this is due to the amount of lime in the mortor that was used in that time period breaking down.

In addition to repointing the concrete is there anything else I can brush on these surfaces (especially the bricks) to prevent this from continuing?

Re: eroding bricks and stone foundaiton solutions

Hi, I just read your post on here about the bricks in your foundation eroding and turning to dust. I too live in a home built in 1836 and in my basement, there are several walls made of brick doing the same. I have dry vac'd several wheelbarrow loads of brick! I have asked the same question , if there was some type of sealant to put on the remaining bricks, but have never gotten any reply. Have you? If so, I would be very interested to know. Thanks and good luck.:)

Re: eroding bricks and stone foundaiton solutions

The problem is moisture migration and the salts breaking down the mortar.
As for a repair you can repoint the joints.
When repointing you MUST make sure you use the correct repair mortar.
Up to 1864 in most areas mortar used was Quick Lime and sand and after 1864 in some areas it may contain portland cement.
If the incorrect mortar is used for repointing the rate of failure could and most likely will increase.
Your best repair type mortar would be an exact match to the existing.
If you can't find the match use a very week TYPE " O " mix with a PSI of 350 not to exceed say about 500 PSI.
You can find most early mortars at one of the following.

U.S. Heritage Group

A. W. Cook has a very good mixture.

Virginia Lime Works

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