Can stone masonry be used as a foundation?

Yes. Stone masonry has been used as a foundation for centuries, and plenty of older New England homes still sit on stone and fieldstone walls today. It works, but it does not hold water out the way a poured concrete wall does, and the mortar between the stones weakens over time. Most stone foundations need help keeping the basement dry and keeping the wall from bowing inward. We fix those problems from the inside, and we price each repair after we see it.

If you own a home in New Hampshire, Maine, or Massachusetts built before the 1950s, there is a decent chance your foundation is stone or fieldstone. The stones were stacked and packed with lime mortar. That mortar was never waterproof. Over decades it crumbles, gaps open between the stones, and water finds its way through. The wall can still carry the weight of the house just fine. The trouble is almost always water and movement, not the stone.

Here is what we see most on stone foundations. Water seeps through the joints between stones and pools on the floor. The soil right against the wall is disturbed backfill, the looser dirt that got put back when the house was built. It drains slowly and holds water. That water leans on a stone wall and pushes through every gap. Add an NH winter, and frost heave shoves the wall inward.

For the wet basement, we do not chase the leaks stone by stone. We install the Forever Dry System: a full-perimeter interior drainage channel, a sump pump, a 12-mil wall vapor barrier, and a dehumidifier. The water that gets through the stone runs down the wall, behind the barrier, into the drain, and out through the sump. You stay dry. That system is 100% guaranteed to be dry for life! Basement waterproofing runs $3,000 to $30,000, and we give you the figure after a free inspection.

For a wall that is leaning or bowing, we stabilize it from the inside. Carbon-fiber straps hold a wall that has started to move, and they run $850 each. A power brace handles a wall under heavier load at $1,300 per brace. If the footing under a stone wall has settled, helical or push piers can bring it back, and helical piers run $2,700 per pier for the first three, then $2,200 per pier after that. You do not need all of this. A wall that is dry and dead straight needs nothing but a yearly look. We will tell you when that is the case.

You do not need exterior excavation. Some companies want to dig out around the whole foundation and seal the outside. In our field experience that fix fails in about two to three years, and it costs a lot more to do. The durable fix on a stone wall is interior drainage. That is why we do not do exterior waterproofing.

A stone or fieldstone foundation often comes with a dirt-floor crawl space or basement. Those breathe radon up out of the soil. The EPA action level for radon is 4.0 pCi/L, and the EPA suggests you consider fixing between 2 and 4. For a dirt or fieldstone crawl we install sub-membrane depressurization, which pulls the radon out from under a sealed membrane before it reaches your living space. Radon mitigation runs $900 to $6,000, and most homes land around $1,950 to $2,250.

What about a brand-new stone foundation? We do not build new foundations. We repair the one you have. If you are pricing a full foundation-wall rebuild or replacement, we price that after we see it, because no two stone walls fail the same way.

A quick word on cost drivers, so the numbers make sense. Wall length sets the drainage price. The amount of movement sets whether you need straps, a brace, or piers. A dirt floor sets the radon and the vapor-barrier work. We do not guess at any of this over the phone. We come out, we look, we measure, and you get a quote within 24 hours.

We have done this on a lot of old New England houses. We are a small crew out of East Kingston, NH, trusted by 5,000+ homeowners across New England, with a 4.9 Google rating across 250 reviews and a BBB A+ rating. We are licensed and insured. We self-perform the structural lifting and the helical installs ourselves, so the people who quote your stone foundation are the people who fix it.

Your stone foundation can keep doing its job for a long time. It mostly needs to stay dry and stay put.

Learn more on our basement waterproofing, structural and foundation repair, helical piers, and radon mitigation pages, and read the 603 guarantee.

For radon facts, see the EPA radon program and NH DHHS radon [verify]. For how foundation soil and water behave, see the DOE Building America program.

Got a stone foundation you are worried about? Call us at 603-610-1770 or book your free inspection. We will come look, tell you what it actually needs, and quote it within 24 hours.

Related questions

Is a stone foundation safe? Usually yes. The stone itself carries the house. The risk is a bowing wall or a wet floor, and both can be fixed from the inside with carbon-fiber straps (850each)ortheForeverDrySystem(3,000 to $30,000). We will tell you which, if any, you need.

Can you waterproof a stone foundation? Yes. We use interior drainage, a sump pump, a 12-mil wall vapor barrier, and a dehumidifier, not exterior digging. Basement waterproofing runs $3,000 to $30,000 and carries our lifetime dry guarantee.

Why does my stone foundation leak? The lime mortar between the stones breaks down over time, and the disturbed backfill soil against the wall holds water that pushes through the gaps. We route that water into a perimeter drain instead of fighting each leak.

Do you replace a whole stone foundation wall? We focus on repair and stabilization, not new builds. If a wall needs a full rebuild, we price that after we see it, since every stone wall fails differently.