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mainegrammy

Fieldstone foundation--how to plug big gaps?

mainegrammy
10 years ago

Our home was built c. 1800. It has a dirt floor cellar & rough fieldstone foundation, mostly huge stones, very stable.

When we bought the place 40+ years ago, the gaps between stones had long-ago been chinked with bricks and rocks (4" to 12" across). Some flat, some roundish, etc., held in by mortar, old and new.

Most have gradually fallen out. For years I plugged the gaps with wads of newspaper and fistfuls of fiberglass insulation jammed in as hard as I could with screwdrivers.
Too busy with other projects to do more. Small animals burrowed through, so I packed in more fiberglass. But we could still see daylight through the cellar wall here and there...

I've now pulled out most loose rocks (etc) and gone over the walls with whisk brooms & shop vac, getting out much loose grit/dirt/fiberglass. I'd like to stick rocks and broken bricks back into those holes and secure them--but HOW?

Upper holes show daylight (not shown in photo--that area was replaced with cement when cellar door was moved in 1970s). Several below-ground holes go all the way back to the underside of flowerbeds, where rodents tunnel open "chimneys" for air to escape (largest spaces not shown in photo). Not worried about water leaks. Just want cellar to be more rodent-proof and waste less warm air in winter.

Considering shoving pebbles/small rocks into deepest holes & cementing in place; after cement dries, shoving in larger rocks & more cement, & pushing cement into the narrower places. Apparently need an old-fashioned cement intended to gradually rot away. Alternative: cram in fresh fiberglass insulation.

Has anybody done repairs of this sort, who can advise me?

Comments (11)

  • worthy
    10 years ago

    Unfortunately, shoving in rocks, bricks, Portland cement-based mortar, newspaper and fibreglass into the gaps doesn't qualify as "fixing" a rubble stone wall.

    See link.

    Here is a link that might be useful: Repairing rubblestone foundations

  • mainegrammy
    Original Author
    10 years ago

    Thanks for the page of links! Now I know what to Google. I'd been unfamiliar with the term "rubblestone." I'll check out those links.

    There's no sign of the foundation changing in the past 40 years--no changes in the way doors close or other differences in the 1st and 2nd floors with its post-and-beam construction.

    It's reasonably water-tight (some water has always leaked in at the base of one corner; it follows a trench to a sandy spot where it sinks away).

    I'm not so much trying to "fix" our cellar's foundation walls as to plug up air leaks and make it a bit more challenging for rodents to get in. Basically we hope to patch it up more or less the way the previous generations did.

    We just heard from the guys who haul in our firewood each fall--suddenly our cellar work has to be done within the next 5 days due to their schedule. Looks like we'll be stuffing fiberglass into the cracks again.

    I did note in some article links (just started reading them) that there's a danger in repairing only from the inside--I can see there's more to this than I'd imagined. Sadly, we can't afford a major (or minor) engineering project. The house needs to stay intact about 15-20 years (our maximum expected lifespan), which I think it will do.

    Thanks again!

  • worthy
    10 years ago

    The mice will be grateful for the fiberglass and newspaper you're providing them with to build their nests. Instead, try hardware cloth at the openings.

    house needs to stay intact about 15-20 years (our maximum expected lifespan)

    Friends have been buying, and rebuying, their "last" car for the last ten years. I'm staying away from green bananas!

  • mainegrammy
    Original Author
    10 years ago

    Thank you for the hardware cloth suggestion. It could make a useful rodent barrier if installed in large sheets from the top of the foundation into the dirt floor, allowing for some individual rocks that stick out 6" here and there.

    I can't see any way I could use it to patch hundreds of individual holes 1/2 to 6 inches across, though, as needed to keep out drafts.

    Yes, it's true about the fiberglass making nice rodent homes. That has been found in the past. We've decided to invest in a third cat. :)

    Well, fresh fiberglass has been shoved into place, largely with the business end of a screwdriver. This year's effort was reduced to this one possibility, as today we were informed that the 7 cords of firewood will be hauled from our yard and piled up along the cellar walls tomorrow!

    Yesterday we happened to take a tour of homes in nearby Wayne, Maine, and saw some gorgeous stone work at one. Talked to the owner, who told me his son is a stone mason... We'll be checking into his services for next year, just in case he can come up with a repair estimate that's affordable.

  • edlincoln
    10 years ago

    I don't know the "right" way to fix this, but I've been researching into lots of "redneck repairs" for cracks lately.

    Forget about newspaper. It can get moldy, bad idea. Start put by sticking wire mesh in the big gaps as a rodent barrier. Spray "Great Stuff" Insulation in. I love Great Stuff...rodents can chew through it, but if they bite into wire while trying it wil hopefully discourage them. Then cover over with (wet) mortar or DAP Latex cement basement gap filler. I used a tube but they do have a big tub you mix yourself. You can get these sorts of products at Home Depot...ask the nice folks there for advice.
    You should also go outside and plug these gaps from outside wherever practical. In theory you should dig to expose the foundation and plug leaks from outside, but I'm not sure if that is safe with your type of foundation.

    There is also an injectable epoxy for basement cracks, but I think that is more for poured stone foundations.

    This post was edited by edlincoln on Thu, Sep 19, 13 at 11:53

  • AAA333
    10 years ago

    You said : Considering shoving pebbles/small rocks into deepest holes & cementing in place; after cement dries, shoving in larger rocks & more cement, & pushing cement into the narrower places. You Can do it your self. Get just "add water" masonry mix, a cement / concrete fortifier or Acryl 60 to add to the water when mixing. ( It helps cement to adhere to no porous material like stone) and some masonry tools. Tuck pointing tools , 1/2" - 3/8" tuck point tool , and a trowel. You can mix in a plastic bucket or on a piece of plywood at least 2' x 2'. Wear gloves when applying cement ( it is very alkaline) apply 1/2" or so of cement then a rock then cement then another rock for bigger holes. Apply more when the cement hardens a little.- Like a car body filler-. ( All at once it will fall out ). When cement is flush with the rocks let the cement set a little ( not wet it will smear )and brush it out. A soft brush, Paint brush, etc... It is easy to do, If I can do it you can do it. Unless your physically unable to do it.

  • AAA333
    10 years ago

    Where do you live ? Me - buffalo

  • mainegrammy
    Original Author
    10 years ago

    Many thanks to those who keep replying! FYI, we're in Maine. We just got an estimate from a mason whose work we've seen elsewhere. He visited the day before 3 sides of the cellar were filled floor-to-beams with this winter's firewood, so no chance to do the project this year. We're planning to hire him next spring, assuming we can still afford the project.

    He said it'll be OK just to do the inner walls, since there's only one small area of water ingress (at the very base of one corner; not much comes in anymore, since we re-graded the way the dirt slopes around the house) and there's been no movement of the foundation since we bought the place in 1972. Thank goodness, no need to dig out around the foundation on the exterior!

    If it turns out we can no longer afford the project come spring, we'll give it a try ourselves--probably hiring a young helper for the heavy lifting-- using some of the excellent suggestions that have been offered on this forum.

    Gratefully,

    MaineGrammy

  • Kathrynne Willhoite
    2 years ago

    Hi there :) I realize this thread is several years old, but we are also in Maine and ate dealing with a similar situation in our basement built in 1900. I wondered if you might be willing to gove the name of the company you worked with as were looking for recommendations for this kind of work. Greatly appreciated!

  • mainegrammy
    Original Author
    2 years ago

    It was Forgotten Stoneworks, in Manchester. Bad news though--I just went to their website to double check, and in 2019 they were having a Going Out of Business sale (getting rid of all kinds of rocks and hardscapes). Such a shame. They did a superb job.