This subject came up over the phone. I’m in Colorado and know-it-all brother is in Northern Minnesota. He bought a former 1 room school house with a basement and crapper outside. Most of the time the school house is not occupied and even if it was I would term it “occasional”. If occupied during the winter (which seems to start in July there) the place sees a little heat(localized wood burning stove in basement)–so it burns only a few hours a day).
The basement walls are buckling and the basement floor has heaved and cracked (over and over) with all kinds of other problems. I haven’t seen it in person. So I searched through my piles of mags and find plenty of foundation repair solutions. Of course, he wants something free–must be smoking something funny which might explain MN voting.
I pose the theory that the school’s spread footer foundation (frost free depth must be around 6′ there–just guessing) is defeated by the fact that the basement is sort of garden window construction. When not heated the subzero cold easily turns the basement (and the foundation/footer/slab and soil subzero. Benefit of a foundation/footer system below the frost/freeze line compromised.
Brother claims the “thermal mass” of the school atop the foundation protects the foundation walls/footer from freezing. A thermometer in the basement indicates that the basement area freezes–easily–so I don’t buy the “thermal mass”. Just “mass”.
Does anyone have any experience with this stuff? Maybe even know where I can find an article or online resource? (He is shivering in the basement but has a computer online)!
Do those turkeys look more nervous than usual? T-Day is coming. Thor
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I assume the bottom of the basement wall, just below slab line, contains the footing. The thermo mass theory is definitely the result of smoking something.
If the building is not heated the frost can certainly go below the the footing and heave the basement floor. Here in IL for walkout basement openings we step down the footing 42", our frostline, under the opening and extend the step down at least 42" into the soil or past the retaining wall on either side. During winter season we protect the footings and basement slab on new construction until the building is heated.
If he wants to save the building, he may want to fill the basement to frost protection level and declare it a crawl space. Also an inside sump system could be installed then too. Fixing the walls and floor is going to be expensive.
You are right, your brother is wrong.
Thanky, thanky. My degree had nothing to do with construction but he graduated as a mechanical engineer. Would think he might have been exposed to something. Might of been the sun instead of books. Tyr
Edited 11/6/2004 3:31 pm ET by Tyr
Maybe he paid somebody to take his thermodynamics final for him.
Houses that are closed and unheated in the winter season, in deep cold climates, are subject to frost in the soils adjacent their deep foundation walls and under their footings and basement slabs.
In building houses for this type of seasonal occupancy, extra care should be taken in site selection, design, drainage structure construction, finish grading, and selection of materials for sub-slab areas and backfill.
My experience with this kind of foundation destruction happened during the construction a new senior citizens apartment building. The architects deceided to keep an existing single family dwelling on the property and attach it to the new construction later turning it into a "social building" for the seniors.
The house was to be completed after the new construction. The house did not have its own heat, electricity etc, it was kept heated by an opening cut through the foundation into the apartment. A door was eventually placed on this opening. About January and during a very prolonged (Yukon weather) cold spell of -40 c someone shut that door closing off the heat.
About two weeks later I was on site making inspections when I entered the basement of the house it looked like giant mushrooms had come through the floor. The concrete slab was broken, shattered and lifted about 12" and I won't even describe the hardwwod floors upstairs or the gyproc. It was a disaster, I called in the carpenters to secure the beams but little could be done.
Our understanding at what had happened was that as long as the heat was on it kept the ground around the perimter of the foundation and under the slab from freezing solid. When the heat went off this ground froze and expanded, the path of least resistance was the concrete versus the other frozen material.
The surprising thing about this that when the frost did go out of the ground, in the spring, the building folded back together pretty well from where it was. Lots of cracks and bumps the hardwood sat up in places, we never did find out who closed the door, it was a costly mistake.
I am wondering if this is what happened to your house?