Garage heaving and back 3 foot wall pushing in
Hope for help. Originally had a 36×24 garage Asked builder to put an additional 12 feet on back. Garage has never been heated. First year the (addition was installed) back wall pushed in 4 inches and cracked all the parging. Builder replaced all the blocks and reparged. Second year not so bad but blocked pushed in 1.5″and cracked the parging and now the floor heaved and cracked in many places. Called builder and he just said sorry and told me he did his dudilige. Now I’m stuck with heaving floor and cracked block work. I took all the plywood off walls and insulated with rock wool r22. Also put r22 in attic plus r10 armour shield Styrofoam. I am going to heat with 7500 watt electric heater as no one goes in or out in the winter. With all the knowledge out there do you think this will be enough or I was also thinking of digging around the building on 3 sides and insulate the blocks with styrafoam as well. If any one feels this is necessary please let me know how to do properly. When garage was 36×24 I never had a problem.
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I would hold off on putting any money into the garage until you determined why rear block wall is failing. Are you located in an area with expansive soils? Is the slope the garage is built into moving?
When builder replaced the blocks he excavated 4 feet back and put new fill in plus some 4 inch O pipe. Not sure what type of fill went back in. Garage is built on pretty level ground but at the back and side walls is been tapered up to match road way behind garage
When does the movement occur? Winter (from freezing) or when wet?
Snow bird so I leave in November and come back in first week of April. On the new back section does this occure. Roughly in middle of the 12 foot section. Have seen it heave up to 3 inches. Crack has gone across the whole 36 foot. This year wasn't to bad on back wall but it was a mild year.
4' wide, 2" thick foam placed horizontally just below the soil surface will keep the soil below from freezing/heaving.
Frost heave happens in the direction of heat flow. In this case, the low-mass garage cools down faster than the soil under and around it. As the soil finally freezes, it heaves towards the cold garage. The same thing happens in basements in vacant houses. Might have been fine for years, but one season of unheated house, and suddenly failed walls and/or heaving floor. Insulating and air sealing the garage, and heating it just above freezing should stop this.
That also sounds like a long unsupported wall with a fair amount of fill against it. This could also just be structural failure because the wall isn't reinforced enough. Or both.