Is it possible to improve a sinking garage foundation without rebuilding the entire garage? Yes, it is possible. Still, the answer is the same as it was before. Typical house garage foundations are considered small structures, so “jacking” (sand jacking, mud-jacking, slab-jacking) is the preferred method for treatment. The alternative that you were thinking of, piering, is typically only used on larger commercial buildings, schools, etc. There is also a list of things to look for that are major foundation warning signs, such as diagonal cracks.
Important! Another note on garage and basement floors. Do you want a heated garage? If so, you should design your garage floor to be an insulated concrete slab, otherwise without a thermal break separating the ground from the soil, that will just be a place to suck heat out to the frigid exterior.
20181009/DuckDuckGo improve garage foundation without rebuilding
20181009/https://www.concretenetwork.com/concrete/foundation_repair/
20181009/http://starcraftcustombuilders.com/garage.htm
This is another interesting article about someone building their own garage. Especially useful is the mention of their thermal treatment of the floor.
20181009/https://www.mrmoneymustache.com/2017/01/24/diy-studio-building/
Now for some random articles.
20181010/https://www.mrmoneymustache.com/2013/03/16/reader-case-study-this-guy-doesnt-need-my-help/
20181010/https://www.mrmoneymustache.com/2012/11/01/our-new-237-per-month-health-insurance-plan/
Very interesting! Doubling your salary doesn’t have as big of an improvement on your net worth as cutting your unnecessary spending.
20181010/https://www.mrmoneymustache.com/2012/11/14/doubling-your-salary/
20181010/https://www.mrmoneymustache.com/wp-content/uploads/2012/11/double_salary_1024.jpg
20181010/https://www.mrmoneymustache.com/2011/09/30/is-a-costco-membership-worth-the-cost/
20181010/https://www.mrmoneymustache.com/2011/05/10/ill-show-you-my-electricity-bill-if-you-show-me-yours/
20181010/https://www.mrmoneymustache.com/2011/05/06/mmm-challenge-cut-your-cash-leaking-umbilical-cord/
20181010/https://www.mrmoneymustache.com/credit-cards/
20181010/https://www.mrmoneymustache.com/2016/11/24/efficiency-is-the-highest-form-of-beauty/