If you live in an older home and you find that the ceiling height in your basement is too low, you could lower the floor in one of two ways. One method is called the curb system where you don't actually underpin the foundation walls but you add a concrete curb at the base of the foundation walls after you have excavated the depth that your require. Excavation is usually in 4 ft sections. Concrete curbs are usually done if you are not planning to lower your basement by more that 30 cm or 12 inches. The reason for this is that for every 7 inches you go down you will have to project out 10 inches from the foundation wall. Example, if you go down 14 inches you will have a curb projection of 20 inches into your basement. The only way you could achieve a ratio of 1:1, that is 7 inches down and 7 inches out, would be to hire a Geological Engineer to determine if your soil would be solid enough to withstand the weight of the house. You would then submit their report to the city when you apply for a building permit.
We at Finished Basements offer Home Renovation, Kitchen Renovation, Bathroom Renovation, Basement Construction, Renovation, and Finishing services to clients across Toronto, North York, Markham, Vaughan, Milton, Oakville, Brampton, Mississauga, and Burlington, Ontario.