Originally, in the Toronto area, many of the older homes that have basements were designed to accommodate a boiler, furnace or laundry area. They weren’t planned to be living spaces, but with today’s advancement in technology, what was once a dark and dingy small space could become a beautiful showpiece and part of the total square foot of living for the family.
Toronto basements that have low overheads in the basements, under pinning or basement lowering are about the only way to add additional space to an existing home. A structural engineer is the best person for this type of job and they would work closely with a licensed, qualified and experienced contractor.
Extending the height of the basement through downward extension of the walls, extra space is made that could be used for a family room, home theatre area, home office or an extra bedroom.
Underpinning is drilling holes under the concrete of the house, usually about four feet wide and separated by about eight feet of undisturbed soil. These holes are packed with concrete except for the last two inches which are filled with non-sink type grout to help elevate any possible air pockets or bubbles. Crossing from one set of four feet holes to the adjacent holes, then when these two are dried, the dirt between them is taken away and then the process continues around the basement, making the basement deeper by whatever depth the underpins are. This process allows a contractor to dig out the basement through the inside without disturbing the plant life outside.
Lowering of the basement also involves redoing of drainage pipes (replacing old often clay pipes with PVC, plus it gives an opportunity to rough in for new bathroom), installing weeping tiles, inside waterproofing, installing sump pump and pouring a new slab.
If a separate entrance to the basement is wanted, then the structural engineer could place this into the plans where it would best fit structurally. A foundation contractor would then cut into the concrete wall with a backhoe, after the surrounding wall has been secured. The doorway is framed with supports and braces for the door of your choice. If the new entrance to the basement is in the back of the house, there is no need to match the front door; however, if the new entrance is in the front of the house, then matching the front door would be a major concern. When a door has been chosen, it is lowered into place and then caulked all around to prevent water and moisture from seeping into the basement, one of the risks that can be avoided with the caulking.