A common problem in Mississaua Oakville and Toronto is that the foundation is too low and the bricks are deteriorating, starting too low. How can this problem be solved, and is it worth putting in concrete bricks instead of regular bricks, or can they be reinforced later? What you are referring to is a classic construction mistake in older houses (often found in buildings from the 1960s-1980s, including “cube” type houses), where the plinth area was poorly designed. Ceramic bricks, especially lower-grade ones, simply crumble (spall) when exposed to moisture from the ground and freezing cycles. Here's how to approach this problem:
Is it worth replacing the bricks with concrete ones?
Yes, but with some reservations. Concrete bricks (or concrete/foundation blocks) are much more resistant to moisture and compression than traditional red bricks. If you need to replace damaged sections of the wall at ground level: Concrete blocks are the best choice. They have low water absorption and high strength. Clinker brick: It is very durable and frost-resistant, but much more expensive. It is often used as a protective layer. Concreting (rebuilding): Instead of inserting individual bricks, it is often better to cut out sections of the wall (step method) and pour reinforced concrete into the space, creating a so-called “raised foundation.”
Repair methods (step by step)
If the foundation is too low, you have two main courses of action: A. Raising the plinth (replacing the lower layers) This is the most invasive but most effective method: Section by section chiseling: Damaged bricks are removed in short sections (e.g., 1 meter) so as not to weaken the structure of the house. Inserting horizontal insulation: At this stage, new heat-weldable roofing felt or thick foundation foil is laid. Rebuilding: Concrete blocks are inserted in place of the old bricks or filled with concrete. B. “Bathtub” insulation and lowering the ground If you do not want to replace the bricks, you can try to isolate them from the source of the problem: Lowering the ground level: If possible, remove the soil around the house to expose the foundation. Perimeter drainage: Drain rainwater away from the walls to keep the ground around the bricks dry. Waterproof screen: Install vertical insulation made of roofing felt/bituminous compounds up to a level of 30-50 cm above the ground.
What about “reinforcement” (shotcrete/thickening)?
You mentioned “reinforcement” (probably meaning strengthening/thickening). You can make a so-called reinforced concrete jacket: You dig up the foundation. Drill holes in the existing foundation and insert reinforcing bars (anchors). Add reinforcement and formwork for a new “wall” 10-15 cm thick, which overlaps the deteriorating bricks. Pour concrete. This creates a new, tight, and strong barrier that takes over the load and protects the old brick. Summary and recommendation Replacing deteriorating brick with concrete or concrete blocks is a very good idea. Brick in the ground is always a ticking time bomb. Important note: The order in which you do this work is crucial. Never dig up the entire house at once and do not knock down too long sections of walls, as the house may settle or crack. Work in sections of approx. 1-1.5 meters. Are you planning to do this work yourself, or do you want to prepare guidelines for a construction crew?
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