Experiencing water in your basement for the first time can be alarming—especially when you’re living in a 100+ year-old home near Toronto’s historic Annex neighbourhood. After four years without issue, an intense rainstorm suddenly results in 10 to 15 litres of water pooling on your engineered hardwood flooring. You clean it up quickly, but you’re left wondering: what now?
This type of unexpected flooding is a common concern for many older Toronto homes. Most homes built a century ago were never designed with modern waterproofing techniques. And over time, even the most solid foundations can develop cracks or weaknesses that allow water in during periods of heavy rainfall or high groundwater tables.
So, what should a homeowner do when this happens?
First, act fast. Soak up any visible water as soon as possible and use fans and dehumidifiers to thoroughly dry the affected area. Mold and mildew can begin growing in as little as 24 hours. In your case, water seeping between floorboards is a sign there may still be moisture trapped underneath, which could lead to long-term damage if not dealt with properly.
Next, try to identify where the water entered. Is it coming from a basement wall? A floor joint? A window well? If you’re not sure, it’s best to contact a waterproofing specialist for a proper assessment.
In Toronto, many homeowners opt for exterior waterproofing to address these issues long term. This involves digging around the foundation, applying a waterproof membrane, and installing or repairing weeping tile systems to direct water away from the structure. While this is often the most effective solution, it can also be the most expensive.
For those seeking a more cost-effective or less invasive option, interior water management systems are another solution. These typically involve installing interior drainage channels connected to a sump pump, which collects and redirects water out of the home. Though not true waterproofing, it’s a solid strategy for managing ongoing seepage and preventing future damage.
Another option is trenching around the interior perimeter of your basement slab and installing a perforated pipe system. While this doesn’t stop water from entering, it efficiently collects and redirects it, reducing the risk of accumulation.
Regardless of which solution you choose, keep in mind that older homes rarely have waterproof basement slabs. So, even if your walls are sealed, water can still enter from underneath. For ultimate protection, some homeowners opt to remove the existing slab entirely, install a full waterproof membrane underneath, and pour a new slab over top—a major renovation, but one that virtually eliminates future seepage from below.
If you’re a Toronto homeowner dealing with this for the first time, you’re not alone. Many clients I’ve worked with have faced the same challenges and felt equally unsure of what to do. The key is not to panic. Get the space dry, assess the cause, and speak with trusted professionals who understand the intricacies of older Toronto properties.
Taking action now not only protects your home’s value but also ensures peace of mind when the next storm rolls in.
Richard Wang 