Ottawa just made weather history — and not the fun kind. July 2026 is now the wettest month the city has ever recorded, according to Environment Canada data going back to 1873. About 270 mm of rain fell at the Ottawa Airport over the month, smashing the previous record and leaving basements, backyards, and rooftops across the region soaked for weeks on end.
A record nobody wanted
Environment Canada has been logging precipitation in Ottawa for more than 150 years, so breaking the all-time monthly rainfall record is no small feat. Meteorologists point to a stalled weather pattern that kept pulling moisture-heavy systems over the Ottawa Valley through most of July, turning what's normally a mix of sun and summer storms into a near-constant soak.
For residents, the record wasn't just a stat — it showed up as flooded window wells, soggy lawns that wouldn't dry out, and, for plenty of homeowners, water finding its way in through the roof.
What it means for Ottawa roofs
Roofing contractors around the city say sustained heavy rain is one of the toughest tests a roof can face, especially older ones common in neighbourhoods like the Glebe, Old Ottawa South, and Alta Vista. Shingles that were already worn can start to let water seep through after weeks of nonstop exposure, and clogged eavestroughs — a common issue given how many mature trees line Ottawa streets — can send water backing up under roof edges instead of away from the house.
The extended wet stretch also puts pressure on flat and low-slope roofs, which are common on newer condo buildings and additions across the city. Standing water that doesn't drain fast enough can add real weight and, over time, wear down roofing membranes faster than they're rated for.
Signs Ottawa homeowners should watch for
After a month like this, it's worth doing a quick check of your own roof and attic. Watch for water stains spreading across ceilings, a musty smell in upper floors, or granules from asphalt shingles collecting in your gutters — a sign the roofing material is breaking down faster than expected. Outside, look for sagging sections, visible moss or algae buildup, and gutters that are overflowing rather than draining cleanly during a downpour.
Catching these issues early matters in a city like Ottawa, where the freeze-thaw cycle that follows a wet summer can turn a small leak into a much bigger, more expensive repair once winter sets in.
Why this matters beyond one rainy month
Ottawa's record-breaking July is also a reminder that the city's infrastructure — both public stormwater systems and the roofs over our heads — is being tested by weather patterns that look less like the historical norm every year. Whether or not this becomes a trend, it's a good nudge for homeowners across the capital to get ahead of maintenance rather than wait for the next big storm to find the weak spot for them.
Source: Ottawa Business Journal
