Where strata leaks start
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Plumbing accounts for about two BC strata leaks in five. Most leaks begin in common property, a third reach beyond the unit where they started, and older buildings record about three times as many per door as new ones.
Water is the one thing every strata council talks about sooner or later. A leak shows up in the minutes as a line or two: a stain on a ceiling, a call to the plumber, a restoration company, sometimes an insurance claim. One line is an anecdote. Thousands of them are a map of how buildings get wet. We took 2,000+ samples drawn from our pool of BC strata reviews, pulled every water incident the council and general-meeting minutes describe, and sorted them by what failed, where it started and how far it travelled.
2 in 5 | ~88% | 1 in 3 |
|---|---|---|
BC strata leaks that start in plumbing | BC stratas with a leak in about two years of minutes | BC leaks that reach beyond one unit |
Nearly every building has some
About 88% of BC stratas record at least one water incident in their minutes, which typically cover about two years. The median building logs four incidents in that window, with the middle half between two and eight, and about one building in six logs ten or more. Per year, that is a median of about two incidents per building. Larger buildings log more in total, since they have more pipes, but fewer per door: a typical building records about 2.7 incidents per 100 units per year, with the middle half between about 1.2 and 5.2.
Pipes first, then drains and roofs
| Category | Share of incidents |
|---|---|
| Plumbing | 41% |
| Drainage | 17% |
| Roof | 13% |
| Building envelope | 8% |
| Fixture overflow | 5% |
| Sprinkler | 3.5% |
| Burst pipe | 3.3% |
| Flooding | 3% |
| Window | 2.9% |
| Other | 3.4% |
Plumbing leads at about 41% of incidents: supply lines, drain stacks, valves, fittings and the connectors under sinks and toilets. Add the burst pipes, about 3% on their own, and close to half of all leaks are the building's water system failing somewhere along its length. That is close to what insurers have reported for condo claims elsewhere in Canada, where pipe problems were behind about half of water-damage claims in a 2014 survey. [3] Drainage comes second at about 17%: blocked catch basins, area drains, sumps and stacks that back up. Roofs are about 13%, the building envelope (walls, balconies, membranes) about 8%, and windows about 3%. Fixture overflows, the tub left running or the washing machine that let go, are about 5%. Sprinklers and floods make up the rest.
Most start in common property
About 65% of incidents start in common property and about 23% start inside a unit; for the rest the minutes do not say. That split is why a leak is so often a strata matter: the pipe in the wall, the drain under the parkade and the membrane under the balcony usually belong to the strata, even when the water ends up on someone's kitchen floor.
Where the water goes is a different question. About 35% of incidents stay inside a single unit, about 30% touch only common areas, and about 31% spread further: to the unit next door or below (17%), across several floors (9%) or through the whole building (5%). Each cause has its own shape:
Fixture overflows almost always begin in a unit (about 92%) and are the most likely to travel: about 62% reach beyond it. Water from a tub runs downhill through other people's ceilings.
Roof and window leaks stay local. About 60% of roof leaks and 76% of window leaks affect one unit, usually the one under the roof or behind the glass.
Drainage is a common-area problem: about 54% touch common areas only. About 13% of all incidents are in the parkade, and nearly half of those are drainage.
Burst pipes and floods are rare but serious. About one recorded leak in eight is rated high severity overall; for burst pipes it is about 58% and for floods about 49%.
About one leak in three leaves the unit it started in. Water from a tub runs downhill through other people's ceilings.
Older buildings record more per door
| Category | p25 | Median | p75 |
|---|---|---|---|
| Before 1980 | 2 | 4.3 | 6.9 |
| 1980s | 2.4 | 4.3 | 7.7 |
| 1990s | 1.8 | 3.8 | 7 |
| 2000s | 1.2 | 2.5 | 4.2 |
| 2010 to 2015 | 0.9 | 1.9 | 3.3 |
| 2016 or later | 0.6 | 1.3 | 2.6 |
Per door, the rate falls steadily with the age of the building. Stratas built before 1990 record a median of about 4.3 incidents per 100 units per year, the 1990s about 3.8, the 2000s about 2.5, and buildings from 2016 or later about 1.3. Pipes, membranes and seals age, and the newest buildings are also still inside the home warranty period, when some repairs are handled outside the strata budget. Construction shows the same pattern from another angle: wood-frame stratas record about 3.3 incidents per 100 units a year and concrete stratas about 1.9, although a concrete tower logs more incidents in total because it has more doors.
Some leaks stay on the agenda
About 59% of incidents are mentioned at one meeting and never again. About 25% are still being discussed three months later, and about 7% a year later. The slow ones are the ones with a hidden source: about 42% of burst pipes, 32% of drainage problems and 31% of envelope leaks are still in the minutes three months on, against about 17% of fixture overflows, where the source is usually obvious and the fix is a plumber's afternoon.
What to do with this
If you are buying: search the minutes for "leak", "water", "restoration" and "drain". A few incidents in two years is ordinary; the same cause coming back, or one incident that stays on the agenda for months, is worth a question.
If you own a unit: the most common leak that starts inside a unit is an overflow or a failed connector, and it is also the kind most likely to reach your neighbours. Check what your bylaws say about who pays the deductible. [1] [2]
If you are on council: drains and parkade catch basins are a large share of what goes wrong and among the cheapest things to maintain on a schedule.
How we counted. Based on 2,000+ samples drawn from our pool of BC strata reviews. Figures come from the council and general-meeting minutes in those samples, mostly 2023 to 2026. Each water incident the minutes describe is counted once, with its cause, where it started and how far it spread as the minutes record them. Rates divide a corporation's incidents by its unit count and by the years of minutes read, for corporations with at least a year of minutes. Figures are medians and the middle half (p25 to p75) or shares of incidents, rounded. No building is identified. If you use these figures, a link back to this post is appreciated.
Further reading
Frequently asked questions
What is the most common cause of water damage in a BC strata?
Plumbing: about 41% of the water incidents recorded in BC strata minutes, or close to half with burst pipes included. Drainage is second at about 17% and roofs third at about 13%.
How many leaks does a typical BC strata have?
The median BC strata records about two water incidents a year, or about 2.7 per 100 units per year. About 88% record at least one in roughly two years of minutes.
Who pays when a leak starts in my unit?
A strata insurance deductible is a common expense, but the strata can recover it from an owner who is responsible for the loss, and depending on the bylaws that may not require negligence.1, 2 Owners can insure for that exposure on their own policy.
Do older buildings leak more?
Per door, yes. BC stratas built before 1990 record about 4.3 incidents per 100 units per year at the median, against about 1.3 for buildings from 2016 or later.
What happened in a building, and whether it is normal
StrataReports reads the full document package of one strata or condo building and reports what happened in it. It then compares the whole building with similar buildings nearby, from finances and insurance to repairs, the condition of its components and disputes, and shows what is normal and what is not. Every finding links to its source page.