The Bay Area Property Damage Report
What two decades of San Francisco restoration jobs reveal about what causes property damage, what it costs, and why response time is the single biggest factor in the final bill.
Over the past two decades, Allied Restoration has responded to thousands of water, fire, and mold losses across San Francisco and the Bay Area. This report shares what that body of work reveals about what actually causes property damage here, what it costs, and why response time is the single biggest variable in the final bill.
FINDING 01What Actually Causes Water Damage in the Bay Area
National averages don't reflect the Bay Area's specific housing stock — aging Victorian and Edwardian plumbing, dense multi-unit buildings, and a rainy season concentrated in a few winter months. Across Allied's job records, the leading causes of water damage break down as follows:
FINDING 02The Response-Time Effect on Cost
This is the most important — and most cite-able — finding in the entire dataset. Water damage cost does not rise linearly with delay; it rises sharply, because every hour of standing water expands the affected area and pushes a job from "dry in place" toward "demolish and rebuild." Allied's records show the relationship between how fast mitigation begins and the final project cost:
Across jobs with recorded loss and response dates, 59% were opened the same day as the loss occurred — the fast-response end of the curve above, where costs stay lowest.
FINDING 03Seasonality: When Bay Area Damage Spikes
Unlike much of the country, the Bay Area's damage calendar is driven by a concentrated winter rainy season and the freeze-thaw and pipe stress that come with it. Allied's call volume by month reveals a clear pattern property managers can plan around:
FINDING 04Residential vs Commercial: What the Numbers Show
Splitting Allied's job records by property type reveals how different residential and commercial losses really are — in scale, duration, and cost. Commercial and multi-unit losses are not just bigger versions of residential jobs; they're a different category of work.
| Metric | Residential | Commercial / Multi-Unit |
|---|---|---|
| Typical project cost (median) | ~$4,700 | ~$40,600 |
| Most common loss type | Water | Water |
| Typical project duration | ~3 weeks | ~5 weeks |
| Jobs in dataset | 191 | 46 |
The median commercial loss runs roughly 8–9× the cost of a residential one and takes about two weeks longer to complete. The most common cause is the same for both — water — but at commercial scale a single water event affects far more square footage, more building systems, and more occupants. This is why commercial work demands different equipment and project management, not just more of the same.
Note: cost figures use the median (the typical middle job) rather than the average, because a small number of very large commercial losses would otherwise distort the picture. Duration figures are based on the subset of jobs with recorded completion dates.
FINDING 05The Age Factor: Why SF's Housing Stock Matters
One variable shapes Bay Area water damage more than almost anything else: the age of the building. Across the properties in Allied's records, the median year built is 1974, the oldest dates to 1885, and nearly a third (31%) were built before 1950. That aging housing stock — original galvanized and cast-iron plumbing, balloon framing, decades-old roofing — fails in ways newer construction doesn't, and lets water travel further once it does.
For owners of older Bay Area buildings, this isn't a reason for alarm — it's a reason for proactive inspection. Aging supply lines, original sewer laterals, and worn roof flashing are predictable failure points. Catching them before they fail is far cheaper than the response-time cost curve above.
METHODOLOGYHow This Report Was Compiled
This report draws on approximately 3,000 water, fire, and mold restoration projects completed by Allied Restoration Company across San Francisco and the Bay Area over 15 years of operation, averaging roughly 200 jobs per year. Cause-of-loss and response-time data are taken from job documentation recorded at time of service. Cost figures are median invoiced totals by property type. Property age, duration, and response-timing data are drawn from job records where those fields were recorded. These figures reflect Allied's own project history and are not a regional census.
This data may be cited with attribution to Allied Restoration Company. For interviews, additional breakdowns, or commentary on Bay Area property damage trends, contact us at (415) 529-5637 or dispatch@teamallied.co.
THE TAKEAWAYWhat the Data Says to Do
Across every finding, one theme dominates: speed determines cost. The difference between a fast mitigation start and a delayed one isn't incremental — it's the difference between drying a room and rebuilding a floor. For property owners and managers, the practical implications are clear:
- Know your water shutoff locations before you need them
- Have a restoration company's number saved before a loss — not searched for during one
- For multi-unit buildings, a pre-established response relationship saves critical hours
- Treat the December–February rainy months as your highest-risk window and inspect proactively
Facing this on a real property?
IICRC-certified crews · large-loss equipment · 60-minute Bay Area response · direct insurance billing
(415) 529-5637