Seattle Crawl Space Data

How to read a figure from this section

Everything published here carries one of four classifications. They are not interchangeable, and the gap between the first and the third is the gap between a measurement and a judgement. Whichever number you take from this site, take its label with it.

MEASURED Measured

A value reported directly by the authority that holds it, or read out of a legitimate published dataset without alteration. A code requirement quoted from the adopted code, a sales tax rate read off the state’s rate table, a rainfall total from the National Weather Service.

DERIVED Derived

A value calculated from measured inputs by a stated formula, where both the inputs and the formula are published so the result can be recomputed independently.

MODELED Modeled

An editorial estimate: a considered judgement about what a defined scope of work costs in a market, published with its assumptions and its derivation. It is not a measurement of that market, and adjusting it by a published index does not make it one.

OBSERVED_QUOTE_DATA Observed quote data

A range computed from a sample of real quotes issued to real homeowners, published with its sample size, its median, and the dates the quotes were issued. Reserved for future use under a stated threshold of 30 quoted projects per service.

Where this site currently stands. Every published price is modeled. Nothing on this site is observed quote data — no database of Seattle-area contractor quotes exists here, and the classification is defined in advance so that the day one does, it lands in a slot whose meaning was fixed before anyone had an interest in stretching it. The cost methodology sets out how a modeled range is built.

What is not here, and why

A data section is only as good as its honesty about what it does not have. These were considered for publication and are not published. In every case the blocker is that the data does not exist or cannot be confirmed — not that the page has not been written yet.

Seattle-Area Contractor Quote Data Would be observed quote data

Zero observations exist. This site takes inspection requests, so anonymised quote data is a plausible thing to eventually hold, but it holds none today and publishes no quote statistic of any kind. What DOES exist is the full architecture, written while the dataset was still empty, because the temptation to call a thin sample a market arrives with the data, and the honest moment to set the threshold is before anyone has a stake in the answer. A service needs 30 verified quoted projects from at least 8 distinct contractors, with no single contractor supplying more than 35% of them, spanning at least six months and none older than two years. Sample size, median, contractor count and the issue-date range publish together or not at all. The schema holds no homeowner name, phone, email or address and has no key back to the table of inspection requests, so an observation cannot be re-identified from it. No contractor-level statistic will be published at any sample size.

Seattle Crawl Space Moisture and Humidity Readings Would be measured

Not publishable without instrumentation. This would be genuinely valuable, and it is exactly the sort of thing that must be measured rather than modeled. Publishing modeled humidity figures under a measured-sounding heading would defeat the purpose of this section.

Crawl Space Permit Thresholds by Jurisdiction Would be measured

Not researched to the standard this needs. There is no single authority: permits are handled jurisdiction by jurisdiction, the answer varies by scope within each, and this site has not yet confirmed any of them directly with the building department concerned. Nothing is published until each one has been, because a wrong permit answer costs a homeowner real money.

Using and citing this data

• Free to reuse with attribution. Quote it, chart it, republish it. Name Seattle Crawlspace Pros, name the review date, and link to the dataset so your reader can check the basis for themselves.
• Always carry the review date. The ranges are revised. A 2026 figure republished in 2028 with no date attached becomes a claim this site did not make.
• Do not upgrade the label. A modeled estimate described downstream as “data from Seattle contractors” is a misrepresentation, and it is the specific error this site corrected on its own pages before building this section.
• A yardstick, not a verdict. These are one publisher's estimates. Written bids for a specific house are better evidence about that house, and the bid checker is there to compare them line by line.
• Not peer reviewed, not a survey, not a market study. One publisher's documented estimates for a stated reference project, and described that way here so nobody has to describe it that way for us.

Seattle Crawlspace Pros. "Seattle Crawlspace Cost Index." Updated November 2026. SeattleCrawlspacePros.com.

Corrections

If something here is wrong, that is worth knowing and worth fixing. Tell us what and where — which page, which figure, and what you are seeing instead. Corrections that change a published number are recorded in the dataset's revision log with the date they were made, so anyone who cited the old figure can see that it moved. Regulatory status is tracked separately and was last checked November 11, 2026.

Substantive factual, regulatory and sourcing errors go further than a revision log: they are recorded permanently in the public corrections ledger, with the wording as it stood, the correction, and what a reader relying on the original would have got wrong. None is recorded there yet.