Mold Testing in Seattle, WA

Start with the question, not the sample

A lab result is only useful if it answers something you actually need to know. Before you book anyone, write down why you want the test. Common Seattle reasons include a stale odor in a closed-up guest room every winter, a daylight basement that smells damp after weeks of rain, a home inspection that flagged staining in the crawl space, or a rental unit where the tenant and landlord disagree about what is going on.

There are no EPA or federal limits for mold or mold spores, and the Washington Department of Health points out that even a clean, dry house has some spores in it. So a test will almost never return a simple pass or fail. What it can do is compare indoor air to outdoor air, show whether a hidden area is contributing spores, or confirm that a cleaned area is free of growth.

Testing is worth it when

• You smell mold but a visual inspection with a moisture meter finds nothing obvious.
• You are buying or selling and want a written record of conditions.
• You need documentation for a landlord, a property manager or an insurance claim.
• Remediation is finished and you want clearance before walls go back up.

Testing is usually a waste when

• You can already see growth on drywall, window frames or attic sheathing.
• You are using a store-bought settle plate, which grows something in nearly every house.
• The person taking the samples is also quoting the removal and has not explained what each sample is meant to show.

Sample types and national price ranges

These are national figures. Prices around Puget Sound vary with the number of samples, home size, crawl space or attic access, and how fast you need lab results. Ask for the price per sample and the lab fee in writing.

What a good report gives you

Expect the inspector to note where each sample was taken, include an outdoor control sample for air tests, list moisture readings, and explain the results in plain language with a recommendation. A report that only lists spore counts with no moisture findings leaves you without a next step.

Picking who tests

Washington has no state mold license or certification, according to the Department of Health, so anyone can offer testing. Voluntary credentials exist, and DOH points people who need an indoor air consultant to industrial hygiene firms. Angi recommends using a different company for testing than for removal, so the person interpreting results has nothing to sell you afterward.