Mold Inspection and Testing in Portland: Find It, Document It, Then Decide

Is there a license for mold inspectors in Oregon?

We found no Oregon mold-specific license for inspectors or assessors, and no Portland mold rule. Credentials from industry groups are voluntary. Ask the inspector about training, how many inspections they have done, what equipment they use and whether they also sell remediation, which can be a conflict of interest.

A contractor's CCB license is separate and applies to construction work, not to taking readings. If an inspector is also offering to do the repairs, check their CCB license as you would anyone's.

Ask for a sample report. A good one has photographs, readings with locations and plain recommendations.

Should the inspector and the remediator be different companies?

Often it helps. An independent inspector has no stake in how much work is recommended, so the scope is easier to trust, and the same person can check the work afterward. For a small, obvious problem it may not be worth the extra step.

When the same company diagnoses and repairs, the scope may be fine, but you have no outside check. When different companies do it, you have a reference document and a second look.

After a flood, a sewage loss or growth inside walls, the separate inspection is more often worth it.

What do mold tests actually tell you?

They tell you what was in the air or on a surface at the moment of sampling. They do not give a safe level, and results shift with weather and activity. They are most useful alongside moisture readings and a visual inspection, and least useful as a stand-alone reassurance or alarm.

The EPA's guidance says that if you can see or smell mold, you should find and fix the moisture instead of relying on sampling to decide whether to act.

Testing can still serve a purpose, such as confirming clearance after cleanup, settling a dispute or checking a space you cannot see into.

Where does mold hide in a Portland house?

In the places that stay cool, damp and unventilated: behind finished basement paneling, along crawl-space joists, in attic corners under a leaky roof, under sinks, behind bathroom walls without a working fan and at the bottom of exterior walls. It also grows on stored cardboard, which is why basement boxes are a common first sign.

A windowless bathroom with a weak fan is one of the most common spots, especially in older houses. Steam condenses on the ceiling and walls and never fully dries.

Basements deserve a thorough look in winter, when seepage is active. A musty smell that seems stronger on damp days is a clue.

• Under kitchen and bathroom sinks
• Behind paneling or furniture against exterior basement walls
• Attic roof deck near vents and valleys
• Crawl-space joists and subfloor

What should a good inspection report contain?

A good report lists each location, the readings taken, photographs, the probable moisture source and recommended steps, with any sampling results and how they were collected. It states what the inspector could not see. It should be clear enough to give to a remediator, who can price from it.

Watch for reports that offer a pass-or-fail verdict from spore counts alone. Counts vary with weather and time, and no single number marks safe from unsafe.

Ask whether the inspector will return after the work to confirm it. That is a separate visit, and it is useful.

How should you prepare for an inspection?

Note when leaks or floods happened, where smells are strongest and which rooms trigger symptoms. Clear access to basements, attics and crawl spaces, and keep pets away from work areas. Do not clean visible mold first, because the inspector wants to see it. Gather past repair records.

If you are buying a house, ask whether the seller's disclosure mentions water. Past repairs, patched ceilings and new paint on lower walls are clues worth mentioning.

Bring up any health concerns with your doctor, since an inspection will not answer them.