Portland's certified mold inspector — Garrett Dayfield, MTSO
I’m Garrett Dayfield, owner and operator of MTSO
We are a Portland-based mold inspection and testing company serving residential and commercial clients across the Portland Metro area and Southwest Washington. A second-generation mold inspector, Garrett joined the family business in 2005 and assumed ownership in 2012 — carrying forward the standard of excellence his father established when the company was founded in 2002.
Certified by MICRO (Mold Inspection Consulting and Remediation Organization) and recognized by the City of Portland, Garrett has personally completed thousands of mold inspections, bringing the same thorough, solutions-focused approach to every property he visits.
Through MTSO, Garrett offers a comprehensive range of testing services — including mold and mycotoxin testing, indoor air quality assessments, and certified radon testing — for residential and commercial properties throughout the Portland Metro area. Every inspection is conducted personally by Garrett, ensuring consistent, expert-level service on every project.
Learn about the health benefits of a MTSO service here
Serving Portland and the surrounding area
MTSO provides mold inspection and testing services throughout the Portland Metro area, including Beaverton, Lake Oswego, Gresham, Tigard, Hillsboro, and surrounding communities. We also serve Southwest Washington, including Vancouver and the surrounding area. If you're unsure whether we cover your location, give us a call — we're happy to help.
Yes, MTSO serves Southwest Washington in addition to the greater Portland Metro area, including Vancouver, WA and surrounding communities.
We do not accept samples for analysis, as we focus on conducting on-site inspections and tests.
No, we charge for our mold testing services to ensure impartiality and objectivity in our results.
No. MTSO specializes exclusively in mold inspection and testing and does not perform remediation. This separation is intentional — it ensures our findings are always objective and free from any conflict of interest.
Yes. Garrett Dayfield holds certification from MICRO (Mold Inspection Consulting and Remediation Organization) and is recognized by the City of Portland. MTSO is also fully insured.
Yes, we offer mycotoxin analysis, conducted by RealTime Labs, a recognized leader in the field.
Every project is unique, just like the clients we serve. Interested in learning more about our services and how we can support your specific needs? Give us a call, and we’ll provide a tailored quote that fits both your project requirements and budget.
If you’d like further clarification or wish to discuss your concerns in more detail, we’re happy to schedule a video or phone consultation at your convenience.