The Best Mold Inspectors
We graded 61 companies on seven things customers actually report: satisfaction, reliability, workmanship, value, momentum, track record and how owners handle complaints.
From 23,247 Google reviews of 61 top-rated mold inspectors nationwide. Updated October 29, 2026.
Find the right company for your job
Pick the job — we re-rank companies by how customers rated that exact job.
Best mold inspectors for environmental due diligence
Clear ✕Job match = this company’s ★ on reviews Google tagged “Environmental due diligence” (shrunk toward the category average when there are few), how many such jobs it has done, and its overall Experts Score.
What customers said about environmental due diligence
Had a fantastic experience with this company. Garret is very knowledgeable. He promptly answered all my questions and concerns. His testing and sample collection was extremely thorough and punctual. I was very impressed with the reports provided. Absolutely recommended for anyone that wants to know for sure the mold…
Great experience from very first contact to receiving the final results. Garrett was phenomenal at communication, attention to detail, and incredibly skilled in mold detection and analysis. The whole process was painless and efficient. Highly recommend!
Garrett Dayfield of Mold Testing Services of Oregon, LLC did an excellent job of assessing my house, inside and out, with ample pictures, thorough descriptions, and suggestions for addressing problems with mold and other air quality issues. Use this service earlier rather than later. Mold is dangerous!
Garrett with Mold Testing Services was very helpful, fast and efficient after we had a water leak vehind the wall that turned out to be moldy. I wiah everyone was as clear and professional as he is!
MTSO was very prompt and professional. Got us insights into our home situation quickly so we could figure out next steps. Thanks Garrett.
Garrett was extremely professional and prompt! The results came in a timely fashion. Thank you Garrett!
Overall ratings
Experts Score 0–100Experts Score (0–100)Absolute quality first: recency-weighted star average (≈54%), share of 1–2★ reviews (≈24%), customers’ price verdicts (≈14%), owner replies to critical reviews (≈7%); minus up to 10 points each for complaints flagged in Google review highlights and for a real slide in recent ratings. Hover a company’s score on its page for the full breakdown. and a letter grade per factor (A = top 20% of mold inspectors).
| # | Company | ScoreExperts Score (0–100)Absolute quality first: recency-weighted star average (≈54%), share of 1–2★ reviews (≈24%), customers’ price verdicts (≈14%), owner replies to critical reviews (≈7%); minus up to 10 points each for complaints flagged in Google review highlights and for a real slide in recent ratings. Hover a company’s score on its page for the full breakdown. | FactorsFactor grades, in orderSatisfaction (54%): Recency-weighted star average (2-year half-life), shrunk toward the category mean by review volume; the company’s own lifetime average as the prior; absolute: 4.0★ = 0, 5★ = 100.Reliability (24%): How rarely jobs go badly: share of 1–2★ reviews — 60% the last 24 months (or the 20 newest if fewer), 40% all-time; 0% = 100, 15%+ = 0; the category percentile can only raise it.Craft & service (0%): Google review highlights: Quality, Professionalism, Responsiveness, Punctuality — how rarely reviewers flag them as a negative, per review since highlights began; 0% = 100, 5%+ = 0. Subtracted from the score (up to −10), never averaged in — clean highlights are the norm, not a bonus.Value (14%): Customers’ own price verdicts (Great / Reasonable vs Overpriced) and Value highlights; 65% absolute (all “reasonable” ≈ 80, “great” = 100), the category percentile can only raise it.Momentum (0%): Penalises only a real slide: last-12-month average below lifetime (−0.5★ = 0). Still 4.8★+ over the last year, or steady/improving = 100. Subtracted from the score (up to −10), never averaged in.Replies to reviews (7%): How often the owner publicly replies to reviews under 5★ (1–4★). Needs 3+ such reviews, otherwise not counted; 65% absolute (80%+ replied = 100), the category percentile can only raise it.One letter per factor score: A = 80+, B = 60–79, C = 40–59, D = 20–39, F = below 20. | ★Google star rating as shown on Google Maps. | Typical billMedian bill customers of this company reported in their reviews (needs 3+ priced reviews). |
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| 1 | A 100How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%100+58.7Reliability 26%99+25.8Value 15%100+15.2Experts Score= 100Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AA–AA– | 5.00 | — | |
| 2 | A 100How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%100+58.7Reliability 26%100+26.1Value 15%100+15.2Experts Score= 100Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 5.00 | — | |
| 3 | A 100How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%100+58.7Reliability 26%99+25.8Value 15%100+15.2Experts Score= 100Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 5.00 | — | |
| 4 | A 100How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%100+58.7Reliability 26%99+25.8Value 15%100+15.2Experts Score= 100Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 5.00 | — | |
| 5 | A 100How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 69%100+69.2Reliability 31%99+30.5Experts Score= 100Not enough data for value, replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AA––A– | 5.00 | — | |
| 6 | A 99How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%99+54Reliability 24%99+24Value 14%100+14.1Replies to reviews 7%94+6.6Experts Score= 99Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAA | 4.98 | — | |
| 7 | A 99How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%99+58.1Reliability 26%98+25.6Value 15%100+15.2Craft & service penalty99−0.1Experts Score= 99Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 4.99 | — | |
| 8 | A 99How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%99+58.1Reliability 26%98+25.6Value 15%99+15.1Craft & service penalty99−0.1Experts Score= 99Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 5.00 | — | |
| 9 | A 99How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%99+58.1Reliability 26%98+25.6Value 15%100+15.2Craft & service penalty99−0.1Experts Score= 99Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 5.00 | — | |
| 10 | A 98How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%98+57.5Reliability 26%98+25.6Value 15%100+15.2Craft & service penalty99−0.1Experts Score= 98Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAA–– | 4.99 | — | |
| 11 | A 98How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%98+53.5Reliability 24%99+24Value 14%100+14.1Replies to reviews 7%94+6.6Experts Score= 98Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAA | 4.98 | — | |
| 12 | A 98How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%100+54.5Reliability 24%99+24Value 14%100+14.1Replies to reviews 7%73+5.2Experts Score= 98Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAB | 4.99 | — |
What jobs cost
What customers paid, from the price Google asks reviewers to report.
| Job | Low25th percentile: 1 in 4 customers paid less than this. | TypicalMedian of the bill customers reported in their Google review (Google asks reviewers for a price range; we use the middle of each range). | High75th percentile: 1 in 4 customers paid more than this. | FairOf customers who rated the price, the share who chose “Great price” or “Reasonable” rather than “Overpriced”. |
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Mold Inspectors at a glance
How the 61 mold inspectors we rated compare, and what customers praise most.
Experts Score grades
A = score 80+, F = below 20.
- Grade A5692%
- Grade B47%
- Grade C12%
- Grade D00%
- Grade F00%
Google ratings
Average stars per company.
- 4.90★ and up4980%
- 4.80–4.89★1118%
- 4.60–4.79★12%
- Below 4.60★00%
What customers praise
Share of Google review highlights.
- Quality5,32224%
- Professionalism5,82626%
- Responsiveness4,92022%
- Punctuality2,40211%
- Value4,09318%
Was the price fair?
All price verdicts left with reviews.
- Great price59442%
- Reasonable74353%
- Overpriced161%
- Not sure483%
Price verdicts by year
Share calling it great / reasonable / overpriced.
How we grade
Satisfaction (54%) — Recency-weighted star average (2-year half-life), shrunk toward the category mean by review volume; the company’s own lifetime average as the prior; absolute: 4.0★ = 0, 5★ = 100.
Reliability (24%) — How rarely jobs go badly: share of 1–2★ reviews — 60% the last 24 months (or the 20 newest if fewer), 40% all-time; 0% = 100, 15%+ = 0; the category percentile can only raise it.
Craft & service (penalty, up to −10) — Google review highlights: Quality, Professionalism, Responsiveness, Punctuality — how rarely reviewers flag them as a negative, per review since highlights began; 0% = 100, 5%+ = 0. Subtracted from the score (up to −10), never averaged in — clean highlights are the norm, not a bonus.
Value (14%) — Customers’ own price verdicts (Great / Reasonable vs Overpriced) and Value highlights; 65% absolute (all “reasonable” ≈ 80, “great” = 100), the category percentile can only raise it.
Momentum (penalty, up to −10) — Penalises only a real slide: last-12-month average below lifetime (−0.5★ = 0). Still 4.8★+ over the last year, or steady/improving = 100. Subtracted from the score (up to −10), never averaged in.
Replies to reviews (7%) — How often the owner publicly replies to reviews under 5★ (1–4★). Needs 3+ such reviews, otherwise not counted; 65% absolute (80%+ replied = 100), the category percentile can only raise it.