# May Indoor Air Investigations

**Trade:** Home Inspection · **Address:** 3 Tolkien Ln, Tyngsborough, MA 01879 · **Phone:** (978) 649-1055 · **Website:** http://www.mayindoorair.com/ · **Languages:** English

**Rating: 4.2/5** (medium confidence) — from 20 reviews across 5 sources.
100% of sentiment-scored reviews read net-positive. Last 6 months: 1 reviews, 0 negative.

## The honest read

May Indoor Air Investigations is who Massachusetts homeowners call when something in the house is making them sick and nobody can say why. The Tyngsborough firm is run by founder Jeffrey C. May, its principal scientist, with co-owner Connie L. May managing the office, and the company says it investigates mold, odors, VOCs, moisture and leak problems across Massachusetts and New England — analyzing its own air and dust samples by microscopy rather than sending everything to an outside lab.

The review history is long and runs one direction. HomeAdvisor shows 4.9 stars across 52 reviews, 94 percent of them five-star, and lists 34 years of experience; the small Google page is a straight 5.0. The stories are strikingly consistent: in a 2021 review, a homeowner who had spent six years tearing out roof, walls and ceilings chasing a recurring problem said May found it — plus several more urgent issues — in one visit. A 2017 customer described a five-hour investigation with about fifteen samples taken; another that year had the full written report in their inbox the same evening.

What customers keep singling out is the business model itself. May inspects and diagnoses but does not sell remediation — a 2025 reviewer, wary of being upsold, noted that the report told them exactly what did and did not need fixing, and a 2016 customer hired the firm precisely because it had no stake in finding damage. The reports draw repeated praise too: room-by-room findings with photographs and photomicrographs, plus prevention and repair advice. A 2015 reviewer mentioned May has written four books on mold and got a copy at the inspection.

The thing to budget for is the bill. "He isn't cheap," a 2021 reviewer allowed, and a 2017 customer admitted nerves about the cost before concluding it was worth every penny — so pin down scope and fee when you book. This is the right call for allergy and asthma sufferers, buyers weighing a musty house, or anyone who wants an independent diagnosis before paying a remediation crew.

**Strengths:**
- Diagnosis-only model — inspects and tests, sells no remediation
- Detailed reports — photographs, photomicrographs, and repair recommendations
- Deep review history — 4.9 across 52 HomeAdvisor reviews since 2015
- Whole-house thoroughness — multi-hour, room-by-room investigations with sampling
- Published expertise — founder authored four books on indoor air quality

**Concerns:**
- Premium pricing — reviewers call it costly but worth it

## Claims & citations

Every claim below is backed by real evidence rows — uncited claims are dropped in code before publication.

- Tyngsborough, MA building and indoor air quality consultancy performing mold inspections and testing, odor and VOC testing, moisture and leak investigations, and dust-sample microscopy across Massachusetts and New England _(confidence: high)_
  - [Official Website](http://www.mayindoorair.com) — “May Indoor Air Investigations LLC is a Tyngsborough, MA based building and indoor air quality consultancy that performs mold inspections and…”
  - [Official Website](http://www.mayindoorair.com) — “Stated service area (self-reported): Boston, Cambridge, Concord, Sudbury, Lexington, Chelmsford, Tyngsborough, Hudson, Worcester, Northampto…”
- Founded by Jeffrey C. May, principal scientist; Connie L. May is co-business owner and office manager, per the company's own site _(confidence: high)_
  - [Official Website](http://www.mayindoorair.com) — “Ownership (self-reported): Founded by Jeffrey C. May, principal scientist; Connie L. May is co-business owner and office manager”
- HomeAdvisor shows 4.9 stars across 52 reviews (94% five-star) and lists 34 years of experience; Google shows 5 stars from 4 ratings _(confidence: high)_
  - [Google](https://www.google.com/maps/search/?api=1&query=May%20Indoor%20Air%20Investigations%20LLC&query_place_id=ChIJq6qqqhq744kR0eKxleTyyPk) — “Google: 5★ from 4 ratings”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “HomeAdvisor: 4.9★ from 52 ratings”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “HomeAdvisor star distribution: 94% 5★ · 6% 4★ (of 52 ratings)”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “HomeAdvisor profile for May Indoor Air Investigation LLC of Tyngsboro, MA showing a 4.9-star average across 52 reviews (94% five-star), 34 y…”
- Diagnosis-only model repeatedly valued by customers — the firm tests and diagnoses but does not sell remediation, so reports carry no upsell _(confidence: high)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sCi9DQUlRQUNvZENodHljRjlvT21SRFoxQlBNVlpKZVhkQmJtTmtkMHhVU0hONVZrRRAB!2m1!1s0x0:0xf9c8f2e495b1e2d1!3m1!1s2@1:CAIQACodChtycF9oOmRDZ1BPMVZJeXdBbmNkd0xUSHN5VkE%7C%7C?hl=en) — “5★ Our contractor recommended Jeff after confirming for me that many mold remediation companies are selling fish oil. I’m allergic to mold a…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Like many others we had ice dam issues over the last few years. After making repairs to outside, we were finally ready to paint the inter…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ We had been away and returned to find an alarming, musty smell in the house. After several days we were able to narrow the source to a ba…”
- Multi-hour, room-by-room whole-house investigations with detailed written reports including photographs and recommendations, described in reviews from 2015 through 2018 _(confidence: high)_
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Dr. May spent several hours at our house, carefully explaining his process and setting up his sampling equipment. He went room by room an…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ I called several companies to find out who would best suit my needs. Jeff May was head and shoulders the most responsive, kind and thorou…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Jeff is fantastic and extremely knowledgeable about indoor air quality. I was very nervous about spending so much money on an indoor air …”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Results were as expected: presence of mold and need for clean-up. Jeff was very thorough in explaining what he found, what implications w…”
- A 2021 reviewer said May found a problem they had chased for six years, along with more urgent issues, in one visit _(confidence: medium)_
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ The Mays were amazing, completely in a different league than anyone I've ever dealt with to do with anything home/inspection issues. This…”
- States certifications including Certified Indoor Air Quality Professional (AEE) and Council-Certified Microbial Consultant (ACAC); HomeAdvisor also lists Certified Mold Inspector and Assessor (ESA) _(confidence: medium)_
  - [Official Website](http://www.mayindoorair.com) — “Stated certification/affiliation: Certified Indoor Air Quality Professional, Association of Energy Engineers”
  - [Official Website](http://www.mayindoorair.com) — “Stated certification/affiliation: Council-Certified Microbial Consultant, American Council for Accredited Certification”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “Listed certification: Certified Indoor Air Quality Professional (AEE)”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “Listed certification: Certified Mold Inspector and Assessor (ESA)”
- A 2015 reviewer noted Jeffrey May has written four books on mold and indoor air quality _(confidence: medium)_
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Jeff is extremely knowledgeable and a mold industry expert (he's written 4 books on mold and gave me a copy of one at the inspection). He…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Jeff May if fantastic. He is thorough and very knowledgabe. He will also provide you a copy of his book "My home is killing Me!" Great re…”
- Cost runs high — a 2021 reviewer said the service isn't cheap and 2017 customers described weighing a significant flat fee, though both judged it worthwhile _(confidence: medium)_
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ The Mays were amazing, completely in a different league than anyone I've ever dealt with to do with anything home/inspection issues. This…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ I called several companies to find out who would best suit my needs. Jeff May was head and shoulders the most responsive, kind and thorou…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Jeff is fantastic and extremely knowledgeable about indoor air quality. I was very nervous about spending so much money on an indoor air …”
- Mold, indoor air quality and odor testing with air and dust sample analysis, thermal imaging, VOC and formaldehyde testing, and carbon monoxide and gas leak testing _(confidence: high)_
  - [Official Website](http://www.mayindoorair.com) — “May Indoor Air Investigations LLC is a Tyngsborough, MA based building and indoor air quality consultancy that performs mold inspections and…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “Services offered (HomeAdvisor): Complete Home Inspection, Ceiling Fan Installation, Ceiling Fan Repair, Mold, indoor air quality and odor te…”
- Specializes in Home Inspection _(confidence: high)_
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “5★ Dr. May spent several hours at our house, carefully explaining his process and setting up his sampling equipment. He went room by room an…”
  - [Official Website](http://www.mayindoorair.com) — “May Indoor Air Investigations LLC is a Tyngsborough, MA based building and indoor air quality consultancy that performs mold inspections and…”
  - [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html) — “Services offered (HomeAdvisor): Complete Home Inspection, Ceiling Fan Installation, Ceiling Fan Repair, Mold, indoor air quality and odor te…”

## License

No license record has been checked yet for this contractor.

## Sources

- [Google](https://www.google.com/maps/search/?api=1&query=May%20Indoor%20Air%20Investigations&query_place_id=ChIJq6qqqhq744kR0eKxleTyyPk): 5.0★ from 4 ratings
- [Google Reviews](https://www.google.com/maps/search/?api=1&query=May%20Indoor%20Air%20Investigations&query_place_id=ChIJq6qqqhq744kR0eKxleTyyPk): Listed on this source
- [Yelp](https://www.yelp.com/biz/may-indoor-air-investigations-tyngsborough-2): Listed on this source
- [Official Website](http://www.mayindoorair.com): Self-reported profile and service details
- [HomeAdvisor](https://www.homeadvisor.com/rated.mayindoorairinvestigationllc.153128725.html): 4.9★ from 52 ratings

## Recent reviews

- **5/5 · Google Reviews · Marjie McDaniel · 2026-08-18**: Jeff is so knowledgeable. I was in a panic about the mold test results I had done (and AI was not helpful). He explained what I was dealing with, how to mitigate it, and answered all my questions.  I highly recommend him!
- **5/5 · Google Reviews · Anna Soloway · 2025-10-31**: Our contractor recommended Jeff after confirming for me that many mold remediation companies are selling fish oil. I’m allergic to mold and needed a plan for our new home, but was worried about being taken advantage of. Jeff doesn’t sell remediation. He came in, did a thorough and incredibly thought…
- **5/5 · Google Reviews · Catherine Loeb · 2025-03-13**: We recently hired Jeff and Connie May of May Indoor Investigations to help us identify environmental factors in our house that might be contributing to health concerns.

Knowing absolutely nothing about this field, we had no idea where to turn for reliable help.  However, the Mays came highly recomm…
- **5/5 · HomeAdvisor · Galine P. · 2023-02-01**: If it would be possible I could give more than 5 stars. Jeff and Connie are very nice people and incredibly knowlegable specialists. They went above and beyond, conducting inspection of our house. I invited them because of presence of mold and odors. The house was thoroughly inspected not only for t…
- **5/5 · Google Reviews · Roger Hankey · 2021-11-13**: Jeff kindly responds to questions from other home inspectors. His newsletter is also quite helpful.
- **5/5 · HomeAdvisor · Brian F. · 2021-02-01**: The Mays were amazing, completely in a different league than anyone I've ever dealt with to do with anything home/inspection issues. This was a problem that every year for 6 years I would be ripping out the roof, walls, windows, and ceilings and replacing them trying to chase down the problem. Dr Ma…
- **5/5 · HomeAdvisor · David S. · 2018-08-01**: Dr. May spent several hours at our house, carefully explaining his process and setting up his sampling equipment. He went room by room and explained what he was looking for and pointing out areas where he saw suspect mold or other issues. He followed up approximately a week later with a multi-page r…
- **5/5 · HomeAdvisor · Jessica V. · 2017-08-01**: From setting up the appointment with Connie to receiving the final report, everything was handled professionally, courteously, and expeditiously. We received an email confirming our appointment with detailed instructions for how to best prepare our home for the inspection. Jeff arrived precisely on …
- **5/5 · HomeAdvisor · Lindsay R. · 2017-07-01**: I called several companies to find out who would best suit my needs. Jeff May was head and shoulders the most responsive, kind and thorough. He talked to me at length about things I could do for the overall health of my home and listened patiently to all of my questions. When I contracted his servic…
- **5/5 · HomeAdvisor · SHREE T. · 2017-06-01**: We called Mr. May on the recommendation of our home inspector, in order to inspect the basement insulation. Basement insulation appeared discolored and the basement was damp, so we suspected mold, and wanted to know the extent of the mold contamination. Jeff arrived on time, took air samples from th…

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Data freshness: last scanned 2026-08-28T01:34:11.245Z.
Cite as: May Indoor Air Investigations — Tavlee (https://tavlee.com/contractor/may-indoor-air-investigations-tyngsborough)
Source: https://tavlee.com/contractor/may-indoor-air-investigations-tyngsborough