Found Mold in Your Massachusetts House? Here's What to Do
Mold grows wherever moisture sits, so the real fix is stopping the leak or dampness first and then cleaning or removing what's affected. Massachusetts guidance follows the EPA rule of thumb: a patch under about 10 square feet is usually a DIY job, and anything bigger should go to a professional. Massachusetts does not license mold remediation companies, so vetting the contractor is on you.
What to look for
- Musty or earthy smell, especially in basements and closets
- Black, green or white spotting on walls, ceilings, or around windows
- Peeling paint, water stains, or warped drywall
- Condensation on windows or pipes and high indoor humidity
- Recurring allergy-like symptoms that ease when you leave the house
What it costs
| What | Typical cost | Source |
|---|---|---|
| Mold remediation (national average) | $1,223 to $3,757; average about $2,368 | angi.com |
| Basement mold remediation (national average) | $500 to $3,000 | angi.com |
| Whole-house mold remediation (national average) | $10,000 to $30,000 | angi.com |
| Mold testing (national average) | $250 to $350 | angi.com |
Ranges are published estimates; your quote depends on the house. Get two or three written quotes.
Massachusetts rules to know
- Massachusetts does not require a license to do mold remediation; the state suggests checking credentials such as IICRC, AIHA or ACAC membership, references, and the BBB (source: mass.gov)
- State guidance says mold testing is generally not needed and there are no federal or state standards for a 'safe' amount of mold; visible mold should simply be cleaned up (source: mass.gov)
- For rentals, the State Sanitary Code (105 CMR 410, updated 2023) requires homes to be watertight and free from excess moisture or the appearance of mold, and wet surfaces to be dried within 48 hours after a leak or flood (source: eli.org)
- Under the Sanitary Code, a board of health inspector does not need environmental testing to cite mold or excess moisture (source: eli.org)
- Massachusetts has no specific mold disclosure form for sellers, but sellers may not lie about or actively conceal known problems when a buyer asks (source: nolo.com)
Who to call
- A mold remediation company with IICRC or similar certification; since there is no state mold license, check whether they hold a Home Improvement Contractor registration for any rebuild work (source: contractorhub.mass.gov)
- A licensed plumber or roofer to fix the water source; check plumbers at the state eLIPSE lookup (source: occupationallicensingandpermitting.mass.gov)
- Tenants: your city or town board of health can inspect under the State Sanitary Code
- If you have breathing problems or health concerns, see a doctor
DIY or hire a pro?
You can usually clean a small area (under about 10 square feet) on hard surfaces yourself with gloves, eye protection and an N95. Larger areas, mold inside walls or HVAC ducts, or anyone with asthma or a weak immune system in the home means you should hire a pro.
If fixing it is more than you want to take on
If the mold is from an old, fixed leak, cleaning it and listing normally usually gets the best price. If the moisture source is a big problem (foundation, roof, grading), you can sell as-is on the open market and answer buyer questions honestly, or sell as-is to a cash buyer. A cash buyer is faster and skips the repairs, but will pay less than the house would bring after remediation.
Want a cash offer on the house as it is?
Western Mass Cash Home Buyers buys houses as-is across Western Massachusetts: no repairs, no cleanout, no fees. You pick the closing date.
Common questions
Do I have to disclose mold when selling a house in Massachusetts?
Massachusetts has no required mold disclosure form, but you cannot lie or hide a problem if a buyer asks about it. When in doubt, disclose and ask a real estate attorney.
Is mold testing worth it in Massachusetts?
State guidance says testing usually isn't necessary because there are no safe-level standards; if you can see or smell mold, clean it and fix the moisture.
Do mold removal companies need a license in Massachusetts?
No. Massachusetts does not license mold remediation, so check certifications like IICRC, references and reviews before hiring.
Can my landlord ignore mold in my apartment?
No. The State Sanitary Code requires rentals to be free of excess moisture and the appearance of mold. Call your local board of health to request an inspection.
How much does mold removal cost?
Nationally most jobs run about $1,200 to $3,800, with basements often $500 to $3,000 and whole-house jobs $10,000 or more.
Related guides: Asbestos · Lead paint · Radon · Termites & pests · Foundation problems · Roof replacement · all house problem guides
Sources
Checked September 2026: angi.com · mass.gov · eli.org · nolo.com · nolo.com · contractorhub.mass.gov · mass.gov · mass.gov
General information, not legal, tax, medical or engineering advice. Rules and prices change; confirm with the agency or a licensed professional.