Maine’s New Rental Mold Law Is in Effect. Now What?

On July 29, most of the laws passed in Augusta this session quietly took effect. One of them changes the ground rules for every landlord in Maine with a damp building. LD 1927, An Act to Add Mold to the Implied Warranty and Covenant of Habitability, became law without the Governor’s signature on January 11, 2026, and per the Maine Legislature, nonemergency laws from this session are now enforceable as of July 29, 2026. If you own rental property and there is mold in a unit right now, this one is about you.

What the law actually says

The full text of Public Law chapter 515 is one page. It adds a single clause to Maine’s warranty of habitability statute: “It is a breach of the implied warranty of fitness for human habitation when a landlord offers for rent a dwelling unit in which there is a leaking event, chronic moisture or humidity conditions outside of the control of a tenant that result in the growth of mold, bacteria or other biological organisms.”

A “leaking event” is defined broadly: a water leak from flooding or a system or structural failure, such as a failure of a roof, window, door, plumbing system, foundation or appliance. The law also lets any municipality adopt stricter standards by ordinance, so Portland or Lewiston could go further on their own.

This did not come out of nowhere. The Maine Indoor Air Quality Council, which pushed the bill, reports that mold in rental units is the number one call it receives from the public, more than 150 calls a year. Tenants now have a named legal pathway, and landlords now have a named obligation.

What changed for you as an owner

Maine tenants already had general habitability protections. What is new is that mold from a leak or from chronic moisture is now spelled out as a breach, and the operative words are “offers for rent.” The moment you list, re-let, or renew a unit with an active moisture condition growing mold, you are exposed. The other phrase that matters is “outside of the control of a tenant.” A bathroom colony that traces to a tenant who never once ran the exhaust fan is a different conversation than a wall that is wet because the window flashing failed.

Two honest caveats. We are a remediation and testing company, not a law firm, and how courts will draw the line on tenant control has not been worked out yet. Lease language and dispute questions belong with your attorney. What we can speak to is the building.

If there is mold in a unit right now

First, find the water. The law is written around the source, not the stain. A leaking event or a chronic moisture condition is the breach; the mold is the evidence. If you clean the growth and skip the repair, you buy the same problem back in six weeks, plus a record showing you knew about it. What a proper repair-first sequence looks like is laid out in our guide to what to do before you hire anyone.

Second, size it honestly. The EPA’s guide to mold and moisture puts the do-it-yourself threshold at about 10 square feet, roughly a 3 by 3 foot patch. Under that, on a hard surface, you or your maintenance person can clean it and correct the moisture. You do not need to hire us for that, and we will say so on the phone. Larger than that, inside a wall cavity, or in ductwork is where containment and negative air matter, and where our mold remediation process earns its keep. Before you collect quotes, read our published Maine remediation cost ranges so you have a number to check bids against.

Third, move fast on fresh water. EPA’s window for drying water-damaged material is 24 to 48 hours. Past that you are not preventing growth, you are cleaning it up.

Fourth, write everything down. Dates, photos, moisture meter readings, the plumber’s invoice, the hygrometer log. Under the new law, a dated record showing you found the source, fixed it promptly, and cleaned up properly is the strongest position an owner can hold. Air samples and lab results from our environmental testing options can anchor that record before and after the work.

Fifth, do not paint over it. We still open up walls and find a colony sealed under two coats of primer. Paint does not kill the organism or dry the wall. It just hides the evidence until it grows through, and it reads badly in any later dispute.

Turnover season is the test

Here is what this looks like in the field. Maine leases cluster around September 1, and a lot of the buildings we walk in late August have been closed up since June. The pattern repeats: blinds down, windows shut, no air moving. The moisture meter pegs on the bottom two feet of an exterior wall behind a dresser, in a spot the outgoing tenant never saw. The smell hits before the flashlight finds it. That unit, offered for rent as-is next week, is exactly the situation the new law describes.

Health effects are the reason the law exists, so keep them in proportion. EPA notes that allergic reactions to mold are common, that mold can trigger asthma attacks in people with asthma who are allergic to it, and that exposure can irritate eyes, skin, nose and throat. A blog cannot tell you why a tenant feels sick, and neither can a landlord. What you control is the moisture.

Walk your units before the new tenants do. If you find something and want a straight answer on whether it is a wipe-down or a wall-opening, Focused Environmental Services is in Gorham and covers greater Portland and southern Maine. Tyler Chandler, our Lead Environmental Specialist, will tell you the truth either way. Call 207-464-8202 or request a free assessment.