Rot, Mold and Leaks Found During Demolition: What Happens Next

The first day of demolition is when a bathroom remodel learns the truth about the house. Water that has been escaping a shower pan, a toilet seal or a tub drain for years does its damage out of sight, and tile and drywall can look sound right up to the moment they come off. Planning for that possibility, in the budget and in the contract, keeps a discovery from turning into a dispute.

What demolition commonly uncovers

The warning signs before demolition are worth noting: a floor that flexes near the toilet or shower, loose or hollow-sounding tile, cracked grout that keeps coming back, stains on the ceiling below, a toilet that rocks, and a persistent musty smell. Each one makes a finding more likely, though none tells you how far the damage goes.

What the code requires once it is found

Damage found during a permitted remodel is not optional to fix. Washington's residential code for existing buildings requires that unsafe structural elements uncovered during the work be repaired (IRC R4502.2.1, WAC 51-51-4502). In practice, that means rotted subfloor is cut out and replaced, damaged joists are repaired or sistered, and wet framing is dried or replaced before anything is closed up. If the repair changes the approved plans, the permit office may need to review the change before work continues past that point.

Inspections also matter here. Framing, plumbing and other work intended to be covered must be inspected before it is concealed, so repaired structure is normally seen by the inspector. See bathroom remodel inspections.

Mold found behind the walls

Mold under a shower or behind a tub surround is common in a bathroom that has leaked. The guidance from the EPA and Washington's Department of Health (DOH) is consistent on the essentials:

• Fix the water first. "The key to mold control is moisture control" (EPA). Cleaning mold without stopping the leak only buys time.
• Size matters. The EPA says most people can handle an area under about 10 square feet themselves. DOH defines a small area as "less than about ten square feet, or a patch three feet by three feet square," and recommends hiring a professional for larger areas, for mold contaminated by sewage, or for mold "in hidden places."
• Testing is usually unnecessary. DOH: "You don't need to sample for mold because in most cases you can see or smell mold."
• Remove what cannot be cleaned. Moldy porous materials such as drywall and insulation are cut out and replaced. Hard surfaces can be cleaned; DOH describes washing with a mild detergent solution such as laundry detergent and warm water.
• Dry everything. The EPA advises drying water-damaged areas within 24 to 48 hours to prevent new growth.

DOH also notes that Washington has no specific certification requirement for mold or water damage restoration, so anyone can call themselves a mold specialist; ask about training and methods. More detail is on mold in bathrooms.

How a written change order handles it

A change order is a written amendment to your contract that describes added or changed work and its effect on price and schedule. L&I advises homeowners to get changes in writing, to "Avoid verbal contracts or amendments," and to make sure the contract spells out "Warranties and processes for change orders."

For hidden damage, a good change order:

1. describes what was found, ideally with photos;
2. describes the repair, such as the area of subfloor or the framing to be replaced;
3. states the added cost, or how it will be calculated;
4. states any effect on the schedule;
5. is signed by you before the added work proceeds, except where something must be made safe right away.

At JDI, the bathroom planning ranges do not include unexpected structural repair found inside walls, which JDI handles by written change order. The kitchen guide covers change orders and contract terms in more depth in contracts, deposits and change orders, and our bathroom page on contracts and change orders covers the bathroom-specific clauses.

Budgeting a contingency

Because hidden damage is common in older bathrooms and impossible to price in advance, set aside a contingency that is not committed to finishes. There is no single right amount. Size it with your contractor based on:

• the age of the house and of the current bathroom;
• warning signs you already see, such as soft floors, stains below, loose tile or a musty smell;
• whether the floor is reachable from a crawl space or ceiling below for a look before demolition;
• how much of the room is being opened; a full gut exposes more than a fixture swap.

If you do not need the contingency, it can go toward an upgrade near the end of the job, after the risky phase is over.

When insurance is part of the picture

If the damage came from a sudden event, such as a burst pipe, some of it may be an insurance claim. The Washington Insurance Commissioner explains that most homeowners policies cover sudden water damage reported quickly, but not gradual leaks that continued for a long time, and that mold coverage is usually limited to mold resulting from a covered loss. See water damage and homeowners insurance.

Talk to us before demolition day

If you already see signs of damage, tell your contractor during the consultation so the plan and the contingency reflect it. JDI's free in-home consultation ends in an itemized plan, and the firm written quote follows. To start, request a consultation or see our bathroom remodeling service in Vancouver.