Hidden Mold Behind Walls in Provo, UT

The musty smell with no visible mold

Hidden mold is the hardest problem to see and the easiest to smell. The wall looks fine, the ceiling looks fine, and the room smells musty — usually in the morning, when the room has been closed all night. The growth is behind the drywall, under the flooring, or in a space you cannot see into, and the smell is the only sign that reaches the room.

The wall cavity is the most common hiding place in Utah County. A finished basement has a cavity between the drywall and the foundation wall, and warm indoor air meets the cold concrete there. Condensation forms, the paper facing of the drywall stays damp, and the growth follows. The cavity is behind a wall that looks fine from the room, so the smell is the first sign — and sometimes the only sign for months.

Other hiding places follow the same pattern: under flooring after a leak, behind a bathroom wall after a shower leak, in a closet against an outside wall, and in the space behind a built-in cabinet. Each one is a place where moisture sits out of sight, and each one is found the same way — by the inspection, not by looking at the room.

How the inspection finds hidden mold

The inspection finds hidden mold with moisture readings, not with the eye. The provider takes readings through the drywall at several heights, and follows the readings to the wettest spot. A wall that reads wet at the bottom and dry at the top points to a leak or to condensation in the cavity. A wall that reads wet in one place and dry everywhere else points to a pipe or a window in that spot.

Where the readings are high, the drywall is opened — usually a small section — so the cavity can be seen and the extent of the growth measured. Air sampling is sometimes used too, where the growth cannot be seen even after the wall is opened. The provider explains what was found and what the plan covers before any work starts, and the inspection report is the record of what was found.

A bedroom that smells musty every morning

Hidden mold in Utah County homes

Hidden mold in Utah County is usually a basement story or a bathroom story. The basement story is the finished basement wall cavity, where condensation forms on the cold foundation wall. The bathroom story is the wall behind the tub or the shower, where a slow leak puts water into the cavity over months. Both are found by the inspection, and both are dealt with by opening the wall, removing the affected material, and drying the cavity.

It is also a rental story. Provo has about 114,500 residents and only about 29 in 100 homes are owner-occupied, which means a large share of the housing stock is rented. In a rental the tenant smells the mold and the landlord cannot see it, and the inspection report becomes the document both sides need. The landlord and tenant guide explains who pays and what the inspection covers.

What not to do with hidden mold

Do not paint over a stain or a damp patch. Paint hides the growth and does nothing about the moisture behind it, and the growth returns through the paint. Do not ignore a musty smell because the wall looks fine — the smell is the sign, and the growth is behind the wall. Do not open a large section of wall yourself: disturbing the growth can release spores into the air, and the cavity should be opened by the provider, with containment where it is needed.

Leave the wall in place, note where the smell is worst and when it started, and call now to arrange an inspection. The inspection finds the moisture source, and the plan follows from what it finds.