Plaster and Lath Water Damage in Hammond, IN

Can plaster that got wet be dried and kept?

Often, yes, when the plaster is sound and the readings return to the dry goal. Plaster that has lost its bond to the lath, or that has softened, is removed.

Plaster is more forgiving than many people expect. A base coat that held water for a few days and then dried will often keep its strength, especially on an interior wall where the lath is still tight. The finish coat may need to be patched, and the paint will need to be redone, but the wall itself stays.

The test is whether the plaster still holds to the lath. A soft spot that gives under a fingertip, a bulge that moves, or a crack that opens wider after drying is a sign the bond has failed. Those areas are removed and the lath behind them is dried before any new plaster goes on.

Why does old plaster hold water for so long?

The base coat is thick and dense, and the air space behind the lath is small. Water that gets in does not leave quickly, and it can stay for weeks in a closed wall.

A plaster base coat of the older type was built in several layers, each of them with its own water content. Once that water is in, it moves slowly, and it is absorbed by the lath and the stud behind. The surface can dry in a day while the coat behind it stays wet for a week or longer.

The house's age also matters. Balloon framing and wide plank subfloors leave long, open cavities behind the walls, and water can travel along them to a floor or a room further from the leak. The readings are taken across the cavity, not only where the stain is.

What should be photographed and kept before any plaster is removed?

The wall or ceiling should be photographed before anything is opened, and each opening should be recorded with its location and the reading that prompted it.

A plaster record is the evidence of what the wall looked like at the start and what it looked like after drying. Photographs from several angles, a note of the readings and a sketch of the openings give the insurer and the repair contractor what they need to make decisions without repeating the work.

Keep any plaster or lath that was removed until the insurer has seen it or has said in writing that it can go. If it is sent to a skip, the record should say where and when.

Lath that is still sound after drying is cleaned of loose plaster and sealed where the wall is to be closed, which gives the new coat a firmer key. The sealing is done only once the readings are dry, because sealing a damp lath traps moisture behind the new finish.

How is plaster repaired once it is dry?

Repair is a separate stage. Plaster patching, skim coating or board replacement is quoted by the trade that does that work, after the drying readings are complete.

A small area of lifted plaster is often patched by a plasterer, and a larger area may need the lath replaced and the base coat rebuilt. Where drywall is used to replace plaster, the boards are fixed to the framing and taped, and the paint is matched to the surrounding wall. The restoration record says which areas were dried and which were removed.

A repair is best done after the readings have been dry for the full period in the plan. Closing a wall early is the most common reason plaster cracks again within the first year.