Structural Drying in Franklin, TN

What a moisture reading is and is not

A reading is a comparison, and it means something only against the dry material nearby.

A pin meter pushes two small probes into the material and reads its electrical resistance, which rises as the material dries. A pinless meter reads the surface without marking it. Neither gives a true percentage of water for every material, so the crew compares the wet reading with a reading taken in a dry part of the same material, such as the framing in a room that was not touched.

The readings are written down with their location, so the progress can be compared from day to day. A reading that is lower than the day before is progress; a reading that climbs again means the source has not been stopped.

How the house is kept closed during drying

Air that leaks in from the rest of the house weakens the work.

• Keep the doors of the drying rooms closed, and close the supply and return vents in those rooms.
• Place the dehumidifier's exhaust where it will not blow back into the same room.
• Keep the outside doors shut except for the crew's entry and exit.
• Remove or cover rugs and furniture that will hold moisture, and move them out of the air path.
• Tell the crew before any room is opened or used, so the readings are not disturbed.

Why humid summers change the job

The equipment works harder when the outside air is already full of water.

A dehumidifier pulls moisture out of the air it is given. In a humid summer the air arriving at the house has more moisture to give up, so the unit runs longer and the readings fall more slowly. The crew plans for that by checking the readings more often and by setting the equipment to the room rather than to a fixed schedule.

The crew reads the room conditions each day and does not assume the pace of the drying from one week to the next.

What the homeowner will notice during the drying

The equipment is loud, warm and steady, and the house will feel different for several days.

Air movers run with a steady hum, and dehumidifiers collect water in a tank or drain it to a hose. The room being dried is warmer than the rest of the house, and the air can feel close. The household should expect a damp smell at first that fades as the readings drop.

The homeowner should not move the equipment or switch it off. A machine turned off early, or moved to a different room, can leave a zone to dry on its own, and the readings will show the setback the next morning.

When the equipment comes off

The equipment is removed when the readings match the dry rooms, and not before.

The last readings are compared with the dry rooms beside each zone. When every zone reads at that level and has held there for a day, the crew walks the house with the homeowner, shows the readings and removes the equipment. The cavity openings are closed with their reasons written in the record.

The file handed over at the end is the daily readings, the map, the photographs and the equipment log. An insurer or a builder will ask for it, and it is much easier to keep than to reconstruct.

Equipment that is set and then left alone is the most common reason a drying runs longer than the readings predicted. A dehumidifier that has filled its tank and stopped is logged as a stop, not as a finished zone. The crew checks the equipment log against the readings each morning, and a stop that went unnoticed overnight is written into the record so that the next day's readings are read with it in mind.