What a Drying Log Is and Why You Should Ask for One

A water damage drying log is the written record of a drying job: the moisture readings in the wet materials and the temperature and humidity of the air, taken every day until everything is dry. It is the only real proof that drying was completed, since dry cannot be confirmed by looking or touching. Ask for one before the work starts, and ask for a copy when it ends.

What a water damage drying log contains

Formats vary, but a proper log has the same parts.

• Job details: the address, the date and cause of the loss, the type of water involved and when drying began.
• A sketch or list of the affected areas: which rooms, which walls, how far the water travelled.
• Fixed reading locations: numbered points on that sketch, such as the bottom plate on the north wall of the kitchen or the subfloor at the dishwasher, so the same spots are tested every visit.
• Material readings: the moisture reading at each point, each day, with the material and the meter used.
• The dry standard: readings from the same materials in a part of the house that did not get wet. This is the target.
• Air readings: temperature and relative humidity in the affected area, in an unaffected part of the house, outdoors and at the outlet of each dehumidifier.
• Equipment: how many dehumidifiers, air movers and other machines, where they are, and the dates each was placed and removed.
• Date, time and who took the readings.

Photos usually go with it: the damage on the first day, the meter on the material at key points, and the same spots on the last day.

Why it matters to you

Without a log, the end of a drying job is someone's opinion. With one, it is a set of numbers anyone can check.

• It proves the job was finished. Final readings at or below the dry standard are the difference between dried and looked dry.
• It protects you against mold later. If a problem shows up in six months, the log shows what was wet, what was dried and to what level.
• It supports an insurance claim. Adjusters want to see that the equipment and the number of days were justified. Daily readings do that.
• It helps when you sell. A leak that was professionally dried and documented is a much easier conversation with a buyer or home inspector than a stain with no paperwork.
• It keeps the contractor honest about time. Equipment should stay as long as the readings require and no longer. A log shows both.

How to read one

You do not need training to follow a drying log. Look for three things.

First, the trend. Material readings should fall each day. The first day or two may show small drops, then steeper ones. A point that has not moved in two or three days is a flag. It usually means water is trapped behind something, or there is a source still feeding it.

Second, the comparison. The readings at the end should match the dry standard taken in the unaffected area. For wood framing, our own target is under 16 percent moisture content.

Third, the air. The air in the drying area should get drier day by day, and the air leaving each dehumidifier should be drier than the air going in. Many logs show a figure called grains per pound or humidity ratio, which is the actual amount of water in the air. Lower is drier. If the affected area stays as humid as outdoors, something is letting outside air in or there is not enough dehumidification.

Signs of a weak or missing log

• No readings at all, just a count of equipment and days.
• Readings on only the first and last day.
• Numbers with no locations, so nobody can tell what was tested.
• No dry standard, so there is nothing to compare against.
• Every point dropping by the same neat amount every day. Real materials do not dry that evenly.
• Equipment removed while some points were still above target, with no note explaining why.
• Reluctance to hand over a copy.

What we provide

We take and log readings every day of a drying job. When it is done you receive a clearance report with the readings, before and after photos and an itemized invoice. Customers pay us directly, and that package is what you would submit to your insurer if you are making a claim. Whether and how a claim is paid is between you and your insurer, so check with your adjuster or broker about what they need.

Keep the log with your house papers, the same way you would keep a furnace receipt or a roofing invoice. It costs nothing to store and is hard to recreate later.

If a crew is drying your home right now, ask to see today's readings. A contractor who is keeping a proper log can show you on the spot.

Common questions