How to check if your home is dry after water damage

Room humidity and the condition of a wall

After a dehumidifier has been running, the air and the wetted structure need different checks. A hygrometer measures relative humidity in the air. A moisture meter examines a material within the limits of its sensor. A normal reading on the first instrument does not establish that the inside of a wall has dried. [3]

EPA advises against closing wet wall cavities or applying paint or sealant until the materials are dry inside. A surface that looks dry is not enough evidence to begin refinishing. [1]

What the number on a moisture meter means

Look for the instrument and measurement scale alongside each reading in the report. Wood moisture content, WME and a relative index describe different measurements.

The Protimeter MMS3 manual, for example, explains the distinctions between MC, WME and relative readings. Check the manual for the particular instrument used. [3]

In pinless mode, metal below the surface can produce a falsely high signal. Conductive materials and salts can also affect interpretation. An unexpected reading needs investigation; a single number is not enough to confidently label an area wet or dry. [3] [4]

Where was it measured, and compared with what?

A moisture map ties each reading to a location. Inspection points and the boundaries of detected moisture are marked on a plan. Protimeter describes this approach to documenting an inspection. [5]

Ask what was checked at each point: the face of a panel, a wood stud, the subfloor or another layer. Measurement depth depends on the sensor and material. A reading taken on a finish should not be presented as an assessment of the entire assembly. [3]

Illustration of location labels, not a survey or measured drying results. Actual inspection points depend on the building.

If the contractor uses an unaffected area as a reference, ask why it is suitable for comparison. Are the material and measurement conditions comparable? Has that area itself been checked for wetting? These questions help establish the basis for the chosen target.

IICRC's public position statement includes establishing dry standards and drying goals in the initial inspection. Ask for the selected target and its basis to be recorded in the report. [2]

A thermal camera can support the inspection by showing temperature differences and helping identify areas to check. FLIR's procedure follows the search for a suspect area with a moisture-meter measurement. A thermal image alone does not confirm the presence of water. [6]

What to look for in the drying log

Look for successive readings at identified points and a final check. Phoenix DryLINK training materials, for example, separate air and material records and show measurement dates and drying goals. [7]

Use the following checklist when discussing the report with your contractor.

An editorial checklist for reading a report, not a prescribed IICRC form.

If part of a wall or floor could not be checked, discuss it before the assembly is closed. Clarify which conclusions are supported by measurements and which concern inaccessible layers.

Wood, drywall and concrete have different criteria

Before walls are closed and finishes go back

Ask the contractor to walk through the moisture map and explain the outcome for each material checked. Discuss these four points:

1. Has the leak source been addressed, and who verified it?
2. Which materials reached the selected drying target?
3. What was replaced, what was retained and which areas remain unchecked?
4. What further checks are needed before painting or installing flooring?

Keep the log and photographs of measurement points with your repair records. If the area gets wet again, these records can help compare the new inspection with the previous one.

If mold was found or materials contacted contaminated water, completion of drying does not by itself establish that cleaning is complete. EPA treats cleaning, removing unsuitable materials and drying as separate recovery tasks. [1]