What a Moisture Inspection Report Should Include

A moisture inspection report should tell you where the building is wet, how wet, how far it extends and what the likely source is, backed by actual meter readings and photos. It should also state what was not checked and what should happen next. If a report says only that elevated moisture was detected, with no numbers or locations, it is not much use to you, a contractor, a buyer or an insurer.

What a moisture inspection report should include

• The basics: property address, date and time, who did the inspection and who asked for it.
• The reason for the visit, in the client's words. A stain on the dining room ceiling, a musty basement, a pre-purchase check.
• Conditions that day: indoor temperature and relative humidity, outdoor weather, and recent rain or thaw.
• Tools used, including the type of moisture meter and whether a thermal camera was used.
• Every area checked, listed room by room, including the ones that were dry.
• Moisture readings as numbers, each tied to a location and a material.
• A dry reference reading from an unaffected area of the same material, for comparison.
• Thermal images paired with ordinary photos of the same spot, so anyone can see where each was taken.
• A simple sketch or marked-up photo showing the boundary of the wet area.
• Visible conditions: staining, swelling, rot, mold growth, odour.
• The source, or the most likely sources in order, and how that was determined.
• Limitations: areas that could not be reached, and the fact that the inspection was non-invasive if no openings were made.
• Recommendations: what to repair, what needs drying or removal, and what should be rechecked.

How to read the moisture numbers

Two kinds of numbers appear in these reports, and they mean different things. Readings in wood from a pin meter are given as percent moisture content. Framing lumber in a heated, lived-in house normally sits somewhere around the low teens or below. We use under 16% as the target for calling framing dry after a water loss, and readings well above that mean the wood is wet enough to support mold if it stays that way.

Readings on drywall, plaster, concrete and tile are usually relative. The meter gives a number on its own scale, not a true percentage, and it is only meaningful next to a reading from a dry area of the same material in the same house. That is why the dry reference matters. A report that lists a number for a wall without saying what a dry wall read on the same meter leaves you guessing.

Photos, thermal images and the moisture map

A thermal image by itself proves little. A cool patch can be water, missing insulation or a draft. A sound report shows the thermal image, an ordinary photo of the same view, and the meter reading taken on that spot. Together those three establish that the area is wet.

The map is what makes the report usable. It can be a floor sketch or a photo with the wet boundary drawn on it and readings marked at points along it. A plumber uses it to decide where to open. A drying crew uses it to place equipment. If the area is rechecked later, the same points are measured again so the before and after can be compared directly.

Source and limitations

A good report is honest about how certain it is. Sometimes the source is plain: the wet pattern leads straight to a shower valve, and running the shower makes it worse. Sometimes the inspection narrows it to two candidates and recommends a specific next test, such as a plumber's pressure test or a small opening at a marked location. Both are useful findings. A confident claim with nothing to support it is not.

Limitations protect you as well. Non-invasive tools read the surface layers. They cannot rule out moisture deep behind thick tile, under a slab or behind built-in cabinets. If the attic or crawlspace was not entered, the report should say so.

Warning signs of a weak moisture inspection report

• No numbers, only words such as high, elevated or concerning.
• Readings with no location, material or dry comparison.
• Thermal images with no matching photo or meter confirmation.
• No mention of areas that were found dry or areas not inspected.
• A source stated as fact with no reasoning.
• Alarming language about health, or pressure to sign for work the same day.

Using the report

For a repair, hand it to the plumber or roofer so they open the right spot. For an insurance claim, it documents the extent on a known date, though your insurer decides what it accepts. For a real estate deal, it gives both sides facts to negotiate with instead of a vague note about a stain. After drying or mold removal, a clearance report should repeat the same readings at the same points, with before and after photos, to show the area is dry.

Our leak detection and moisture inspections run $249 to $549 and are written to this standard. Whoever you hire, ask to see a sample report before booking and check it against the list above.

Common questions