[Problems & Solutions] Answers to your toughest pest questions

Moisture Meters

Are there any industry standards on the use of moisture meters?

This is an interesting question. The simple answer is no, there are no industry standards regarding the use of moisture meters. However, that being said, let’s look at what pest management professionals use these devices for (if they’re using them at all).

Having given many presentations on termite control and inspections for wood-destroying organisms, and having been involved in many lawsuits concerning the above, I have to say that the subject of moisture comes up frequently. In addition, some states require moisture readings be taken if certain conditions or issues exist. Then there is a segment of companies in the industry that use moisture meters religiously in their inspections. Many (if not all of these companies) perform moisture remediation, wood rot work, repairs, etc. An additional segment of our industry uses these meters to substantiate a need for a possible borate treatment (i.e., moisture levels being high enough to support fungus growth).

The pest control industry is split on the issue of moisture meter use. I would say that about 40 percent of the companies in the industry use or have used moisture meters. In my home state (South Carolina), that percentage is much higher because the state has requirements in its inspection regulations and wood rot reports and subsequent moisture readings.

Which moisture meter is used is another factor. The "pin" type can be used for reading relative moistures of exposed wood in a structure. The pins are inserted into the wood grain and a reading is produced. These types of moisture meters are fairly simple, straightforward and inexpensive. We use these to get a general idea of what is going on. I say "general idea" because we really do not analyze the wood (i.e., the wood species), as different species of wood will vary in moisture readings. We generally look for "high" levels, which may indicate problems. A general rule is anything higher than 20 percent is considered an "action" level where some moisture problems probably exist, e.g., poor ventilation, leaks, condensation, no soil barrier, etc. Of course, a reading of higher than 28 percent is wood rot territory and most probably serious moisture condensation or leaks exist in the structure.

Another model of moisture meter that is becoming more popular is the "pad type" meter. Two pads on the back of the meter, instead of pins, are used in taking moisture readings on surfaces of wood, plaster, masonry sheet rock and other surfaces. These moisture meters also come in some sophisticated models for reading moisture through foam board, and the devices computerize their findings into files and logs. The advantage of these are that you do not have to leave two little open holes behind. This means you can measure moisture on finished baseboards and window and door jambs. Also, you can detect high humidity related to moisture within wall voids. Some companies that use other devices like infrared cameras, dogs and other termite detection devices use moisture meters to document or verify findings.

But the question is, although there are no standards regarding the use of moisture meters, should there be? In states that require some "readings" to support treatment recommendations, a standard is set within the regulations. But most states do not have these. So if a pest management company uses moisture meters, what are their instructions on use? When, where and how are they used? In other words, what is the company protocol for the use of these meters?

This becomes a very interesting discussion point if a lawsuit evolves after an inspection. Moisture issues, and mold related to those issues, are also coming up more and more and lawyers are getting pretty savvy about these devices.

In short, if your pest control firm does use these devices then it would behoove you to have some company guidelines for their use. Be sure your company offers frequent training sessions on how moisture meters are used and the associated record keeping, forms, reports, etc., that document their use and findings.

The author is president of George Rambo Consulting Services, Seneca, S.C. Questions can be faxed to him at 864/654-2447 or e-mailed to grambo@giemedia.com.