Delmhorst Meters Leading the Way for Accuracy in Restoration

By Paul Laurenzi Vice President of Sales & Marketing for Delmhorst Instrument Co.

Proper use of moisture meters in a water damage or mold remediation claim is the fundamental key to success as a restorer. This article provides basic knowledge on the differences between the types of meters on the market, how they work, and what information they provide.

Which Meter Should Be Used?
The two types of moisture meters on the market are Pin type meters and Pin-less meters.

Pin Type meters operate on the principle of electrical resistance (conductivity). They require the operator to penetrate the material being tested. The electrical resistance of the material between the points of contact, which is influenced by the presence of moisture, is measured and displayed by the meter.

Pin-less meters, on the other hand, use capacitance technology to detect moisture. The sensor pad, which makes surface contact with the material being tested, sends a radio frequency signal into the material.

A pin-less moisture meter is an excellent tool because you can use it to quickly scan the surface and determine if moisture is present.

Pin type meters are capable of detecting precisely the source of moisture by penetrating through the surface at different depths. While some people are concerned about making holes in the material, this limited damage is a non-issue considering the excess damage that could occur if this moisture were left undetected.

Pin type meters also have various accessories that can be attached to provide further information about moisture conditions in hidden areas.

What does that number mean?
Both pin type and pin-less meters are equipped with different scales that give the operator the flexibility to measure different materials.

Most of the meters on
the market feature a
wood scale and a
reference scale. Delmhorst Instrument Co. is the only manufacturer to offer meters with a calibrated drywall scale. Below is an interpretation of the different scales and readings.

Wood:
Most moisture meters have a scale that is calibrated on wood, covering a range between 6% and 40% moisture content, depending on make and model.

All Delmhorst models come with a wood species correction chart or include built-in species corrections. With the built-in corrections, the operator can change the meter setting to a particular species to obtain a corrected reading. However, in most cases, the reading can be taken at face value on construction grade lumber.

Concrete and other building materials:
When testing any building material such as plaster, concrete, brick, insulation, etc., readings in the low end of the scale indicate a “drier” condition; readings in the upper end of the scale indicate a higher moisture level in the material.

Drywall
Delmhorst Instrument Co. offers several models that include a specific scale to check the moisture content of drywall. This scale is in addition to the wood and reference scales mentioned above.

This feature is valuable because it is calibrated for drywall, and provides a reading in percent moisture content, offering more specific information about moisture conditions and the likelihood of mold development in drywall. Since drywall is an excellent source for mold to flourish, having a quantitative measurement of the percent of moisture content allows you to make more informed decisions regarding remediation.

Moisture meters – key tools in monitoring the drying process
For many years, large restoration companies have used moisture meters as an integral part of the drying process. In a water damage or disaster situation, it is important to dry out the structure properly and completely. Years of drying experience and the latest equipment will be null and void if meters are not used to verify that the structure is dry. Mold and mildew can form; structural damage will occur, and a simple water damage can easily turn into an inconvenient, costly disaster.

It is necessary to make moisture measurements every day during the drying cycle to determine if the equipment is doing its job. Adjustments can be made along the way based on data obtained from meter readings.

Verification that the structure is dry is done by making final moisture checks before pulling any equipment. This last and important step allows you to sign off with confidence that the job was done right.

What about Temperature and RH?
Another factor to consider during the drying process is Temperature and Relative Humidity. While the actual moisture level of building materials is important, understanding and adjusting for the environmental conditions of the building envelope plays as important a role in the effectiveness of drying equipment. This in mind, measure the temperature and relative humidity in conjunction with moisture so that ultimately, you can achieve a lower GPP (grains per pound). This will allow for dryer air, enabling the air movers and dehumidifiers to perform at optimal efficiency.

Delmhorst Instrument Co. offers several thermo-hygrometers, each of which provide dew point temperature and GPP, eliminating the need for a psychometric chart.

What’s next in Moisture Meters?
Manufacturers of moisture meters and thermo-hygrometers are constantly looking for ways to improve products that provide information which the specialist needs to make good drying decisions. This information is ultimately brought to the customer, instilling confidence that their home or work place is a healthy, safe environment.

Models like the Navigator Pro from Delmhorst are the most advanced offerings for the restorer. The new Navigator Series integrates both the pin mode and pinless mode with a thermohygrometer option. It provides ease of use for checking moisture in drywall, insulation, wood, concrete and plaster. The Navigator Series makes it easy to trace leaks, find exterior moisture and locate dry rot.

In “Enhanced” mode, the user can define up to five jobs with up to 32 rooms and store the readings by location within each room (floor, ceiling, wall). “Pin” Mode features three scales: wood, reference and sheetrock. “Scan” Mode features pinless pad measurement using the reference scale (0-300). The thermo-hygrometer (Pro meter only) measures temp/RH and calculates GPP/dew point. Full screen reading recall with date/time stamp, intuitive menus and infrared PC linkage round out this meter’s features.

Paul Laurenzi is the Vice President of Sales & Marketing for Delmhorst Instrument Co. For nearly 60 years, Delmhorst Instrument Co. has been the leading manufacture of high-quality moisture meters. Initially, Delmhorst sold one model to building superintendents in New York City to help them identify leaks in roofs and plaster walls. Today, the company serves more industries than all of its competitors combined, and is recognized as the market leader in each of those industries.