How to Use a Wood Moisture Meter on Drywall
Drywall is a widely-used construction material essential to our homes and offices. Ensuring your drywall is moisture-free is critical to its longevity, appearance, and structural integrity.
In this article, we explore the benefits of using wood moisture meters for drywall, such as:
- What Is Drywall
- Do Pinless Moisture Meters Work on Drywall
- How to Use a Moisture Meter for Drywall
- What is an Acceptable Moisture Level in Walls
- Why It’s Important to Know If There’s Moisture in Your Drywall
- Not All Moisture Meters Have a Relative Mode
- Are Drywall Moisture Meters Accurate
What Is Drywall?
Drywall is a popular building material for creating walls and ceilings for homes and offices. During the mid-20th century, it started replacing the old lath and plaster technique because it was inexpensive and easy to install. If you live in a home built within the last 60 years or so, you almost certainly live in a home with drywall.
Drywall’s main ingredient is gypsum, a non-toxic mineral that’s mined in countries around the world. Drywall is created by grinding the gypsum crystals to a powder, mixing it with water, and then surrounding it with paper to create the familiar drywall panels. In other words, a drywall panel is just a gypsum core surrounded by paper.
Different Types of Drywall
There are different types of drywall. Greenboard is moisture-resistant and created by surrounding the gypsum drywall core with a moisture-resistant covering. You can also buy fire-resistant drywall and drywall that’s flexible enough to create curved walls or ceilings.
Do Pinless Moisture Meters Work on Drywall?
Yes, the Orion series of pinless moisture meters’ Relative Measurement mode makes it easy to test moisture in drywall. It’s the perfect choice for anyone — building inspector, homeowner, or otherwise — who wants to measure the relative moisture content of drywall.
How to Use a Moisture Meter for Drywall – Tips
Detecting moisture within your walls is crucial to maintaining the integrity and appearance of your drywall. Look for visible signs of moisture, such as discolored areas, musty odors, or crumbling drywall, which may indicate significant water damage.
Follow these simple steps to assess the moisture content using an Orion® moisture meter accurately:
1. Activate the Relative Measurement Mode on your Orion® Moisture Meter
To do this, press and release the SPECIES/MATERIAL button until you see “REL” displayed on the main LCD screen and in the lower-left corner. Next, press the ON/HOLD button to activate the mode. Your moisture meter will now operate on a relative measurement scale (0-100), suitable for measuring non-solid wood or non-wood-based materials, including drywall. To return to Standard Measurement mode, press the SPECIES/MATERIAL button again.
2. Locate a Dry Spot and Record a Baseline Reading
Identify a known dry area on the wall and take a moisture reading. This baseline measurement will serve as a reference point for comparing other readings.
3. Scan the Wall for High-Moisture Areas
Examine the wall to identify spots with higher moisture content than the baseline reading. These areas indicate moisture issues within the drywall that may require further investigation or remediation.
What is an Acceptable Moisture Level in Walls?
Drywall with a moisture content reading of 15 or below is acceptable while using your Orion® moisture meter in Relative Measurement mode. Any reading above 15 could be a concern.
Read more about Wagner’s Orion series of pinless moisture meters.
Free Download – 5 Ways Pinless Moisture Meters Save You Time and Money
Why It’s Important to Know If There’s Moisture in Your Drywall
Drywall and moisture don’t get along. This is because drywall is very porous and easily absorbs and holds moisture. Even a small amount of excess moisture is too much for drywall. If you have excess moisture, you must either dry it or remove and replace it.
If you splash some water on drywall and then wipe it off right away, you should be OK. If it’s a larger amount of water, you can dry it off with a towel and then turn a fan on it until it dries. However, if drywall comes into contact with moisture over a longer period, it can be damaged beyond repair.
Even if you could dry it out, it wouldn’t look the same because it would have lost its shape, and if pressure is applied, it will crumble. The drywall is not load-bearing, so it won’t affect the building’s structural integrity, but it must be replaced.
Mold is also a problem because it doesn’t take much to get it growing in drywall. If you smell mold in your drywall, you should replace the affected panels immediately.
Although greenboard is more moisture-resistant, it’s not impervious to moisture. If moisture passes the covering, you’ll have the same trouble with the greenboard as regular drywall.
Because drywall is so sensitive to even small amounts of moisture, it’s important to get the moisture reading in drywall. You need to know where these minute amounts of moisture are, and if you find any, you need to be able to monitor the drying process to make sure that all excess moisture has been removed from the drywall.
Not All Moisture Meters Have a Relative Mode
While it’s important to use a moisture meter on drywall, not all moisture meters have a relative mode. Using a relative scale may be the easiest way to test. Having a meter read something that is not the correct moisture content for the drywall may be confusing.
However, a relative mode may help the user remember the goal is to find the wettest areas. You must focus on ensuring that the drywall is dried out or replaced in these wetter areas. Also, a digital moisture meter can help a person trace down areas where water may enter the structure.
Are Drywall Moisture Meters Accurate
A moisture meter can accurately detect moisture in drywall. Depending on the type of moisture meter used, it can be accurate down to 0.1% of moisture content in drywall.
How often should I check the moisture content in my drywall?
It is recommended to check the moisture content in your drywall at least once a year or more frequently if you live in an area with high humidity or have experienced water damage.
Can I use a pin-type moisture meter on drywall?
While pin-type moisture meters can be used on drywall, pinless meters are generally recommended for non-invasive and less damaging moisture detection in drywall materials.
What are the signs that my drywall needs to be replaced due to moisture damage?
Some common signs of moisture damage in drywall include discoloration, musty odors, crumbling or warped panels, and visible mold growth. If you notice any of these signs, it is essential to address the issue promptly to prevent further damage.
How can I prevent moisture problems in my drywall?
Regularly check for leaks, proper ventilation, maintaining humidity levels, and using moisture-resistant materials like greenboard in moisture-prone areas can help prevent moisture problems in your drywall.
Consider reading Wood Moisture Meters Buying Guide: Pinless vs Pin-type next.
Tony Morgan is a senior technician for Wagner Meters, where he serves on a team for product testing, development, and also customer service and training for moisture measurement products. Along with 19 years field experience for a number of electronics companies, Tony holds a B.A. in Management and his AAS in Electronics Technology.
Last updated on July 19th, 2023