I am a painting contractor in Michigan interested in buying a good moisture meter. I’ll use it primarily to check whether exteriors are dry enough to prime & paint, but also to check trim before I prime or clear coat it. I am sometimes asked to paint concrete, and for that material also I would like to test moisture content.
There are several different types available — the least expensive runs about $70 and reads an electric current between 2 pins which are inserted into the material being tested. More expensive models apparently have corrections for different species of woods, and some are non-invasive — you run them over the surface.
I haven’t found any good articles rating or assessing them. Can anyone provide information on the best type of moisture meter to buy for my purposes, reliability of units, and any good reading on the subject I should reference. The more expensive models are several hundred dollars, so I’m trying to do some homework first.
Replies
I can't speak to your needs, but I use an inexpensive MM doing home inspections.
For me, an "absolute" reading (i.e., corrected for species and temp) isn't necessary - I use relative readings: suspect a wet spot? I check several areas, and compare readings.
I wonder if that would meet your needs.
And resting the pins against concrete can (apparently) give some indication of relative moisture - a conclusion also based on comparative readings.
View Image
Sojourners: Christians for Justice and Peace
I use a Wagner pinless, upwards of $200 I think. Averages mc down to 3/4". It's been trouble-free for several yrs. Comes with a wood chart as it's calibrated for douglas fir, IIRC. I'm concerned with mc for furniture construction and lumber sales.
Likely you don't need anything that accurate. Presumably even within 10% would do fine. FineWoodworking did a test quite a few yrs ago and concluded that they all worked well, even the $25 one. I find pinless far more convenient, can easily check many areas quickly, but it costs more. In your situation, I'd go for pinless if the cost works for you. Real fast to check a lot of areas.
PAHS Designer/Builder- Bury it!
I have one of the cheap meters (under $100), and a Delmhorst kit with pins and the heavier electrodes that you hammer down into the wood....digital readout....not their top of the line, but up there and a good sturdy professional system that will work for years; paid around $500 Cdn.
I believe you have to spend a certain amount of money to get an accurate reading, and it is money well spent....like I said I have a cheapy and a better one, and I would never buy the cheapy again. That said, I've read a couple of articles in the professional wood products mags that place most of the professional meters of either type within about 1/2% m.c of each other, which is plenty. The professional ones can correct for more species also.
The pinless meters are good (I plan on getting one, just haven't gotten around to it yet), but they meter an average moisture content, and I think you will be interested in the average, but also the moisture gradient, especially for repainting older homes.....is the wood wetter in the core than at the surface?, or vice versa. The pinless ones can't meter that, but you can with pins/electrodes (make sure whatever you buy has a set of insulated pins also if you go that way, so you can get an accurate reading deper into the wood). The ideal is to have one of each, but if you are only going to have one, I would choose the pin type.
The other difference between pinless/pin systems is that the pinless ones can theoretically give an accurate reading in dryer wood......down below 6% or so, so their range is a little better than the pin type, but that probably won't be an issue with you if it's mostly for exteriors, your wood will all be wetter than that.
cabinetmaker/college woodworking instructor. Cape Breton, N.S
Thank you for your comments, which were helpful, and for taking the time to respond to my question!
I have this one. It works just fine, tests wood, plaster, drywall, concrete, and has corrections for wood species.
http://www.professionalequipment.com/xq/ASP/ProductID.89/id.17/subID.261/qx/default.htm
David, I am looking for an accurate meter to do the same things you list, but your link is no longer active. Could you give me an update on what model you have and how you like it?
Thanks--
Mike
As a sawyer and occasional boatbuilder, they are important to me.
Delmhorst has been making them since before WWII, and Ebay has good deals on used ones that the company still stands behind.
Corrections for temp and species, especially in dense hardwoods for meters calibrated for Doug Fir, can be huge...I'd pay attention to them.
I won't use anything but a serious comemrcial-grade pin meter, but your needs may be different....read up on pinned versus pinless before buying:
http://www.delmhorst.com/faq.html
“When we build, let us think that we build forever. Let it not be for present delight nor for present use alone. Let it be such work as our descendants will thank us for; and let us think...that a time is to come when those (heirlooms) will be held sacred because our hands have touched them, and that men will say, as they look upon the labor and wrought substance of them, ‘See! This our father did for us.’ “ --John Ruskin.
Bob, thank you for your comments -- very helpful -- and for taking the time to respond to my question. I love your John Ruskin quote! I'll do so searching for a used meter.
In my primary business of racetrack and retail premium horse hay, moisture meters are very important. We use Delmhorst meters and have very good luck with them. I do know that the wood electrodes work with our meters but have not purchased a set. I can't vouch for the calibration with wood but some models will self-calibrate using a factory supplied piece.
I don't think you can go wrong with the Delmhorst brand.
I've got a Delmhorst pin meter. I think it was under 300 dollars. Their more expensive ones are the same meter mechanism as the cheaper ones, but with more electronic bells and whistles. I just got the basic one, no stored readings or anything like that. It works well.Steve