equilibrium moisture content/ seasoned wood into damp space

[pybyr]

I specifically request permission to ask this in the Boiler Room, even though I know that this might be considered a "general woodburning" question... 'cause in my opinion more than a little of the fact-based horsepower (rather than anecdotal opinions) tends to reside in this particular corner of the forums. Also, those with gasification boilers seem to have a particular appreciation of how much moisture content matters.

I have some wood that seasoned after being cut/ split/ stacked (in a breezy sunny spot) for part of 2011 and up through now and that I won't need until winter- it's looking pretty excellent, and heft and "tone" when smacked all also seem ideal.

It's currently stacked in a place that I'd like to put my newly-cut (2012) wood, cause that spot is under a roofed overhang yet on a sun-baked breezy south-facing exposure.

Space is limited so it's somewhat of an either-or.

One semi-natural place to want to put the "good wood" is in my cellar, where it would be nearest the boiler, out of the weather, and make one and only one move until it goes in the firebox.

But... my house dates from 1840 and has a mostly unmortared stone foundation, in an area with heavy soil and a relatively high water table. Translate: while my basement dries out in winter, it's pretty detectably damp down there now.

I fully recognize that if I were to put unseasoned wood in my cellar during damp months, it wouldn't season at all, as the cellar is probably at near 100% relative humidity- there'd be no gradient for moisture to exit the wood.

What I am trying to think through is: whether humid air, by itself, in the absence of actual wetting of the wood will cause well-seasoned wood to "retake" moisture... and if so, by how much...

I welcome thoughts and suggestions, particularly ones where dots are connected on the basis of how you reach the conclusion you do.

Thanks!

 

[hobbyheater]

I welcome thoughts and suggestions,

Thanks!

Take a moisture meter reading of the wood now and another every week for the duration. You should get a good indication of any change.

 

[BoilerMan]

You could run a dehumidifier, but be forwarned they are expensive to buy and run. Lay plastic on the floor and the walls if you think it'd help keep some of the humidity down, and stack your wood on pallets or something simmilar. If you could open a window or two with fans in them to move the air that may help as well. I believe the wood will take on moisture from the air, how much is dependent on how dry it is now, and the RH of the air as you stated. You could put the wood down there, and only leave a small portion of the dry wood out for your fall burning to get the cellar and wood dried back out. It "wood" free up space for the green wood to season outside. Just my thoughts.................

Taylor

 

[ewdudley]

Maybe take moisture readings from posts and joists and see where they've equilibrated.

 

[maple1]

I think I would try to stack my newly-cut wood in another place - even if that isn't the ideal place that you've currently got your dry wood stacked in. Anywhere out in the open would do, as long as it was off the ground (on pallets?). Then wait until maybe October-November (depending on weather patterns at the time) to put your dry wood in. You should likely have a couple of stacking spots anyway, this rotating of wood will likely happen every year.

Unless you can get lots of ventilation flowing thru your basement - preferrably the natural kind. If it's real damp down there, I might worry more about it starting mold growth on the wood than adding moisture to it (since adding all that volume of wood will interfere with existing airflows) - but testing existing moistures down there as mentioned might help evaluate. Test low, it will be dampest at the floor. I would try to avoid having to add any electrically powered aids (fans & especially dehumidifiers) - they cost over the long haul.

 

[pybyr]

Thanks for the suggestions, all of which make sense.

I own a dehumidifier, and it's even a relatively recent "Energy Star" one and I have found it's a complete wallet buster; the humidity levels in the cellar are high enough that it runs 24/7 even when set to use its sensor to attain only moderate (not even lowest) humidity levels.

As to outside air, a carpenter friend with lots of old house experience pointed out that bringing warm outdoor summer air into contact with cold cellar stone walls ends up being a marvellous generator of condensate, if that's what one's after... in other words, except on the exceptional days of especially low humidity, outdoor air adds to the problem.

What I should try is to take the overflow of my gravity fed spring and run it through an old fan coil I have laying around, and just use a fan to push cellar air around/ through it, to see if it might work as a poor man's ground-source geothermal dehumidifier... lose the electrical demand of a dehumidifier's compressor and only have the fan... still probably won't take the humidity level down to the point of making the cellar suited for wood storage except in the winter.

I should try EWD's suggestion of moisture readings of wood that's down there; much of the house's underbelly is a bit on the soft side due to past decades (before I owned it) when the spring overflow was allowed to pool in the cellar, which let dry rot have a party... Thankfully it is all so robustly framed that it's got margin to still hang together until/ as I get to various parts

Appreciate the suggestions; it's good to have external input and additional perspectives

 

[DaveBP]

Check out a book named "Understanding Wood" by a guy named Hoadley. Something of a textbook for woodworkers. He's got a couple chapters on wood and moisture and related issues.

Yes, wood always is hygroscopic. The moisture content of wood will reach an equilibrium with the ambient air according to its relative humidity and will lose and regain moisture as that changes. Almost verbatim, that.

 

[Eric Johnson]

It will reabsorb some water, but it will also dry out quickly once you put it into a dry area. So, if you can store your wood where it's damp but keep a week's worth (say) someplace to dry before you burn it, you should be OK. There's a huge difference between drying green wood and dry wood that has reabsorbed some water. Huge.

As hobby heater said, a moisture meter will be an invaluable tool for doping out how long you need to dry it before burning.