Thread: Storing timber inside workshop vs outside undercover

Wood storage is a problem for any of us who can't resist every windfall or bargain that comes along. When I had more restricted space than I do atm, I tried to be as selective as I could, and not just grab anything because it was free or a bargain, but only acquire stuff with an immediate project in mind. But it never works for me - there are always leftovers from projects that are too good to chuck out or some bargain or gift that is just too irresistible to pass up, so the stash inevitably grows. And grows!

Our house is tucked into a fairly steep slope & goes from a couple of feet above grade to more than 2.5M in places on the "down" side - too much tempting space for storing wood! From your description, I would say the storge conditions you propose are are somewhat similar to mine, neither is ideal, but they are useable. Unfortunately, the deepest side under the house faces the prevailing winds, so although it never actually gets wet, moist air can freely travel through the space at certain times of the year. However, I have successfully 'dried' wood down there over the last 17 years, with no disasters yet. Under the slightly exposed conditions, green wood dries quickly enough at most times of the year to prevent mould & sap stain being a problem (I have suffered a bit of the latter, when drying conditions were particularly slow). But within a reasonable time, everything I've stored from green & stickered properly has equilibtrated to no more than a percent or two over what it would achieve indoors under more 'ideal' conditions. Times vary with thickness, of course, but the rough rule of thumb of 'a year per inch of thickness' has worked pretty well for all but the densest species. As long as you get the MC down to around 13 or 14%, you can safely stack it without stickers, which saves a lot of space, and if you get it out & give it time to get close to the prevailing indoor conditions before using it, you shouldn't have any major problems. Make sure there is no chance that rain could blow in on any tightly-stacked wood, of course, or even cover it with a tarp if you think there is such a possibility.

Even though far from perfect, my storage conditions have not resulted in any disasters so far. My biggest problem is that I've been working on "small stuff" these past few years and the wood stash has begun to gain on me at an alarming rate. I need a series of "big" projects to reduce the pile....

Cheers,

Thanks for the reply. Well with the wild weather we’ve just had north of Sydney turns out it can get pretty wet in the area I was thinking! So might have to stick with inside the shop for important timber and risk it with the dregs.

Timber with air circulating around it will eventually hit equilibrium moisture content in relation to that air - neither getting drier or wetter. Here in Melbourne that might be somewhere around 15%. Pull that timber inside, say in the form of a table top, and in some time (months? years? not days anyway) it'll be more like 10 to 12%. Maybe 8% in a really dry office with 24 hour air conditioning. Whether that change in moisture from outdoor to indoor is a problem or not partly depends on how reactive to moisture change the species of timber is. Personally I'd never worry about something like a Cedar which is very stable, I have seen movement in this circumstance from some of the denser and more reactive Eucalypts though.

How quickly would it react? Eg we had a week of very high humidity recently and lots of rain. I’m guessing given how long it takes wood to dry that short stints of high humidity wouldn’t impact it that much, but not sure.

Also, if the timber got actually wet from rain spray, that sounds like it has more potential to cause issues?

Lostwax, I agree with your general summation. Wood is a hygroscopic material, it will take up or give out water vapour (depending on which way the gradient goes), forever, so what its actual moisture content is at any given moment depends on how long it's been in a given environment & how stable that environment is. Here in S.E Qld, we have a big seasonal swing in relative humidity and we tend to have more open houses than in colder regions so our furniture is exposed to constant fluctuations. I have a small table with breadboard ends and by the end of every wet season, the ends are 3mm too short, & by the following September, they stick out by the same amount. For roughly half the year they are even - it's been like that for about 15 years & I assume it will go on the same way for the rest of its days.

I think it is imperative to pay attention to potential wood movement when designing furniture wherever you live, and whatever wood you use. You never know where things may end up - I've got a few pieces that were made in Canada, brought to Melbourne & finally to Brisbane, so they've experienced a pretty wide set of conditions (the most extreme being in Canada where we had tropical summers but bone-dry interiors in Winter when the heating was going full-bore). One of my early attempts didn't fare well, but fortunately, I was made aware of wood movement before I'd made too many blunders, like glueing panels in their frame. Yep, I really did that!

Which brings me to my second point. You can get away with less than 'best practice' to a limited extent with soft woods like cedar & Hoop pine because they don't develop as much power in expanding/contracting & the soft material is a little more elastic & can absorb the stresses. However, you can't ignore it entirely, I've repaired several old cedar pieces that had major problems due to things like drawer runners glued cross-grain on the side panels. Hard, dense woods are even less forgiving of such practices. I often see a good living example of the power 18mm thick hardwood can develop. My sister has a dining table made by our father & despite my advice to the contrary, he reckoned he'd tame it by glueing (with epoxy) & screwing, thick battens across the under side. The wood in question was yellow stringy, which is a fairly fissile wood at the best of times & the results after a few seasonal cycles are far from pretty, but sister is one of those folks who equate faults with "character" & loves it. To each her/his own, I suppose...

Cheers,
Ian

Originally Posted by lemerv

How quickly would it react? Eg we had a week of very high humidity recently and lots of rain. I’m guessing given how long it takes wood to dry that short stints of high humidity wouldn’t impact it that much, but not sure.

Correct

Also, if the timber got actually wet from rain spray, that sounds like it has more potential to cause issues?

An occasional spray of rain won't make much difference to an already dryish piece of wood.

If the wood starts out green and one end or one side constantly gets wet and the other side it kept dry (or one side gets direct sun exposure and one side doesn't) this is going to produce differential drying and this is what can cause problems.

Originally Posted by lemerv

How quickly would it react? Eg we had a week of very high humidity recently and lots of rain. I’m guessing given how long it takes wood to dry that short stints of high humidity wouldn’t impact it that much, but not sure....

How quickly wood reacts depends on 3 factors, the intensity of the moisture gradient, the density of the wood and the thickness. Yes, short, sharp changes will have minimal effect and the thicker the material, the longer it takes for it to equilibrate.

Originally Posted by lemerv

...Also, if the timber got actually wet from rain spray, that sounds like it has more potential to cause issues?..

It really depends, getting previously dry wood soaking wet will take it back to a very high overall MC, but probably not as high as "green" wood unless it is literally steeped in a bath of water. My observations after a few "accidents" is that dry wood that gets very wet dries out much quicker than it did originally from green, which I presume is because it simply didn't get as "wet" as it was when green. I would certainly give any wood that was subjected to spray or rain extra time to dry "indoors" before using it. You can run a check by weighing a sample board accurately, put it back somewhere in the middle of your 'wet' wood & check its weight every few weeks. When the weight of your sample board stabilises, you can be reasonably sure the rest of the stack has returned to 'normal'.

Your biggest worry with wood getting wet is rot. Fungal spores are everywhere & ready to go the second MC rises above around 20% (& the warmer it is, the quicker they grow). So do your best to get the surfaces dry as quickly as possible...

Cheers,

Originally Posted by IanW

It really depends, getting previously dry wood soaking wet will take it back to a very high overall MC, but probably not as high as "green" wood unless it is literally steeped in a bath of water.

It depends on the wood but takes a lot longer than one thinks for water to penetrate deep into dry solid (no cracks) wood. A really interesting exercise is to systematically soak a piece of dry wood in water over time and then pull it out of the water, let the outside dry off enough so a saw blade won't drag water into a cut, then cut the end off, drill holes into the cut and use a MC meter.

We have several piles of 2" thick uncovered slabs at the tree loppers yard that sit outside all day. Even after days of solid rain the most I have seen the MCs of theinternals of these is about 3% above ambient (nominally 15%)

My observations after a few "accidents" is that dry wood that gets very wet dries out much quicker than it did originally from green, which I presume is because it simply didn't get as "wet" as it was when green.

Correct - the water simply does penetrate that far, and if the water eventually does, dry wood has a changed structure so it doesn't hold as much water.

Your biggest worry with wood getting wet is rot. Fungal spores are everywhere & ready to go the second MC rises above around 20% (& the warmer it is, the quicker they grow). So do your best to get the surfaces dry as quickly as possible...

Agree

In 2009 I milled this Jarrah branch (yes it was a branch off the big log shown in the photos)! in an area that receives ~1000mm of rain every year.
The tree would have been felled in the 1930's but was left behind because the trunk (~2m in diameter) was badly twisted.
Mercifully the termites (of which there are dozens of nearby nests left this log alone.
If you look closely you will see the centre/heart and other sections of the branch are damp.

Bigj.JPG

In fact when I cut the branch off the tree and reached about half a buckets of water poured out of the cut - mainly that damp patch at the bottom of the cut..
But the rest of the wood was effectively dry - not bone dry but waaay drier than the wet patches.
What I suspect happened is that water gone into the heart and other voids through cracks and was stored for long periods of time but it was not able to penetrate far into the wood around it.

slabs.jpg
Another factor that told us this wood was already quite dry was it hardly move when it dried out completely.

I've come to the view-point that you need two types of stacks.

One type for the initial drying of green timbers and another for the storage of seasoned timbers. Obviously, I'd prefer to keep my seasoned timbers indoors but reality doesn't always permit. If stored outdoors, the storage stacks are better protected from the elements than my drying stacks.

Where my drying stacks tend to be temporary things built primarily of loose sheets of corro, in contrast my storage stacks are better constructed. (eg. I actually use screws and fasteners!) For storage I want fairly constant temp & humidity as it is already near MC, so if it gets rained on that's a design fail on my behalf.

Ideally the drying stacks would be as well made, but considering how often I check the timbers for MC and rebuild 'em to keep damper timbers to the top/outside it often just isn't practical.

Now... if the timber is irreplaceable to me, of course I'll be fussier about the stack. But it's the irreplaceable stuff that tends to be stored indoors ASAP anyway!

As to whether timbers should be acclimatised in your workshop before use, that's a different kettle of fish. To my mind, they should be acclimatised to where the new piece will 'live' but, again, in practise that's rarely practical. (Also, for many destinations regarding air-cons and/or natural lighting the conditions are more variable than your shed.)

At least by acclimatising them in your own shed instead you have some metric for quality control.

Originally Posted by Skew ChiDAMN!!

I've come to the view-point that you need two types of stacks.

One type for the initial drying of green timbers and another for the storage of seasoned timbers. Obviously, I'd prefer to keep my seasoned timbers indoors but reality doesn't always permit. If stored outdoors, the storage stacks are better protected from the elements than my drying stacks.

Where my drying stacks tend to be temporary things built primarily of loose sheets of corro, in contrast my storage stacks are better constructed. (eg. I actually use screws and fasteners!) For storage I want fairly constant temp & humidity as it is already near MC, so if it gets rained on that's a design fail on my behalf.

Ideally the drying stacks would be as well made, but considering how often I check the timbers for MC and rebuild 'em to keep damper timbers to the top/outside it often just isn't practical.

Now... if the timber is irreplaceable to me, of course I'll be fussier about the stack. But it's the irreplaceable stuff that tends to be stored indoors ASAP anyway!

As to whether timbers should be acclimatised in your workshop before use, that's a different kettle of fish. To my mind, they should be acclimatised to where the new piece will 'live' but, again, in practise that's rarely practical. (Also, for many destinations regarding air-cons and/or natural lighting the conditions are more variable than your shed.)

At least by acclimatising them in your own shed instead you have some metric for quality control.

I'm in the same frame of mind as Skew,all the good stuff is stored & racked indoors whilst the larger stack at the back of my property covered with colourbond sheeting & weighted down is dry in the main (the ends open to atmosphere) been there for years now.

Originally Posted by John Saxton

......been there for years now.

'Bout time you extracted the digit then, & started using it eh???

Says he, with some lots of wood that have been languishing under the house for more than a decade...

Ian

Originally Posted by IanW

'Bout time you extracted the digit then, & started using it eh???

Says he, with some lots of wood that have been languishing under the house for more than a decade...

Ian

My oldest slabs are also under the house.
They were milled from a WA redgum just outside my shed (not by me) in 1996?
Used some of the slabs as temporary bench tops when I enlarged my shed ion 2011
Stuff shorter than 2.4m scavenged from Builders skips are are also under the house

Then the stuff longer than 2.4m and dozen or so timber slabs leaning up against the sides of the house

And there's a sea container at the tree loppers yard full of stuff milled in 2007-8

And the remnants of 3 wood turners collections and things I've picked up from verge collections in what SWMBO calls "the car port midden"

I've been giving some stuff away but I seem to still be collecting it faster than it goes out.

Originally Posted by BobL

....I've been giving some stuff away but I seem to still be collecting it faster than it goes out.

Yup - sounds awful familiar. I reached the point last year where it dawned on me that I barely have enough time left to use what I've got. But will that stop me from accepting the next windfall that comes my way???

Probaby not....

Originally Posted by IanW

'Bout time you extracted the digit then, & started using it eh???

Says he, with some lots of wood that have been languishing under the house for more than a decade...

Ian

The old adage about saving it for a rainy day rings true in my case ,in fact I have more wood than I'll ever use .I bought some at auctions as well as accessing a lot in the southern forrests of WA,an enjoyable task I might add. Then when my wife retired after me she decided we would spend a lot of our time seeing the world.It's nice to know you have a bank of good wood at your hands.