# Air dry vs. kiln dry



## ffquimby (Dec 13, 2017)

Any wisdom on Air dried lumber Vs. Kiln dried lumber? Looking to build a solar kiln, but not sure if I need to.


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## blades (Dec 13, 2017)

a solar kiln is gentle enough that it just speeds up the process of air drying - forced heat kiln tends to cause more warping just due to the dynamics of the process overall. ( in the case of board lumber and of course adds to the production costs of same, but that becomes a trade off vs the 2 years or so of air drying less of course when using a solar kiln) advantage of forced heat though is killing any bugs so most use a combination of the two. Depending on your local Solar can reach temps of the forced air system but can't maintain it for the prescribed bug killing specs for the most part.


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## Bmac (Dec 13, 2017)

Here's a breakdown the way I view it;

Air Drying Lumber;
Advantages-
Minimal cost
If stacked and stickered correctly you should get a predictable product.
Because it dries slowly you get minimal checking.
Working with air dried lumber is easier/more enjoyable. I've read many books by legendary woodworkers who prefer to only work with air dried lumber, I've experienced this also. Air dried lumber just seems to be worked easier, esp with hand tools.
Air dried lumber keeps more of it's beauty (coloring, contrasts, figure).
Disadvantages-
You have to wait for it to dry.
You can't kill any insects/bugs in your wood.
Some pines need high temps to help "set" or 'cure' the resins/pitch in the wood.

Kiln Drying Lumber
Advantages-
You don't have to wait as long.
Kills insects/bugs.
Disadvantages-
Cost
Can get checking if dried too quickly. You can really ruin wood if you don't dry it correctly in a kiln (ie too fast or too high temps)
Lose some color and beauty of the wood.
May lose some workability of the wood.
You still need to air dry to a certain point BEFORE you put it into the kiln.

I've worked almost exclusively with air dried lumber for 25 years, at this point I wouldn't really consider building a kiln. I've got plenty of stock drying and cut more each year. I've also learned a lot, and I've lost some stock, but overall I have had great success with air drying. My patience has yielded many many board feet of quality walnut and cherry to keep me busy at my woodworking hobby. 

I think a lot of guys get really worked up over moisture content. I keep an eye on it, but I simply let green wood sit for a few years stacked, stickered and out of the elements. I then rotate that wood into my shop and let it acclimate there for a few months. After that I just use it. 

I'm sure I missed some "wisdom" here, but there are many on this site that know more than me. Hopefully we'll hear from them so we can even learn more.


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## BigOakAdot (Dec 13, 2017)

Pretty much everything stated in the above post is how I view the two. Love how vibrant the color is with air dried lumber and haven't personally had a problem with bugs or being dry enough to this point. Just be patient. 

I've been considering a solar kiln as well because of how cheap it is and speeds up the drying process.


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## paco_06 (Dec 13, 2017)

ffquimby said:


> Any wisdom on Air dried lumber Vs. Kiln dried lumber? Looking to build a solar kiln, but not sure if I need to.


What will you be using the lumber for? This determines the extent of needed drying.

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## ChoppyChoppy (Dec 13, 2017)

Kiln dried all depends on the setup.

The kiln we have keeps the room at around 80* and uses fans and a large dehumidifer. It takes about a month to dry a load.

Some kilns heat go much hotter and take only a few days. Trade off is more cull.


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## customcutter (Dec 13, 2017)

Tagged for learning experience, milled my first boards today.


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## ffquimby (Dec 15, 2017)

paco_06 said:


> What will you be using the lumber for? This determines the extent of needed drying.
> 
> Sent from my XT1030 using Tapatalk


Will be using the wood for wood projects, i.e. cabinets, furniture etc.


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## ffquimby (Dec 15, 2017)

Bmac said:


> Here's a breakdown the way I view it;
> 
> Air Drying Lumber;
> Advantages-
> ...



Bmac,
Thanks for the insight. I'm pretty much doing everything you had mentioned. I'm also in no hurry to use the lumber, so air drying is not an issue. With the issues of bugs or fungi. Do you know of any methods of dealing with this with air drying lumber? Is there a way to treat the wood without affecting the finished product?

Thanks


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## paco_06 (Dec 16, 2017)

ffquimby said:


> Will be using the wood for wood projects, i.e. cabinets, furniture etc.


OK, so yes, the less moisture content the better. Always best to air dry for a few months before a kiln anyways. From that point, a kiln is only worth doing if you'll use all the lumber right away, or you have a low humidity area to store it. No matter how dry you get lumber, if you store it in a non climate controlled area, it will gain moisture. Ideally, for someone in a non production hobby, best bet is just to do like mentioned above. Air stack until a few months before the lumber is needed, then bring into a shop to let it finish. Keep a dehumidifier in there also to control humidity. Then you're good to go!

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## BigOakAdot (Dec 16, 2017)

To answer your bug question, I remember seeing guys rolling some kind of pesticide on slabs they milled immediately after each cut. This definitely prevents bugs after the wood has been milled, but I'm not sure about th scenario where bugs were already burrowed in the log. 

I would assume once a bug tries to burrow after hag stuffs been applied, it would die from eating the pesticide but I honestly have never looked into it. 

I think the guy who did it was blaisentrees actually. He's a member here who has a YouTube channel and instagram account. Don't hold me to the spelling of his screenname but maybe he will chime in. Worth looking into if bugs concern you.


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## Bmac (Dec 17, 2017)

ffquimby said:


> Bmac,
> Thanks for the insight. I'm pretty much doing everything you had mentioned. I'm also in no hurry to use the lumber, so air drying is not an issue. With the issues of bugs or fungi. Do you know of any methods of dealing with this with air drying lumber? Is there a way to treat the wood without affecting the finished product?
> 
> Thanks



If you are air drying a few simple steps can help minimize bugs/insects and molds.
First, stack to get good airflow through your drying lumber, this helps dry it better anyway and will discourage mold and other destructive growths on your lumber. Also stack off the ground a good ways for good air flow under the stack. Make sure vegetation does grow up under and around your stack. I spray roundup and weedwack around and under my stacks as needed.

Insects and bugs are a little harder to prevent, and you may not be able to completely prevent them. The wood species you mill makes a big difference here. I've had some bug issues with the following species;
Red Oak, maple, pine.
I've had no issues with the following species;
Cherry, walnut, cedar, and sassafras.
I've had very minor bug issues with white oak but it does much better than red oak.

When I talk about bug issues I'm talking about bug issues within the heartwood. All bark and sapwood is vulnerable to insect problems pretty much regardless of the species. I've milled long dead walnut, sassafras, and cedar where the bark and sapwood is full of insect problems but the heartwood is just fine. I've also found this to be the case sometimes with cherry logs, but sometimes these have turned soft and punky. Just need to check cherry as they turn bad faster than the others I mentioned. If I'm milling dead trees like these then I just harvest the heartwood and try to get all the bark and sapwood off before stacking and stickering. If those same logs are red oak, maple or pine and they already have insect problems I don't even bother to mill it. So if you are milling wood with bug and decay issues already you need to stick with wood that has resistant heartwood and not waste time on the vulnerable species.

Now if you are milling live or freshly cut logs with no major insect problem to begin with then you can likely dry it with the bark on, but being proactive and removing the bark and most of the sapwood is not a bad idea for more vulnerable species.

Finally, getting the wood dry makes the wood much less desirable to insects.

Love to hear other people's experience with this issue.


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## coltree (Dec 29, 2017)

BigOakAdot said:


> To answer your bug question, I remember seeing guys rolling some kind of pesticide on slabs they milled immediately after each cut. This definitely prevents bugs after the wood has been milled, but I'm not sure about th scenario where bugs were already burrowed in the log.
> 
> I would assume once a bug tries to burrow after hag stuffs been applied, it would die from eating the pesticide but I honestly have never looked into it.
> 
> I think the guy who did it was blaisentrees actually. He's a member here who has a YouTube channel and instagram account. Don't hold me to the spelling of his screenname but maybe he will chime in. Worth looking into if bugs concern you.



Blaise uses a borax-type solution.


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## Rosss (Jan 11, 2018)

Is that a new to you house or a newly built house?

A newly built house is going to have moisture leaving the concrete basement walls for a year or two after it is built.


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## waross (Mar 17, 2018)

There is huge difference between air dried vs kiln dried lumber. I studied wood technology in college and have a BS in Forestry.
Air dried lumber will never get below the 10-12% moisture content. The cell walls will never be able to seal out moisture and therefore the air dried lumber will change moisture content dependent on the surrounding humidity. The structural strength will never increase.
Kiln dried lumber has a moisture content of about 6%. The cell walls undergo a physical and miner chemical chamge due to the forced heat. This change in the cell wall blocks any future absorption of moisture from surrounding humidity. Also there is a change in the structural properties of the wood giving it better strength. 
This is why all commercial lumber is kiln dried.
That said I currently air dry my lumber. I sticker it up in a large shed that has ventilation and let it dry at least 12 months for every inch of thickness. I have a moisture meter to monitor the wood. Every species dries differently so monitoring is important. 
I am considering building a solar kiln to get the most of out of the lumber. At the moment I have higher priorities. 

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## Bmac (Mar 17, 2018)

waross said:


> There is huge difference between air dried vs kiln dried lumber. I studied wood technology in college and have a BS in Forestry.
> Air dried lumber will never get below the 10-12% moisture content. The cell walls will never be able to seal out moisture and therefore the air dried lumber will change moisture content dependent on the surrounding humidity. The structural strength will never increase.
> Kiln dried lumber has a moisture content of about 6%. The cell walls undergo a physical and miner chemical chamge due to the forced heat. This change in the cell wall blocks any future absorption of moisture from surrounding humidity. Also there is a change in the structural properties of the wood giving it better strength.
> This is why all commercial lumber is kiln dried.
> ...




I really hate to disagree with you, but everything I've read and studied refutes what you are saying. Now granted I do not have a degree in forestry but this is my understanding;

Wood, whether air dried or kiln dried takes up moisture and eventually equalizes with the environment it is in. I believe this is called the wood's EMC, Equilibrium Moisture Content. I know for air dried in the Mid-Atlantic area of the country my EMC for outside storage is around 12%. That means lumber stored outside will never go below this EMC. But once that wood is moved inside to my shop and I let it acclimate for a few months. It then reaches the EMC for my shop which is about 8-9% (I do not have a completely climate controlled shop). Then I build and bring the product inside where it continues to dry some and eventually reaches the approximate EMC of 6% for a controlled climate like my house.

Kiln dried lumber is dried to 5-6%, but that wood will gain moisture if not stored in an environment that is 6% EMC. So if I bought kiln dried lumber from a lumber yard that was storing it outside, the wood will be wetter than it was once it left the kiln. In fact, if you stored kiln dried lumber outside long enough it would reach the same EMC of air dried lumber stored outside.

From my study there is no process that you can do to wood, whether its kiln drying, a finish or a sealer, that prevents wood from gaining and losing moisture from it's environment.

Now I do agree that kiln dried wood behaves differently, the rapid drying can create built up internal stresses in kiln dried wood. Also I believe that air dried is easier to work with hand tools, easier to bend, and retains more vibrant colors.

This give and take of moisture is why one needs to build with that concept in mind, frame and panel construction is a prime example. You need to build with the idea that the wood is free to move across the grain.

You can also build using moisture content to your advantage. Here is a photo of a chair made from air dried wood, I would have never been able to bend those arms with kiln dried lumber. The process I used for those arms is bent lamination and I used wood that was a little wetter that my 8-9% acclimated wood in my shop. Once bent I let it acclimate and then I shaped it.




Also, I used wood for the seat that was 11-12%, outside EMC, and used drier wood for the spindles and legs. Now as the wood in the seat dries and shrinks it creates a tighter joint for the legs and the spindles. This concept has been long known by chair makers for centuries and knowing how wood behaves in it's environment, regardless of it being air dried or kiln dried, can mean success or failure with your projects.


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## waross (Mar 17, 2018)

Bmac said:


> I really hate to disagree with you, but everything I've read and studied refutes what you are saying. Now granted I do not have a degree in forestry but this is my understanding;
> 
> Wood, whether air dried or kiln dried takes up moisture and eventually equalizes with the environment it is in. I believe this is called the wood's EMC, Equilibrium Moisture Content. I know for air dried in the Mid-Atlantic area of the country my EMC for outside storage is around 12%. That means lumber stored outside will never go below this EMC. But once that wood is moved inside to my shop and I let it acclimate for a few months. It then reaches the EMC for my shop which is about 8-9% (I do not have a completely climate controlled shop). Then I build and bring the product inside where it continues to dry some and eventually reaches the approximate EMC of 6% for a controlled climate like my house.
> 
> ...


There is a cellular change that occurs when kiln drying lumber there by limiting the uptake of moisture. When you spend 4 years getting a degree in wood technology then come back and we can talk. The books you pick up in barnes and nobles are for woodworkers like yourself and do not study the molecular structure of the wood. Go ahead and refute, I have all the books to show otherwise as well as studies and many papers. Typically this is why I never post in these forums because arm chair quarterbacks always know best. 


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## waross (Mar 17, 2018)

I apologize if I sound rude, but if the question is asked and a sound scientific answer which is universally accepted throughout academia and industry is given then just accept the answer instead of relying on hogwash from a bookstore. 

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## Bmac (Mar 17, 2018)

waross said:


> There is a cellular change that occurs when kiln drying lumber there by limiting the uptake of moisture. When you spend 4 years getting a degree in wood technology then come back and we can talk. The books you pick up in barnes and nobles are for woodworkers like yourself and do not study the molecular structure of the wood. Go ahead and refute, I have all the books to show otherwise as well as studies and many papers. Typically this is why I never post in these forums because arm chair quarterbacks always know best.
> 
> 
> Sent from my SAMSUNG-SM-G891A using Tapatalk



Well you've already changed your statement. In your first statement you said;
"Kiln dried lumber has a moisture content of about 6%. The cell walls undergo a physical and miner chemical chamge due to the forced heat. This change in the cell wall blocks any future absorption of moisture from surrounding humidity."
In the statement above you say;
"There is a cellular change that occurs when kiln drying lumber there by limiting the uptake of moisture"

So, does kiln drying block or just limit moisture uptake, there is a BIG difference between those two statements. If it just limits moisture uptake than my response to you about EMC was correct, it's just kiln dried takes longer to pick up moisture, but it still picks it up.

So from your first statement I'd love to see the evidence of the following-
-That air dried lumber can never get below 10-12%.
-That that Kiln dried lumber will not increase in moisture content, or MC.

Here is a very sound reference I've found, I'm sure you've heard of Dr Gene Wengert in your 4 years of study;
http://www.thisiscarpentry.com/2010/09/03/moisture-content-wood-movement/

More sources;
https://www.extension.purdue.edu/extmedia/FNR/FNR_403_W.pdf
http://www.woodweb.com/knowledge_base_images/zp/equilibrium_moisture_content.pdf
https://research.cnr.ncsu.edu/blogs...isture-Content-of-Exterior-Wood-in-the-US.pdf

This arm chair quarterback is open to learning.


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## waross (Mar 17, 2018)

Bmac said:


> Well you've already changed your statement. In your first statement you said;
> "Kiln dried lumber has a moisture content of about 6%. The cell walls undergo a physical and miner chemical chamge due to the forced heat. This change in the cell wall blocks any future absorption of moisture from surrounding humidity."
> In the statement above you say;
> "There is a cellular change that occurs when kiln drying lumber there by limiting the uptake of moisture"
> ...


Obviously I am not going to change your "opinion". I attempted to educate the difference which is significant and on a cellular level. If you wish not to believe proven science then that is your right. I will not debate you further. You stated in your first post that you believed others may have more information; however your ego fails to let you hear and understand. Keep doing what you do but please do not spread bad information on a topic you obviously to not totally understand. You have proven once again that the forums are full of misinformation. 

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## Bmac (Mar 18, 2018)

waross said:


> Obviously I am not going to change your "opinion". I attempted to educate the difference which is significant and on a cellular level. If you wish not to believe proven science then that is your right. I will not debate you further. You stated in your first post that you believed others may have more information; however your ego fails to let you hear and understand. Keep doing what you do but please do not spread bad information on a topic you obviously to not totally understand. You have proven once again that the forums are full of misinformation.
> 
> Sent from my SAMSUNG-SM-G891A using Tapatalk



Funny thing is you actually could CHANGE my opinion if you showed me the scientific data you say you have.

I did say in my first post that I believed others may have more information and I would love to learn. This exchange has stimulated me to do further research.

So let me say that I did find that your original statement does have some truth to it, under certain circumstances. I'd like to dispel any misinformation.

If you look at kiln drying lumber, you find it is a relatively new process to the centuries of woodworking. It's big commercial advantages are that it reduces weight for shipping, sets pitch in pine, and effectively kills any insects in the lumber. It can effect lumber quality if not done correctly.
There are many ways to kiln dry; solar, steam heat, low temp, high temp, compression, vacuum, dehumidifying, and probably more that I missed.

What I found was that kiln drying at high temps will actually change the cellular makeup and reduce the hydroscopic ability of the wood to take up moisture.
So you are absolutely correct in that instance and I've learned something!

It appears though that the other methods of kiln drying do not affect the hydroscopic nature of the wood like high heat kiln drying does. The key seems to be if you want to reduce the hydroscopic nature of wood than you need to dry at high temps. So in affect we are both correct, depending on the method of kiln drying.

Here are some sources that look into high heat methods of kiln drying;
https://www.fpl.fs.fed.us/documnts/pdf1960/mathe60a.pdf - look in the conclusion, high heat reduces the hydroscopicity differently than other kiln drying methods
https://www.scionresearch.com/__data/assets/pdf_file/0009/58932/NZJFS611976KININMONTH101-107.pdf - In the abstract, there is a progressive reduction of swelling and moisture uptake as drying temperature is increased
http://citeseerx.ist.psu.edu/viewdo...6C9C386?doi=10.1.1.666.8647&rep=rep1&type=pdf -- another showing the relationship of drying temp to hydroscopicity
https://link.springer.com/article/10.1007/s40725-016-0034-z -- overview of kiln drying -- some evidence that high temp drying will close off some cell walls

So lets hope this interaction, in a small way, helps spread correct information on these forums. I've shown research articles, both scientific and summary statements to prove my side of the argument and to prove your side of the argument.
Waross, perhaps you would like to add to this? Would love to see your scientific data also. I understand my info was just gained in a superficial web search and you may have information I was not able to access.


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## rarefish383 (Mar 20, 2018)

When I went to the University of MD under a Botany major, many of our courses were based on the studies of Dr. P.P. Perone. There was a new fellow on the block by the name of Dr Alex Shigo. Some of his studies were being taught, or at least looked at, like CODIT. If the studies of Perone were later proved by Shigo to be incomplete, or flat out wrong, does that make my degree invalid. I put in my time at Md, and then 40 more years in the tree care industry. If we treated trees using Perones teachings, and they were proven wrong, why, now, almost 50 years later, are they still standing. One must be careful when presenting scientific fact to the general public, because those facts are often limited to the environment they were tested in, and if they are 99.9 percent accurate, someone will find that .1 percent exception. As soon as I saw the word "Limits" used, I thought, Oh,Oh, here we go, someone is going to find the exception, and they did. I quit thinking, and trying to prove, I was smart when I realized that every bit of knowledge in the universe is already there, we just haven't found it yet, Joe.


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## Sawyer Rob (Mar 21, 2018)

My wife tell me that I have a BS in a lot of subjects and I didn't even have to go to school to get it... lol lol

MY Cabinet making career (I owned/ran my own custom furniture/cabinet shop) tells me, that when I bought kiln dried lumber and built furniture out of it, that AFTER it was built, "IF" the RH went up, the furniture "moved"... Just like the same species did when I "air dried" the lumber that I also used from time to time.

In MY experience, kiln drying lumber does NOT STOP wood movement when the RH changes, I don't care what a book says, it happens, I've seen and dealt with it myself as a professional furniture/cabinet maker...

SR


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## BigOakAdot (Mar 21, 2018)

This doesn't really apply too much to this comparison but relates to humidity I assume. 

I made a checkerboard style walnut/cherry cutting board. Got a pure tung oil finish on one side and set it aside for quite come time. (Tends to happen to a lot of my projects lol) 

I then pulled it back out and had it laying in my room where my wife decided to stick it on the window sill ‍ Right when I saw that I knew it had gotten at least 4 hours of direct sunlight. The thing mine as well been a curved bar seat when I picked it up. 

Was very upset about it and don't you know the next humid day (summer in philly area is super humid) the thing went right back to where it was. 

It was air dried so I'm sure it wasn't super low moisture content and played a large roll. Just thought it was an interesting story when it comes to wood
Movement. It's now at my uncles and seems to be holding up just great in his kitchen.


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## bowtechmadman (Mar 21, 2018)

Wow some interesting reading.
A little off topic but I think it applies to the little jousting contest presented by Mr. Academia. Dr. Larry Nassar was once thought of as being the most renowned Osteopathic Dr's in the nation. Now he's in prison for where he belongs for molesting countless athletes. Just because someone say's it's true and right it might not always be the case.


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## Bmac (Mar 21, 2018)

Sawyer Rob said:


> My wife tell me that I have a BS in a lot of subjects and I didn't even have to go to school to get it... lol lol
> 
> MY Cabinet making career (I owned/ran my own custom furniture/cabinet shop) tells me, that when I bought kiln dried lumber and built furniture out of it, that AFTER it was built, "IF" the RH went up, the furniture "moved"... Just like the same species did when I "air dried" the lumber that I also used from time to time.
> 
> ...




Words of wisdom from someone who has firsthand experience; ignore wood movement and you'll have unhappy customers or go out of business.


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## AZWoodworker (Jan 29, 2022)

waross said:


> Obviously I am not going to change your "opinion". I attempted to educate the difference which is significant and on a cellular level. If you wish not to believe proven science then that is your right. I will not debate you further. You stated in your first post that you believed others may have more information; however your ego fails to let you hear and understand. Keep doing what you do but please do not spread bad information on a topic you obviously to not totally understand. You have proven once again that the forums are full of misinformation.
> 
> Sent from my SAMSUNG-SM-G891A using Tapatalk


I could understand not arguing with some guy in a bar, but on a forum, it is a place to educate and I for one would like to be able to look at the studies or data and have a definitive statement. I am looking to move My furniture online to sell in more high moisture content states. I have thousands of board feet of rough lumber that have been air-dried in Arizona. I don't have a high-end moister meter to go deep into the wood but when opened I get about 10 percent. If I am building and shipping to high humidity, I can build for expansion, but I still would like some definitive answer for vulnerable procedures on stocks. In looking at data all wood acclimates to the moisture content of the area. I have no other data that refutes this because science or those that have degrees seem to give the answer of "believe proven science". Science is a method. The observation, identification, description, experimental investigation, and theoretical explanation of phenomena. or another more structured definition; A systematic method or body of knowledge in a given area. Armchair quarterbacks trying to understand things. You will be surprised how much this statement is given if you don't believe it... Sounds like it is a trained statement in universities. I went for engineering but never took that class. 

I am not trying to be critical, but some studies and experiments would be great. An expert should be able to educate instead of taking his blocks and going home.


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## Sawdust Man (Jan 29, 2022)

Watch out for "education" and "degrees"!!!
There is no classroom substitute for real world experience, and "scientific facts" are only facts if they are in fact true.
If wood moves by being exposed to increased humidity after being kiln dried, then it does, doesn't matter what some guy with letters after his name says.
The cellar structure probably is changed during kiln drying, but change doesn't necessarily mean a real improvement.
I think most true experts are the folks who make a living at a thing, not those who get paid to talk about it.
Personally I'd much rather be taught by doers than talkers.

In my 35 years of sawmill and cabinet shop experience, I have had very poor success with air drying lumber, and therefore I prefer kiln dried wood.
Over the years, we have lost thousands of bf to bugs and mold / stain, trying to air dry lumber in the PNW, in other climates it may be more doable, climate makes a big difference with wood handling.
After 43 years working with lumber in the pnw, I'm now in Missouri, so I have to re learn how it's done here.

My advice is to find folks in your climate who's living depends on the methods they use, and learn from them, they are the true authorities on the subject.


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## blades (Jan 30, 2022)

Generally kiln process is to take it down to 6-8% then stack for awhile and let it stablize, around 12%. Now if shipping wooden products interstate or anywhere else in the world it must be kiln dried or at the minimum heat treated to kill bugs. heat treatment does little to dry the wood. Your air dried product will still have to be heat treated by some co. that is certified in that.


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## AZWoodworker (Feb 7, 2022)

blades said:


> Generally kiln process is to take it down to 6-8% then stack for awhile and let it stablize, around 12%. Now if shipping wooden products interstate or anywhere else in the world it must be kiln dried or at the minimum heat treated to kill bugs. heat treatment does little to dry the wood. Your air dried product will still have to be heat treated by some co. that is certified in that.


Thank you. Any more information on that? Is there an interstate law on that that you are aware of? I have not seen bugs beyond the bark which I remove if I see any, and have milled some Ash that had worms, but separated this from other wood and killed them. Are there other bugs I would be missing in the wood? I made enough with what I have dried into pieces for furniture and other wood items and kept a close eye on anything that might be bugs as I cut. So I have experience with my procedure. This does not mean I would be able to discover eggs that would hatch in a more moist enviroment. 

I live in Arizona. I have built many things with air-dried, but only locale and minimum, but lots of personal or friend projects. When I air dry it is off the ground, has metal roofing on top, stickers are 1.5 inches at 18 ins to 2 ft, and the temp gets to 115 or higher in the sun, ( A lot higher sometimes I feel like I landed on Mars) and I check the wood often for any bugs. I do try to remove bark as I can based on what I am milling and how easy it is to do at the time, and I mostly mill into 2 1/2 in slabs but even after a bit I go back and knock off bark where I can. I've checked with UV routinely and found scorpions so I now have Geckos throughout the backyard that eat them. I love milling logs, and moving around heavy 10 or 16 footers and do it mostly with chainsaws. I also have local bandsawyers that I do loads now and then. Where any bugs come in on the logs or are seen in bark I chemical kill. I mill Mesquite, Chinese elm, Rosewood, Russian Olive, Afghan Pine, Mulberry, and ash mostly from urban areas. 

I need to check any laws on exporting out of state and maybe need to include a disclaimer that the wood is air-dried, and deal with it in Marketing ensuring customers know. However, if there are laws that prevent transfer even the possibility of bugs, then need to build a kiln. If it needs to be certified then have to find and use a certified kiln or get certified myself, which sounds horrid. 

My normal job is being hammered in the fear of Covid and I need to put this production into place or ...


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## blades (Feb 8, 2022)

Yes there various state and federal laws on wood product transportation across state / county lines as well as for international shipping. These all require at the minimum heat treatment protocols. The Ash borer is a classic example of why these protocols are now in place. By the way this extends to firewood as well. A simple disclaimer will not protect you from the wrath of Federal or State regulation agencies.


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## blades (Feb 9, 2022)

Not real difficult to build a kiln but pricy. there are a set of time lengths to maintain various temps in the kiln. certification requires it to be inspected and certified by agency to those parameters.


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