Are Bugs a problem in storing lumber outdoors/indoors/in a kiln?

[Nick Sorenson]

I'm considering building a solar kiln and do my own drying. After the drying cycle I'd like to store a few hundred board feet cut into usable sizes in my attic.

But I don't want to do this if I'm risking bringing in pests.

Just wondering what the risks and precautions are in doing what I'm considering.

thanks for any advice!

[Scott T Smith]

Nick, as long as your solar kiln reaches the required temps (and duration), your lumber should be sterilized and attic storage would be a great way to maintain the low MC% and sterilization.

Sterilization cycles vary - typically you need for the center of your boards to reach 135F for 4 hours or greater. However, you can sterilize at a lower temp (such as 120F) if you maintain that temp for a multi-day duration.

Depending upon your location, a well-built solar kiln should easily sterilize the lumber.

[Nick Sorenson]

That makes perfect sense and that's what I was thinking. But what about after the drying during storage outside. Can the bugs decide they want to come infest the wood while it's being stored outdoors? Is this something to be concerned about?

[Scott T Smith]

That makes perfect sense and that's what I was thinking. But what about after the drying during storage outside. Can the bugs decide they want to come infest the wood while it's being stored outdoors? Is this something to be concerned about?

Yes, it is absolutely a concern, although in some locations more than others. It is best to go from the kiln into some type of controlled storage.

[Josiah Bartlett]

Watch the weight limit on your attic trusses or rafters!

[ken gibbs]

I recently put a sugar maple top on my kitchen contertop. I cut this maple 14 years ago and have stored it outside or in a garage ever since. These 3/4" planks are ten to twelve inches wide. They were wormy and I wanted the wormy look with tine 1/16" holes. I sized, stained, and added several coats of eurathane to each plank top and bottom outside before I started the install. After a week or so I noticed a small pile of sawdust at one spot beside a tiny worm hole. I cleaned it up and sure enough it was back the next morning. So I put several drops of insecticide down in the hole and after two days the sawdust stopped. So this is what can happen if you air dry your own lumber. This wood is splated with black fungus lines under the stain and its beautiful to spite the dead worm therein.
And commercial cabinet makers know that you can charge extra for the wormey wood.

[Nick Sorenson]

I recently put a sugar maple top on my kitchen contertop. I cut this maple 14 years ago and have stored it outside or in a garage ever since. These 3/4" planks are ten to twelve inches wide. They were wormy and I wanted the wormy look with tine 1/16" holes. I sized, stained, and added several coats of eurathane to each plank top and bottom outside before I started the install. After a week or so I noticed a small pile of sawdust at one spot beside a tiny worm hole. I cleaned it up and sure enough it was back the next morning. So I put several drops of insecticide down in the hole and after two days the sawdust stopped. So this is what can happen if you air dry your own lumber. This wood is splated with black fungus lines under the stain and its beautiful to spite the dead worm therein.
And commercial cabinet makers know that you can charge extra for the wormey wood.

Ha ha :) isn't this awesome. It seems like defects are worth something these days. Distressed furniture, birdseye maple, fungus attacked woods, etc.

[Cody Colston]

By coincidence, I'm also currently building a solar kiln, based loosely on the American Woodworker version which is based loosely on the Virginia Tech version. I'm sizing mine for 300 bf. capacity. I've also been doing a lot of research on both air drying and kiln drying of wood. From what I've read, there should be no problem with a properly constructed solar kiln reaching 135 degrees on sunny days. That will effective sterilize your lumber, eliminating any bug infestation.

Once properly dried, most borers are no longer a problem with the exception being powder post beetles. Termites, of course, are always a possibility but if they infest lumber stored in your attic, you have bigger problems than the wood loss.

But, the bottom line is that you will not be bringing bugs into your attic if the kiln is properly constructed and the wood is properly dried. Leaving the kiln vents closed, especially at the beginning, will help prevent drying too rapidly and will also increase the kiln heat to help in sterilization.

There's a ton of good info at WOODWEB in their knowledge base with articles and answers by Dr. Eugene Wengert, an extension specialist with the University of Wisconsin-Madison. A good source is also "Drying Hardwood Lumber" which is co-authored by Dr. Wengert along with Joseph Denig and William T. Simpson...all noted experts on the subject.

I've read so much on the subject lately that I'm dreaming about drying lumber. :)

[Jon McElwain]

Posted the photo below a couple days ago in the turners forum. It is a piece of silver maple left in the back yard for a year or so. Got worms, but that is okay - I wanted to make a turned piece from it to show off the worm holes. Of course, I had to keep a rag handy to wipe the grub goo off my face shield!

Here is the little guy coming out to say hello shortly before taking an 1800 rpm spin of death.

183733

This is the project after I began hollowing. It is still not done, but it is looking good so far!

183732

[Danny Hamsley]

I cut and air dry hardwood lumber, and powderpost beetles are a serious problem in air dried wood (they drive me crazy!). They do not infest the wood until the wood is dry, i.e., they will not infest green wood. So, wood could be perfectly sterilized in a kiln, then stored in a shed or a barn, and you can still (and with some species probably will) get powderpost beetles. The powderpost beetles really really like red oak, hickory, pecan, and ash. These are ring porous hardwoods where the annual growth ring has an early layer of very large pores, then a second layer with much smaller pores. It is this ring porous design that gives these species their characteristic "grain" pattern. Powderpost beetles seem to really love these ring porous woods.

You can also spray the boards with a borate salt solution that will inhibit the beetles from infesting the wood. I use one pound of borate salt to one gallon of water. There are commercial formulations for just this purpose. A couple of brands are Timbor and Solubor. You can buy these in small quantities.

Like Scott said, if you kiln dry and store in the attic without interim outside storage, you should be good to go. If you plan to store the wood outside, then consider treating the wood with the borate salt treatment before kiln drying.

[Tom Cornish]

Ha ha :) isn't this awesome. It seems like defects are worth something these days. Distressed furniture, birdseye maple, fungus attacked woods, etc.Sadly, this doesn't seem to carry over to screwups, er, I mean manmade defects.