The Forestry Forum

General Forestry => Drying and Processing => Topic started by: Bishop on April 16, 2018, 09:41:10 PM

Title: Drying freshly cut lumber
Post by: Bishop on April 16, 2018, 09:41:10 PM
Hi I'm a newbie ;D

I plan to learn a lot here. I am going to move from NC to TN within a year and I will be living in the country on a nice plot of forest land. :)   (That's the plan)  

So I am planning the type of home that I will be building along with coops so forth and so on. I also watch alot of youtube to learn stuff. This is where my question about drying lumber comes from. I understand the idea of the wood shrinking as it dries out and all that makes sense. But then I watch people building timber frames and saying that one doesn't need to dry the lumber. I have seen a few video's like that. Why don't those Timber frames not twist and distort as the lumber dries, not to mention suddenly having seems?

Thanks and I look forward to the answers :P
Title: Re: Drying freshly cut lumber
Post by: GeneWengert-WoodDoc on April 16, 2018, 10:18:10 PM
Some species have a greater tendency to twist.  Smaller size pieces from the center of the log also twist more than larger.  Faster grown twists more.  Certainly, some people are more demanding about straightness than others.

Welcome
Title: Re: Drying freshly cut lumber
Post by: Don P on April 16, 2018, 10:23:47 PM
Large timbers also check during drying. Part of the natural process that accompanies using large dimension wood. Drying takes a long time for many species. The pines dry relatively quickly, white pine does not distort or shrink too much while drying. If you can mill that a year or so ahead joinery will remain fairly tight. It is not as strong a wood so spans need to be shorter and timber dimensions larger. Something like red oak moves considerably more and shrinks more and will take several years to dry naturally, white oak even longer. Joinery in those species will open more, the timbers will distort more. This is not a structural issue if planned for so much as one of taste, whether a person can accept open joints and distorted timbers. If you can cut oversize and extra and wait, then trim to final dimension just before building the appearance is better. 
Title: Re: Drying freshly cut lumber
Post by: Southside on April 16, 2018, 11:41:48 PM
Welcome to the forum,

My last home was a timber framed home,  I bought it when it was probably 30 years old, white pine and hemlock, mostly 6 x 6 posts and beams.  Many did have twist, checking, etc, but to me that only added to the natural beauty of the home.  Some of the jointery had openings, but nothing that created a structural issue at all, it's just the nature of the product.  I did see a couple videos from some folks who were claiming you can build with green wood without any issues, and yes you can build with it, but there will be things that move or change as time goes on.  

Given your location I would be more concerned with addressing the issue of termites so that you don't have a problem after the frame is built.  One other thing to consider with pine is that pitch (sap) will run each time the wood gets warmer.  So if your trees are felled in say October, and you build over the winter, come spring when things warm up you will have sap that runs as it warms up.  Now once you hit the highest temperature the sap won't run any more, but if you have a heating system, windows that collect sun, etc you will get some pitch run for a while.  Just something to be prepared for so that it does not become a problem.  When lumber is heat treated as part of the drying process this issue is addressed so you don't experience it.    
Title: Re: Drying freshly cut lumber
Post by: Ianab on April 17, 2018, 01:10:21 AM
There are a couple of things that work on your favour and let you use green wood to build.

First is that wood doesn't usually shrink significantly in length as it dries. So your structural parts, posts and beams all stay the same length.  If they started changing in length (by different amounts?) things would get tricky.

The other is how you saw out the beams etc, Unless you have BIG logs, you centre the pith of the log in the centre of your timber, and that helps reduce the distortion as it dries. The tension in the wood tends to be balanced on each side of the timber and, and hopefully it stays straight.

Now there are various other issues you need to consider, but it can be done. 

 * Edited for accuracy, as there are situations where you can get some lengthwise shrinkage, but it's much less than the cross grain amount. 
Title: Re: Drying freshly cut lumber
Post by: moodnacreek on April 21, 2018, 06:18:40 PM
Cedar is by far the most forgiving for this kind of work.
Title: Re: Drying freshly cut lumber
Post by: jayhdjr on April 21, 2018, 08:57:49 PM
Just curious, how does timber frame with a live edge (3 sides milled) work out with green timbers? Would mainly be working with white oak and maybe some red oak later.

Thanks, Jay
Title: Re: Drying freshly cut lumber
Post by: Bishop on April 21, 2018, 10:31:23 PM
Sorry been under the weather since posting.

Wow thanks all. Those are all great responses. I'm really going to learn alot here.