Wood Movement

[Woodbum]

I have wondered for quite a while about wood movement in our modern heated and cooled homes; where the humidity level remains fairly constant. I lived for a long time in SW Missouri, and have lived in Central Oklahoma for the past 21 years. We normally have gone from heating to AC and back, rarely opening the windows because of all of the wind and dust there and here in OKC.

Is wood movement minimized over the long term in temperature/humidity controlled environments?

I think that it must be. I built a G & G entertainment center ( my apologies to Darryl Peart) with quarter sawn white oak 3 years ago, and the top is 20 x 72, edge joined 5/4 +/- with breadboard ends. I have noticed 0 movement at all in this top since completion. Over the years, I have noticed very little if any movement in other pieces in my house, mostly constructed with flat sawn red oak. Help me out here. What do you guys out there think? I would like to think that it is due to my superior design and construction techniques, but I really think it is because of a fairly constant humidity level. Jump in here Marc, because I am interested in your perspective too. If I am mistaken, please tell me how and why. Let the discussion begin!

[Guest]

I would have to think that wood movement would/should be at a minimum, if any at all, in a controled environment where humidity and temperature rarely if ever flucuate. The only exception I can think of would be in kitchen or bath areas where moisture is put into the air or if a piece sits near a window and is subjected to heating and cooling from sunlight entering the room.

[Howtoworkwood]

Hi Woodbum,

Whilst I am sure you have excellent design and construction skills I am afraid that the lack of movement is entirely due to the lack of moisture cycles that the wood has gone through.

Wood only moves when it gains bound water so if you do not introduce or remove any bound water than the wood will simply stay exactly where it is.

Air is able to carry different amounts of moisture at different times depending on the temperature it is. If you keep the air temperature at a consistant level and rarely open windows (which could introduce damp air) then the amount of moisture in the air will stay roughly the same. This in turn leads to the amount of moisture in the wood staying the same which means it won't move.

You cannot design moisture movement out of a piece of wood, you can only design around it. The only way to stop moisture movement is to control the flow of moisture in and out of the piece which you appear to have done with your environmental control which is extremely impressive.

Please note that the wood will also be at equilibrium moisture content (EMC) which means it is in equilibrium with the surrounding air humidity.

So don't go making a piece of furniture out of green wood and expect it not to split unless you live in a VERY humid house.

I hope that makes sense. Any questions just ask .

Gi