Question (WOODWEB Member) :
Balanced panels are the norm with flitches etc. this I know, but I'm going to do a flat wall system in paper backed maple (reconstituted ) or regular maple veneer. The panels will be 22" w x 67" tall with grain running vert. and metal strips between the panels. The sub straight will be 3/4" or 1/2" MDF, (1/2" preferred, depending on feedback) with 1 1/2" - 2" x 3/4" plywood framing or studs in a grid of 12" squares honey-combing the back of each panel.
How much can paper backed veneer move to even create a problem in this case? I'm all about over-kill to prevent future problems, but veneering the back of an entire wall seems like a long way to go. Any suggestions for any aspect appreciated.
From Contributor K:
Even panels with paperbacked veneer sheets should be balanced. You can't stop wood from moving but there are a lot of things you can do to help minimize the movement and reduce the chances for warping. Using all the stabilizing options would be ideal but often the specifics of the project won't allow you to use some of them. Picking the best, knowing when to compromise and which could be the most effective is the key.
The environment that these panels are to be installed in should be considered. If dramatic changes in temperature and humidity are expected then more has to be done to stabilize the panels. Exposure to direct sunlight will also influence what measures need to be taken to prevent warping. Acclimation of the veneer is always helpful.
Maple is notorious for moving. Reconstituted maple will move less because it is not actual maple and there is a lot of glue that holds the recon maple face together. The paper backing on the veneer sheet will help to reduce movement. So will a thicker substrate and the finish you use on the face. The honeycomb ribbing on the back will also help to stabilize your panels.
All these things help to reduce the movement in the wood faced panel, they do not prevent it. To further help reduce the risk of warping in your panels, putting a balance sheet on the back is recommended. The best will be to use the same material on the back as on the front, although a lesser grade will suffice, with the same kind of finish. Using a less expensive species veneer sheet would be the next choice. However, this still might not be very cost effective so the next best option is to use a polyback (without a veneer face) balance sheet on the back. Polyback is a polymer resin impregnated paper. It is very inexpensive, about $.40/square foot. In combination with the other steps and considerations it will significantly help to keep the veneer face from pulling and warping the panel.