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I'm in the process of designing a Murphy bed (wall bed) and most plans I've found so far recommend the use of 3/4 inch (19mm) thick plywood. While some like the look of plywood, I was considering some options closer to solid wood.

I live in Germany and edge glued solid wood panels are commonly sold in various sizes (though limited in breadth) and thicknesses.

When comparing equally thick birch plywood and edge glued birch wood panels, what should I take into consideration in terms of their different properties?

I was planning on using edge glued panels (cutting down 2000mm x 600 x 18mm panels) for the visible parts of the bed.

Update: The murphy bed I plan is based the following plan

Edge glued birch: laminated wood

  • IN addition to being a lot more work for something that is hidden, the glued end joints are a very weak connection. Also, while the length of the panel will be stable, the width will not be and that expansion and contraction must be taken into account in the the connections and support for the bed panel. – Ashlar Sep 17 '18 at 17:13
  • @Ashlar - the end joints are usually a comb joint, so they should be pretty strong. Also, I don't think this panel will be hidden. The bed will fold up to stand against the wall, and the base panel will be visible in the room. For example familyhandyman.com/wp-content/uploads/2017/06/…. (But you are quite right about the movement, and I have added that to my answer.) – Martin Bonner supports Monica Sep 18 '18 at 5:25
  • If you squint very hard at this picture you can see the comb joints in the edge of the board. – Martin Bonner supports Monica Sep 18 '18 at 5:31
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The obvious difference is that plywood has grain running in both directions in the plane of the board; edge-glued panels don't.

The result is that if you put a batten under the middle of the edge-glued panel running parallel to the grain, and jumped on it, I would expect the panel to snap. If you did the same to plywood, I would not.

That will matter if you are planning to cantilever the bed out in some way from the long edge - but you probably aren't. Other than that, you should be fine.

Edit: As Ashlar points out in a comment, the other significant difference is that plywood is dimensionally pretty stable, but edge-glued timber will expand and contract across the width. You will need to take this into account in your construction.


I would suggest attaching Lattenrost (slats) to the panel - I wouldn't want to sleep on a mattress lying directly on the panel.

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When comparing equally thick birch plywood and edge glued birch wood panels, what should I take into consideration in terms of their different properties?

The major consideration is wood movement.

A plywood panel is dimensionally stable and will respond minimally to changes in relative humidity, so fixings can be rigid and don't have to take any movement into account. With a solid-wood panel on the other hand movement — expansion and contraction across the grain only — must be borne in mind, especially on wider panels where it can be considerable.

Any decent furniture plans will naturally account for this in the design. Where it's a potential complication is with anything originally intended to be made from plywood but solid wood or a glued-up panel is substituted for the ply.

Other factors relate to strength and stiffness. Outright strength shouldn't be a big issue, few designs push materials beyond reasonable limits and in terms of how they're put together most are over-engineered so there's a good margin of safety. Stiffness on the other hand is something that often needs to be considered, solid wood being generally much stiffer than plywood, and the stronger the wood the more pronounced the difference (a brief look at the values in the Sagulator will give some idea). But where the material is used edge-up (not flat and spanning a gap, as in a shelf) this is far less of a concern.


While some like the look of plywood, I was considering some options closer to solid wood.

Just in case it's the visible plies and glue lines along the edges of plywood that's a major aesthetic issue for you it is common to edge plywood with solid wood where seeing the plies would be undesirable. This is very commonly done with shelves for example.

There's a little on this in this previous Answer.

  • Sorry this is a bit vague but without seeing the design and the specific parts you want to substitute we can only cover the generalities. – Graphus supports Monica Sep 17 '18 at 17:27
  • I added a link to the plan based on which my design will follow – Daniel Sep 17 '18 at 17:42
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    @Daniel, Thanks for the added link. Much of the basic structure poses no difficulty being made from wood and not ply. I hope you can spot a few parts where you do either need to use ply as shown, or adjust the design for this being solid wood rather than ply — the panels with tacked on mitred framing for example, this is really never done with solid wood. Instead a wooden panel is floated inside a frame, to allow the panel to move unrestricted (the standard way frame-and-panel cupboard doors are done). – Graphus supports Monica Sep 18 '18 at 11:37
  • Thanks for the thorough answer. It seems that main part that needs to be from ply is the panel below the mattress. Besides that anything else? – Daniel Sep 18 '18 at 15:40
  • @Daniel, I didn't watch the whole video sorry, just skipped through to look at a few highlights. – Graphus supports Monica Sep 19 '18 at 13:15

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