Is Baltic birch plywood stable enough for interior slab doors?

[mark mcfarlane]

$51 for a 4*8 sheet of real baltic birch is amazing. Is that the pre- or post-Covid-19 price?

Last week I paid $42 for a sheet of 5/8" BC plywood. I was astounded at how expensive it was. I needed a temporary front door for a neighbor's house. Even OSB was something like $30 for a 1/2" sheet.

[Frank Pratt]

There are several grades of BB plywood, so prices vary by grade. But $51 for an 18 mm, 4x8 sheet was almost certainly not Baltic Birch, unless it was damaged stock. I've seen "BB like" plywood in 4x8, but not the real thing.

[Ken Cobbing]

@Mark: Those prices were pre-Covid, but last week I called and checked on pricing and prices do not seem to have changed (although I only checked on 5x5 sheets, so I don't know if the price for 4x8 has changed). I have also purchased BC and CDX plywood in recent weeks and those prices have gone through the roof so I was expecting the same for the Baltic birch and was pleasantly surprised that it has remained stable.

@Frank: the grade of the plywood I have purchased is B/BB, which I believe is the highest grade available. It is "real" Russian birch, with Cyrillic characters stamped on the factory edge. No voids and fantastic quality IMO. I purchase it in both 5x5 and 4x8 sheets and they are stamped from the same Russian mill. The 4x8 sheets actually cost more per sq ft than the 5x5 sheets.

I'm not surprised that your pricing is higher being landlocked in Alberta (beautiful country). My guess is that pricing is much lower in the USA, and substantially lower for those close to Eastern seaports. But I'm certainly no expert.

[mark mcfarlane]

Thanks Ken for the clarifications. Those are really good prices.

[Frank Pratt]

Ken, that does make sense. We pay well over $100 for 4x8 Russian birch, but that is with our funny money. I've never actually used the 4x8, so can't comment on the quality. It's so much more expensive/sq. ft. than the 5x5 Baltic birch & I've not had a project that needed the longer dimension.

[Malcolm Schweizer]

I have used Baltic Birch extensively in furniture building, and I also build high-end mahogany doors. The problems I see with your idea are as follows:
- Weight: it’s going to be really heavy for a hinged door. Pocket doors won’t be as big of a deal.
- You said you wanted to stain them to match other doors. Baltic Birch is not friendly with stains. They don’t penetrate well, and leave you with a splotchy look and it is hard to get a good color. It always looks like stained birch.
- You need a solid wood to mount your hinge to. I would shy away from mounting a hinge into the edge grain of any plywood. A solution would be to rabbet in a solid edge on both sides- so it doesn’t look like you laminated plywood.
- Acoustical qualities may not be favorable. It would be a very hard door and reflect sound. Not a huge deal, but something to consider.

As for movement, I think you would be OK with a laminated door. I would build a flat table and use jointed 2x4’s clamped along the top of the glueup every foot or maybe 18”. Clamp it down on either side to pull the two tight together. I am more concerned with warping than movement, with my interpretation being movement is expansion and contraction, and warping is distortion. Again, I would frame the edges at minimum to counter this. A better idea is build a frame out of a similar hardwood, and groove the inner edges for a single 3/4” panel of birch. That would be one solid door.

Edit: Like this, but rabbet or groove in a ply panel. These were glass doors. We rabbeted in the glass and made a trim piece to hold the glass in.

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[johnny means]

- Weight: it’s going to be really heavy for a hinged door. Pocket doors won’t be as big of a deal.


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I can't say I've ever run into a problem with doors being to heavy and I've made doors with three figure weights. Most clients like the heavier doors.

[Tom M King]

Anytime I was building cabinets for one of my houses, we'd rip it as it came off the truck, or trailer first thing. Saved a lot of handling whole sheets.

I've built a few doors out of two layers of 3/4" cabinet Birch plywood. I parked a wheel of the truck on the middle for clamping. Those doors, in our house in kneewalls upstairs, are still good after 40 years. They're only about 6' tall, but some taller I don't would make a lot of difference.

[Mark Gibney]

Thanks David, I'm going to try to get some locally.
I make benches and TV consoles using PSL beams - I wonder if this is essentially the same stuff?

[Tom M King]

The screw size for house door hinges is no.9. You can get them off Amazon in 2-1/4" length, in your choice of finish. We have had any issue with the hinges on those doors, all the years it took for our children to get to the point that they are grown, and gone, with daily use. I used 4" door hinges for exterior doors, since the doors are 1-1/2" thick.