Oversized Pocket Door with Glass Panels

A woodworker worries about weight concerns, hardware choices, and other practical issues with an 8' by 10' pocket door. June 22, 2010

Question
An architect is asking me to make a 10' by 8' wide pocket door with three stiles (one down the center) and two 1/4 inch glass panels. My first concern is the hardware will detach at some point from all the weight so I plan to make custom header rail to attach the sliding door hardware on with three threaded rods four feet down each stile to get a solid hold on it.

My second concern is what material I should use so it doesn’t warp at such a large size. My thought is some sort of plywood core that the threaded rod can hold on to with glued on MDF panels that possibly can hold it plumb. I have freedom to make the stiles considerably wide and I can make the door thick as I'm building the wall where the pocket door will enter. I also can convince the architect to change his hardware spec if needed.

The design he wants looks like this:
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The empty spaces are glass. What do you think? Does anyone have any suggestions?

Forum Responses
(Architectural Woodworking Forum)
From the original questioner:
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Corrected sketch - the apostrophe's are the 1/4 glass.



From contributor W:
The hard part will be the right stile where it seems to jog in under the top glass, and then jog out and back in again at the bottom. I guess the top right corner is chamfered. I would suggest making this door about three inches thick, since the architect seems to be trying to achieve a massive and clunky look. Put wheels underneath it.


From contributor J:
To be honest I think you’re over thinking it. Unless you’re going to make the door with steel, it's not going to be outrageously heavy - maybe a few hundred pounds? I've used Grant tracks in the past and they make kits up to 1000 lbs. For your application, depending on the exact materials used, I'd guess you'll probably be able to use the 275lb kit.

As for materials that should have been spec'd by the architect, no? I build a lot of solid 8/4 panel doors and haven't had any problems with the doors warping. Your’s has that wide section though, that could get a bit tricky. You could also use a laminated core and glue on your own skins. Of course with a door that size the biggest thing to remember is to make sure you can actually get it in the building.



From the original questioner:
You are right. I didn’t consider how to get it in the building. He spec’d wood and a painted finish, so was worried about warping at such a large size more than anything. Wheels are probably the way to go so they never call me back. I know my drawing formatted bad. What's important is there is no way to get these doors into the building. I will have to tell the architect to redesign smaller ones and as such my worries are gone.


From contributor F:
I don't think this is as daunting as you first related. I agree that aside from the egress issue of the doors size the weight is not a big problem. 2 1/4 thickness is plenty. Vertical grained Doug fir will stay straight and hanging from the top is always a good minimal stress situation. The barn door hardware shown in the photo is a bit hard to use in a pocket if that was a thought. Hafele has several choices.


From the original questioner:
I was really unsure and concerned with warping. It did occur to me that the hanging situation would reduce the stress but I thought additional drying was unavoidable and warping at such a length would show. I thought I'd be better off making some sort of composite in the shop with MDF and plywood. It occurred to me that this would be heavier and possibly not hold at the top where the hardware was fastened.

My spec is the Hafele hardware. Though I'd rather use the Grant ones since I've worked with them before and they don’t require all the assembly time the Hafele ones seem to always require. I'm going to try the doug fir in 2 1/4 if he presses for this size and makes me fabricate it in two pieces to get through the door.



From Gary Katz, forum technical advisor:
Good thinking about getting the door into the building. Elevators aren't that big. I've been there before and it can get embarrassing. By making two doors you'll also solve the hardware problem - if you want to use Grant. Grant does not make a heavy duty truck that mounts to the top and side of the door, only top mounted, and that's for doors up to 275lbs. The problem with top-mounted hardware on heavy doors is mounting the screws or bolts in the top rail of the door and not in the end grain of the stiles. Even if you mount the hardware in the top rail only, the screws have a lot of weight on them. I've had them pull out on 6/0 x 12/0 2 1/2 inch French sliders with dual pane glass.