We need to have doors made to match existing vertical wood paneling, which is 5" wide tongue and groove rift oak. 8 feet tall, 30 inches wide, 1 3/4 thick.

The look is to have plank doors on both sides with perfectly aligned v-grooves - so six vertical planks, no edges, nothing. Similar to this.
https://www.trustile.com/sites/default/files/styles/content_slider/public/slider-v
g1000-01.jpg?itok=iChtl-Z0

But need to match existing paneling, so doors like pictured would not work.

I have read the Wood web database on plank doors, and saw suggestions on ladder style constructions. The problem is that the mill offers 5/8 inch thick planks and they can mill them square edge (with V added) or tongue and groove, but not willing to go to 1/2 inch thick. They are happier to offer 3/4 inch thick,

For 1 3/4 inch thick door even 5/8 thick panels on two sides leave only 1/2 inch for the center. These are all interior doors with humidity controlled space (well, there is a humidifier and dehumidifier).

For a ladder-style, would 1/2 thick really work?
Another suggestion was to glue to plywood but with 1/2 thick plywood even rift sawn oak seems iffy?

I am in a fairly remote area, so limited to what is locally available. What should I ask for? The wood people I talked to scratch their heads but are not experienced. But willing to try.

I would greatly appreciate your advice.

Absolutely, never glue 1/2" solid wood to plywood.

The argument they make is that solid hardwood floor is routinely glued to plywood (but that is 3/4 inch thick hardwood) which on a face of it makes sense but still.

I've never known anyone that glues solid hardwood floors down. Why do they insist on a gap around the room if the hardwood isn't going to expand. Gluing hardwood to plywood is never a good idea, no matter what the argument is. It contradicts the most basic law of woodworking.

Can you cheat on the thickness and make these 2-1/4" thick? If so then you could make up the two sides independently by mounting the 5/8" thick boards to 1/2" plywood. No glue. Screws through the plywood into the backs of the boards.

Then you could vacuum or weight press the two plywood faces together and end up with a 2-1/4" thick door slab that should remain stable.

BH Davis

There are some door gurus on here that can give you a good answer. One even wrote the book on the subject. But I wonder, why not use a shop made veneer and vacuum bag this? If the v grooves need to be very deep, you could inlay a narrow solid wood strip before laminating. Just a thought.

I made this door to do the same thing you need. 2 1/4” thick, 5/8” thick skins over a soft maple ladder frame. Groove to groove with a spline. I only glued half of the paneling width to the ladder frame so it could move a bit.

View higher quality, full size image (4032 X 3024)

Where is Dave?

I'd do a veneer thick enough to get my V into and plow those out on the cnc.

I'd also probably turn down that job as I've never been really happy with any pass doors I've made.

This was dicussed in a recent thread. Check out certainlywood.com for 1/16" rift oak veneer. If your v groove is large run dadoes in the substrate and glue in solid oak before pressing.
I would go with 1/2" particleboard skins and ladder the interior.

Matth, thank you for for the photo - that looks exactly like what we are looking for.
What did you use to fill the space in the ladder frame? We are trying to figure out if 2 1/4 doors would work, but that one looks the closest and simplest.

Inside the ladder frame was hollow. I had planned to put 1” Ridgid foam in there(for sound dampening), but it got on the way of clamps. I did use stave cores for my ladder framing out of soft maple, and epoxy and domino’s for joinery. The “skins” are wire wheeled pine from the lumber yard, they were lightly sanded then painted for a textured look. Some integrated with existing wall paneling, some were Dutch doors and jambed and cased. These are in a wealthy persons party barn. A lot of open humid air in the summer, and heated dry air I. The winter. It’s been a year and a half since we built them and no call backs yet. I referenced Sochar’s book for construction ideas.

We make plank doors on a regular basis. Agree that if the 8’ tall door has to be 13/4” veneer with in set strips is the safe way. Ladder cores and 1/2” to 3/4” planking require thickness to be successful.
It’s OK to glue the planks to the ladder frame or ply core. Just don’t glue the planks together into one panel. Glued individually they can expand and shrink within their width. I leave 1/16” plus between the planks. Dry here and most everything shrinks. In a wet climate more gap would be required. Yours is interior so that makes things easier.

Just finished this hand planed distressed door for a hike in - skin in small cabin at timberline. 2 1/2” thick. 1” ladder frame with foam infill. Frame and planks are carefully faced material with grain alternating. The T&G is done at the shaper instead of the moulder to make alternating the grain easier to control I liked BH’s idea of screwing the planks on the exterior side in addition to glue. Don’t normally do this and never had problems with just glue but can’t hurt to add reinforcement to the exterior.
TB3 for everything.
The back door on my house is a 68mm thick plank Euro door with BB 1” fir plywood core made the same way with planks glued individually. All joints are still tight after 22 years. This door is to the weather and west facing. Needs refinish but everything still good.

View higher quality, full size image (960 X 1280)

View higher quality, full size image (960 X 1280)

View higher quality, full size image (960 X 1280)

Lots of good advice in the above responses.
A 1/2” ladder frame will work fine, and 5/8” faces will also be ok. If your wall paneling is 3/4, then the door faces need to be 3/4” to make the t&g look the same. Then your best bet is to build at 2-1/4”
You write as if you are trying to order things to certain sizes from a mill. I suggest you hire a professional woodworker and have him or her make the doors. This centers all the details in his/her shop, and the doors can be built properly.

We are ordering from the mill because we are also ordering paneling from them for the extension with matching T&G wall panels.

However some of the doors are sliding doors and 2 1/4 do not fit the openings (already framed), so I am back at needing 1 3/4 inch thick door.

If the ladder frame 1/2" and 5/8" faces work - that solves all the problems.
I do not have easy access to people who specialize in door construction, but they can build well if they know where they are heading (planning on getting a copy of Mr. Sochar's book for them).

To confirm - 1/2 inch with 5/8th face T&G quartered oak ladder frame would work for (1) sliding doors (both sides paneled T&G), (2) swing doors?

I also need one bifold door - again, with paneling on the side facing the room, but the "inward" can be anything. Can the ladder structure work for a bi-fold?
(And sorry - what does one use for the ladder frame - which wood? and what does one use to "fill in" - i see foamy thingies advised, but I dislike foam in all aspects. What can be used instead?)

Thank you.

The 1/2” thick ladder frame needs to have some nice long tenons, about .150” thick (1/3 the thickness of the frame) and 2” long, to hold it all square.

Plywood should be avoided. It does not have rigidity of hardwoods, and will show. Face the lumber to get it dead flat, then plane to 1/2”

The t&g that is go to 5/8” needs to be planed on the “back” only to preserve the t&g visual placement.

I think you feel you must build the doors as a carpenter would instead of using a competent, experienced door builder, all due to distance. A competent shop can make the doors and ship them to you complete. My shop shipped doors all over the US with no problems.

It is best to use the same species since it will show on the edges.

Thank you very much. I suppose I can bring the doors some distance. But how do you find non-local craftsmen?

My nearest metropolitan area is Detroit. How do I find a reputable door builders? I do need several doors.

Where are you located? I’m in northern Michigan.

Acorn Woodworks is in suburban Indianapolis, and well qualified to do this kind of work.