I am installing pocket doors into walls that are 4" thick. What kind of studs should I use?

Standard walls have studs that are 3-1/2" thick. With drywall on either side, a typical interior wall is 4-9/16" thick. If this is what you mean by a 4" thick wall, then a regular pocket door frame will work.

Not much info here but a retrofit of a pocket door is not an easy thing. A pocket door requires a rough opening that is twice the width of the door slab. This space is occupied by the pocket door frame that holds the door when in the opened position and of course the space for the actual door opening.

If your wall is an odd thickness, then it would be best to start with a standard pocket door frame kit and modify it ....if your wall is thicker. Bad news is that if your 4" wall is actually 4" from outside of drywall to outside of drywall then it is too thin to handle a pocket door. The absolute minimum is your typical 4-9/16" wall - anything less will not have enough clearance for the door to slide. If by 4" you mean that you have 4" studs, then all you need to do is to add 1/2" to one side of the pocket door frame.

This message has been edited. Last edited by: Jaybee,

A normal wall is 4 5/8 inch thick with a 1 3/8 inch thick interior door (pocket or otherwise).

Subtracting 5/8 inch of thickness from both the wall thickness and the door thickness, you'd think you SHOULD be able to fit a 3/4 inch thick door inside a 4 inch wall using the same pocket door hardware. That is, for your door slab you'd use a piece of 3/4 inch furniture grade plywood instead of a 1 3/8 inch thick hollow core door slab.

The difficulty you may have there, however, is finding a pocket door track and hangers suitable for a 3/4 inch thick plywood door.

K. N. Crowder Company is probably the biggest name in sliding doors in North America. Here are the installation instructions for installing a Crowder Type C pocket door:

http://www.kncrowder.com/.../T...NSTRUCTION_SHEET.pdf

Maybe contact Crowder and see if you can use these same instructions, but with the hardware for 3/4 inch BYPASS sliding doors where appropriate instead to install 3/4 inch pocket doors in a 4 inch thick wall.

(I'd like to know how you ended up with a 4 inch thick wall in the first place? I'm guessing 2X3 wall studs with 5/8 inch fire stop drywall on both sides?)

Thank you.