Home>Discussions>DOORS & WINDOWS>Bifold Door in Existing Opening
5 posts / 0 new
Last post
Bifold Door in Existing Opening

I am installing a bifold door into an existing opening. I just refinished the opening and it is now drywall wrapped and painted. Had I been thinking about it, I would have made sure the opening was the right size, but the plan at the time did not involve a bifold so I didn't bother.

The finished opening is 31 & 1/2 inches (give or take 1/16 or so).

I bought some used doors at the Re-Store and they are exactly 16 inches each.

I had planned on trimming the two outside edges to fit.

My question is: should the trimmed door be the exact size of the opening (31 1/2), meaning i would trim 1/4 inch off each side, or should there be some allowance on each side (if so, how much)? also do I need to allow any space for the hinge, as that would add a 16th or 8th or an inch, unless, as I just realised the hinge is mounted on the back as opposed to between the doors. Which method is recommended?

Lastly, I know I can trim the bottom of the door, how much allowance should I leave at the top and bottom of the door. I don't remember the exact measurment of the opening, but I figure there's probably a X number of inches shorter sort of rule.

I'd appreciate any help on this one.


UPDATE - Bifold Door in Existing Opening

as it turns out, the opening is only 30 1/2 (at it's narrowest point, I did my best to make it plumb).

I figure I'll just trim off 3/8 of an inch of each side of each door so the colonial pattern will stay centered. I'm still wondering if anyone has any suggestions on width and whether the door should be slightly narrower than the opening.

A. Spruce
Re: Bifold Door in Existing Opening

If you're using standard bifold hinges and hardware, the doors will need approximately 3/8" - 1/2" on the hinge side. If using a standard butt hinge, then you'll need the thickness of the hinge plus a little for clearance. Be careful when cutting the sides of the doors that you don't remove too much of the structure or the door won't be able to carry it's own weight, let along the second door that is hinged off of it. If these are a louvered door, then you likely won't have a lot of meat to trim before getting into the slot that the louvers are mounted in.

Re: Bifold Door in Existing Opening

What is the best way to trim 1/8-inch of each long side of two sets of louvered bi-fold doors (I need a total of an inch gone)? Can I hand plane them? What size plane?

A. Spruce
Re: Bifold Door in Existing Opening

You can use a hand plane, power plane, belt sander, router, skilsaw, tablesaw, joiner, etc. It all depends on your skill level and what tools you have at your disposal.

I generally use a skilsaw and cut proud of the line, then clean up the edge with a belt sander. Anything less than an 1/8" can be taken off with a belt sander with a little bit of effort.

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.