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sarabelle80
exterior door with 4" door jam
sarabelle80

Hi, I have a "Michigan room" off the back of the house I just purchased. It has a exterior out-swing door that I really dislike. I would like to put a regular steel in-swing entry door in its place but cannot find any door with a 4" jamb. Without having much knowledge of manufactured home doors, does anyone know if their door jamb is smaller or is it the custom 4 9/16"? Does anyone have any suggestions?? (Maybe an adjustable door jamb?)

A. Spruce
Re: exterior door with 4" door jam
A. Spruce

Everything "trailer" is an odd size, even within the trailer industry there is very little "standard". This is how they keep you captive and charge you 3X the price for replacement parts and pieces.

You do not need to get a custom width jamb, while I'm sure you could order such a beast, it isn't necessary. I would install a standard, off the shelf door used in a standard stick framed home, yes, the jamb is going to be 4-9/16", the fix is that you simply shim the back of the door trim on the inside. That is to say, you install the door flush with the exterior surface and let the inside stick into the room. Then you install trim to the wall around the door frame, then you install the door trim on top of the whole works. You have two choices here, the shim trim can either be significantly wider and a visible component to the door trim OR you can make it flush with the outside edge of the door trim and not see it at all.

I personally would install the shim behind the trim so that it couldn't be seen, and I would do it after I installed the door trim, so that I could easily flush it with the edge of the door trim. I described it differently above to make it clear as to what I was talking about.

sarabelle80
Re: exterior door with 4" door jam
sarabelle80

Thank you for your help!

So I have this straight (CDO here too)

1. Install trim around door opening
2. Install door
3. Shim
4. Door trim to cover shim and make it look flush against first trim..

A. Spruce
Re: exterior door with 4" door jam
A. Spruce

1 - Interior/exterior trim comes off existing door. Cut the fasteners holding the jamb in place with a sawzall and work the jamb out of the opening. Clean up any debris, in the jamb or on the threshold.

2 - Install new door and jamb into the opening, taking care to get it plumb and square, place shims between the jamb and framing to keep jamb straight when you install your fasteners. The new door needs to be flush with the exterior wall so that you can reinstall the trim properly. You will also want to put a bed of silicon caulk on the sill before setting the door into place to seal the threshold. With the door in place you will also want to spray foam around it, sparingly, to seal the gap around the jamb. I say sparingly, as you only need just enough to close the gap, too much and the expanding foam will move the jamb and cause problems.

3 - Install trim on inside of door, nailing to door jamb only. Measure and cut the shim to fit between the trim and the wall, then carefully slip it into place so that it is flush with the edge of the trim, nailing as you go to keep it in place.

4 - Caulk with a good latex caulk inside and out along all joints, paint, pull up a chair and admire your work.

FYI, it will take an experience installer about 2 - 3 hours to do this job, it will take you 5 - 6 hours to do it, so be prepared. You will also want to have EVERYTHING you will need before you start, once the door is out of the wall you won't be able to make material runs.

Mastercarpentry
Re: exterior door with 4" door jam
Mastercarpentry

I take a different approach when shimming interior trim like needs to be done here. Install the door, lay a straight-edge across it and measure to the wall in several places, find the median measurement (or the taper if angled a lot) and remember it. Cut the casing trim to fit, dry-fit it to be sure it's right, then cut strips to your median measurement or taper. Leave them long, then glue and pin them to the back of the casing on the bench where it's much easier to keep the edge perfectly flush. Now trim the ends off on your miter saw to match the casing, then install as normal. You do need a pin nailer and compressor for this which every DIY'er will not have, but if you do much woodwork it is a tool well worth having and even the cheap ones from Harbor Freight etal do a decent job.

Phil

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