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wdatampa

Exterior door rough opening

wdatampa
17 years ago

I am about to frame up a rough opening for a pre-hung, exterior door. It is a French door and has exterior trim preinstalled.

I have things saying everything from the opening should be 2" wider and 2" taller than the measurments of the frame to 1/2" to 3/4" wider and taller... and every combination therein.

Anyone have a standard that works for them?

Thanks!

Comments (6)

  • kudzu9
    17 years ago

    Unless there is something special about this door you're not mentioning, you don't need a lot of room. Part of it depends on your skill. If you make the rough opening absolutely plumb/square, and it's in exactly the right place, you just need enough room to get the wedges in at the side and top. I usually go for about 1/4" all around, but then I'm very accurate...slow, but accurate. If you leave a lot of room around the frame, what goes into the space between the frame and the opening so that the two can be firmly connected, and so that the frame can be accurately fine-tuned?

  • sue36
    17 years ago

    DH does 1/2 on the sides, total. So the RO would be 1/2" wider than the unit measurement. Same thing with height, add 1/2".

  • mag77
    17 years ago

    However you decide to size your RO, remember to add the thickness of the finish floor to the height.

    I make interior door rough openings 2 inches wider and higher than the door, but go to 3 inches wider and higher for exterior openings. I've found that, while interior pre-hung doors are fairly standard, there's a lot of variation in exterior door units and it's nice to have a little more wiggle room for insurance. Of course, you have the door, so you're sure of it's measurements.

    John

  • mightyanvil
    17 years ago

    2" is from the inside of the frame. 1/4 to 1/2" is from the outside of the frame. The plumb of the studs will determine the gap necessary to get the door jambs plumb.

  • sombreuil_mongrel
    17 years ago

    The RO will be in the catalog for the unit you selected. If you haven't selected yet, it would behoove you to do so before framing commences. If in doubt, always leave the opening larger, because it can be "padded in" with additional wood. problems arise with the drywallers trimming the opening flush- add an additional 2x4 to the header with two nails so that if when it's removed after drywall, you have an extra 1 1/2" of drywall to play with on top if you _didn't_ need the extra height. It sucks if the drywall is too short to be covered by casing. This hint is just for narrow casing, as wide trim will cover the margin regardless.
    Casey

  • mag77
    17 years ago

    Casey: >

    Slick trick!

    John