How to Easily Master Window Framing
When you are building your house there will be places in the walls were you will want to install windows. In order to do this, you will have to frame an opening in the wall that will accept the window unit when you reach that point of the construction project. Unfortunately, you cannot simply cut some of the studs in an existing framed-up wall and put in a window, without some modifications. But with the proper knowledge of window framing requirements, you can move or add a window almost anywhere you desire.
Window framing has its own terminology, which you should be familiar with, in order to talk intelligently with your contractor or other DIY’s. We’ll introduce you to jack studs, king studs, (sorry, no queen studs, but that may be an oxymoron anyway) rough openings, and cripples. (An actual framing term, but every person with a leg problem should be referred to as physically disabled or challenged, not crippled, just to be clear)
In order to properly frame a window opening, you first need to determine where the opening needs to be and the size of the opening. The rough opening is the hole in the wall framing, into which the window unit will be placed. It should be constructed so the top, bottom, and side measurements are about ¼” greater than the actual size of the window unit. This is to allow for final adjustments (adding shims where necessary) of the window unit to ensure that it is plumb, level, and square.
Start by determining exactly where in the wall the window will be placed. Position one stud on each side of the rough opening, 1 ½” to each side of the finished rough opening size that you require.* These are your king studs, because they go from the floor plate to the top plate. Leave everything unnailed at this point so you can make any adjustments before you nail it together.
Measure the distance that you need for the top of the rough opening, from the floor, and cut 2 studs 1 5/8th ” less than this length, (which allows for the floor plate dimension). These are your jack studs which will hold up the header. Make your header for the opening out of 2 lengths of 2-by lumber, of a width in inches equal to the span of the window opening in feet, (or a minimum of 2×6 material) spaced with plywood to make the width of the header equal to the width of the walls studs. Nail the jack studs to the king studs and place the header on top of the jack studs and everything into place. Insert short studs into the space between the header and the top plate with the same spacing as the rest of the wall.
Once you determine what the height of the window opening from the floor needs to be, cut short pieces, these are your cripples, (seriously) 3 1/8th” shorter than the bottom of the rough opening. Nail 2 of the cripples to the jack studs to support the sill plate of the window opening. Cut the sill plate to length and nail it to the cripples underneath it and then position the rest of your cripples under the sill plate at the same spacing as the suds in the rest of the wall.
of building a hole.