No weird angles or expensive rosettes to buy here. Just cut the two vertical side pieces of casing so that they reach (but do not extend beyond) the top of the door opening.

Then cut a header piece (the horizontal top piece) so that it equals the horizontal door opening + the twice the width of a side casing + plus some whatever extra amount that tickles your fancy.

Butted door casings have a utilitarian look that can look cheap.  So, use real moldings, not dimensional lumber (i.e., 1×4s).

By that last time, I’m talking about the extra amount that extends beyond the side casings. It can be anything you want, but you’ll probably not want to go crazy here. This is all for show, and gives your butted door casing a little fancy finish: a quarter-inch on each side is enough.

Admittedly, mitered casings are not too hard. For goodness sake, it’s just a 45 degree angle cut.

But for some reason, those mitered casings sometime go wrong. Something is out of square—the door framing, your brain, or something—and those two angles just don’t come together.

Butted door casings save you from all that. The horizontal and the vertical door casings meet at a 90 degree angle. Except, of course, there is a blank space where they are supposed to meet. Hard to describe, so look at the image above. So in that blank space you drop a corner block, or rosette. Rarely do you have any gaps with this butted door casings plus rosette design. Terminology: this isn’t really a true butted door casing—that’s another thing we cover—but it’s just what I call it.

But, yes, like anything, there are some drawbacks with the butted door casings plus rosette design:

• Those rosettes can be expensive.
• This style tends to be more classic and traditional. If you have a contemporary style house, this may not work.

Storm Door is Not a Storm Window

One problem seems to be that houses often have storm windows, and these storm windows are temporary things that go up in the Fall and come down in the Spring. Storm windows are designed to provide windows with extra protection during harsh weather.

But storm doors do not come off. They stay in place, year-round. They are a completely different animal than storm windows.

Why a Storm Door Should Be Everywhere

Exterior access doors are expensive and very hard to install. Despite your climate, exterior doors always get a beating. If it’s not snow, then it’s sun. If it’s not sleet, then it’s tropical rains.

The main argument for installing a storm door is that it greatly extends the life of your exterior access door. I estimate that a storm door will triple the life of your exterior door.

No. You’ll need to plan your door installation just as you plan other aspects of your home renovation. I shouldn’t have to tell you why, but here’s one “why”: doors are forever.

Whereas you can rip down that bum crown molding and replace it (not likely, but whatever), it just ain’t gonna happen with a door. So here are some rules of thumb about planning a door installation that you had best heed:

• Width and Thickness of Exterior Doors – How wide are exterior doors? How thick? This measurement can vary, but think of 36 inches wide and 1.75 inches thick as being standard measurements. Now, the 1.75 thickness is for the door, not the door frame.
• Width of Interior Doors – Sizing is less important for interior doors, because we don’t have emergency egress to worry about. Look at 32 inches as a good width for interior doors
• Height of All Doors – For either interior or exterior doors, 80 inches is the standard height.