Stating Dimensions for Crown Moulding

Crown molding sizes can be looked at two ways: The thickness and width of the board, or the vertical and horizontal distances it will span when installed. Depending on the situation, either could be important. December 2, 2006

I've been working with wood for 30 years and I've pretty much been self-taught. One of the drawbacks of that is that you don't get to draw on other's knowledge very often. Here's my question: how is crown moulding sized? I have heard one size called: 2 5/8, 2 3/4 and 3". Is it measured point to point or is it measured from ceiling to bottom of moulding as it is installed?

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor J:
Point to point.

From contributor W:
Height and projection.

From the original questioner:
Okay, who's right?

From contributor B:
When you have one size given (example 4 5/8), it is always measured point to point.

From contributor E:
The place I buy molding from is a pretty good sized operation and they give two measurements. Thickness and point to point.

From contributor R:
All posters are correct in their answers. Point to point is used more often when ordering, manufacturing, or selling. Height and projection are more commonly used by drafting, architects, and design people. The height and projection set the width. The width and back bevels set the height and projection. It depends on which is more important to you and your project. Good question - in this case, everybody is correct.

From contributor F:
That is a good question. As an end user of spring moldings, I can say that what matters most to me is the dimensions of the molding in both height and projection. I need to know those two dimensions in order to design my work. For instance, when the crown molding on one cabinet terminates into the side of another cabinet, I need to know the projection of the crown so that the side of the cabinet is deep enough for the crown to terminate, plus a reveal margin. One thing that would be of interest to us all is the correct order of the three dimensions when all three are given. Is it projection x height x point to point?

From contributor R:
In most catalogs you will only see thickness and width (point to point 3/4" x 4 1/2", etc.). However, for master craftsmen, the height and projection I think is more important for reasons you mention. That's why I list both (at - it just depends which dimensions are more important to you. I don't believe there is any correct order in which to list them other than thickness X width.

From contributor B:
Letís look at it another way. Solid crown is sold by its thickness (ceiling projection) and width (wall projection). The size of the board determines the price. A sprung crown is also sold by its thickness (which is not the ceiling projection) and its width (point to point, which is not the wall projection). Again, the thickness and the width of the board determine the price. This is what is important to the manufacturer. It is important for the installer to pick a ceiling projection (I say pick, since you can alter it a little to adjust for reveals, etc.), since knowing the ceiling projection is the only way to check your miter cut depth before you cope. The miter cut depth on your piece to cope, has to equal your ceiling projection. You can use a framing square to check it.

From the original questioner:
Thanks for your responses. They were very helpful. I am buying a small moulding machine soon and this info will be very useful.