Measure the inside dimensions of the garage door jamb horizontally across the top and vertically along both sides.
How to cut garage door trim.
Set the power miter to a 45 degree angle.
Measure across the top of trim on the outside of the door from the outside corners of both pieces of vertical trim that you just nailed on.
Step 1 remove old trim.
Make a mark before you cut another 45 degree miter with the power miter.
Step 2 cut your trim to size.
How to trim a garage door opening 1.
Then measure the length of the moulding from the inside point of the miter you just cut to the desired length.
Cut the first miter on the head moulding piece.
If you currently have trim around your garage door you will need to remove it before installing the new trim.
How to install trim around a garage door opening.
Cut a piece of trim to that measurement.
Measure for the brick molding the trim that will face the street starting with the top piece.
Learn how to install our vinyl thermostop garage door trim.