Once you have determined that you will be installing your own window trim, your next task will be to determine the material that you will be working with. While wood is perhaps the most common material used for this purpose, stucco window trim is becoming increasingly popular in homes due to its luxurious and detailed appearance. Stucco is lightweight and designed to withstand both very high and very low temperatures, making it a very versatile material. Though working with stucco window trim is a very manageable job if done correctly, there are specialized techniques and tools required to do the job.
Step 1: Measuring Window
For any job of this sort, measuring the window frame itself will be extremely important to your finished results. Measure each side of the window as well as the top and bottom to within an eighth of an inch (1/8"). Adding 1/4" to each measurement will allow you to create a visually interesting reveal of 1/8" on each side when you install each section of trim.
Step 2: Cut Window Trim
Use a miter saw to cut the end of a length of the window trim you've selected at a 45 degree angle. Measure from the shorter edge of the angle you just created. Measure the proper distance of one edge of the window frame that you already measured and make a mark. Using that mark as the short end of your next cut, use your miter saw to make another 45 degree angle. Repeat this process until you have 4 sections of window trim cut with 45 degree angles on each end.
Step 3: Prepare Surface
Since you will be using adhesive to attach your stucco trim to your window frame, the surface of both the trim and the area to which you will be attaching it must be prepared beforehand. Both surfaces must be clean, dry and the temperature should be a minimum of 40 degrees Fahrenheit. Make sure the surface that you are applying the trim to is both level and planed even.
Step 4: Attach Trim
You will be able to purchase adhesive recommended for use with stucco at your local hardware store. Apply adhesive to the back of one of the sections of trim using a 3/8" notched trowel. After allowing adhesive to become tacky to the touch, affix this section of trim to the window frame. In some instances, you may want to use mechanical clamps to hold trim in place while adhesive hardens. Be sure to remove any excess adhesive from edges of trim before it cures.
With the same technique, attach each of the other three sections of trim to your window frame, using caulk between each miter joint to hold them together.