DIY Window Surround

Stock window molding is the most common material used to fabricate a window surround, but you can trim your windows with ordinary lumber and embellish it any way you like without mitered corners. Window surrounds are not part of the structure; they are decorative, which gives you a lot of freedom. The trickiest part of trimming a window is cutting the materials accurately. Precision is quite important if you will stain the wood, as gaps and uneven cuts will stand out. If you prefer painted molding, latex caulk can effectively fill and disguise imperfections and gaps.

Measuring tape
1-by-4-inch lumber
Pencil
Miter saw
Level
Finishing nails, 4d and 8d
Hammer
Nail-set tool

Instructions

- 1
  Measure from the top of the window stool at the left side of the window to the upper-left corner of the left window jamb. The stool is what many people call a windowsill. It is the flat, horizontal section that acts as a ledge across the bottom of the lower window sash. The jamb is the frame or housing of the window sashes.
- 2
  Measure a 1-by-4-inch board to that length plus 1/4 inch and mark it on the edge with a pencil.
- 3
  Set a miter saw’s blade to zero degrees, vertically straight.
- 4
  Place the marked board on the saw’s platform with the pencil mark centered over the platform opening. Lower the saw’s blade without engaging it and adjust the board left or right until the blade is aligned with the mark.
- 5
  Hold the board firmly against the platform with your hand away from the blade path. Raise the blade, engage it or turn on the saw, lower the blade and cut the board at the mark.
- 6
  Measure, mark and cut another board for the right side of the window.
- 7
  Stand one board upright or vertical on the window stool at the left side of the window. Align the right edge of the board with the left window jamb. Move the board slightly to the left to reveal approximately 1/4 inch of the jamb.
- 8
  Place a level against the left side of the vertical board. Adjust the board as necessary until the bubble is centered and the board is plumb or vertically straight.
- 9
  Fasten the board along the edge of the jamb with 4d finishing nails and a hammer. Space nails approximately 6 inches apart up the right side of the board. Repeat with 8d finishing nails along the left side of the board to fasten it to the wall. Do not hammer the nails flush with the board, which can cause damage. Leave a small amount of the nail heads raised, then tap them below the surface with the pointed end of a nail-set tool and a hammer.
- 10
  Mount the second board at the right side of the window in the same manner.
- 11
  Measure from the left edge of the left vertical board to the right edge of the right vertical board. Measure, mark and cut another board to that length.
- 12
  Set the board horizontally across the top of the window, resting on the upper edges of the two vertical boards that you mounted to the wall. Fasten the board to the wall as you did with the vertical boards.

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