Building a Garage 8 - Windows Building a Garage 8 - Windows

Intro - Materials - Foundation - Laying Wall - Positioning/Framing - Roof Framing - Sheathing - Windows - Siding/Soffit - Felt/Asphalt

Checking the Window and Rough Opening

Most Common Mistakes:

  1. Improperly ordered window
  2. Damaged window
  3. Window will not fit


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1. Upon arrival of the windows and doors, uncrate and check for any damage that may have occurred in shipping.

2. Make certain the manufacturer's installation instructions are with the windows and doors.

3. Check that the window is, in fact, square by measuring diagonally from the upper right corner of the window to the lower left corner of the window. Then measure from the upper left to the lower right corner. if these measurements are exactly the same, your window is square. Make certain that all of the parts are there and that it opens easily, correctly, and from the specified side. If diagonal braces are attached to the window to keep it square, leave these in place until the window is installed.

4. Check the rough opening to be sure it is square and of the proper dimensions. If sheathing overlaps into the opening, cut it out with a hand or power saw.

Installing the Windows

Windows are installed either before or after the siding depending upon the type of siding used.

Most Common Mistakes:

  1. Not using shims to level and plumb
  2. Not caulking
  3. Installing windows upside down
  4. Not leveling properly
  5. Trim not flat against sheathing


  1. Run a bead of silicone caulk on the backside of the exterior trim to protect against water and air infiltration.

  2. Place shims every 16 inches on the rough sill to be used in the final leveling of the window. Then set the window unit in place from the outside of the garage.

  3. Use your level to check that the window is level and plumb. Make certain the trim is flat against the exterior siding or sheathing and that the jamb is the proper thick- ness for the wall. Check that the flashing overlaps the top (horizontal) trim piece. If the window is protected by roof overhangs, flashing can be omitted.

  4. Have someone press against the trim to keep it flat against the siding as you nail. Insert shims every 16 inches around the window and nail through the jamb and shim into the studs. Use 12 or 16 HDG finishing nails and countersink them with a nail set. Then nail the exterior trim with the same nails.

Intro - Materials - Foundation - Laying Wall - Positioning/Framing - Roof Framing - Sheathing - Windows - Siding/Soffit - Felt/Asphalt

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