How to Add a Dormer Window
A window can be added to any wall in a house including a dormer that is either original construction or added later. A dormer creates additional space in a roof of a building or home by adding needed headroom. Dormers that are added to a home can have windows installed that will add to the look of a home. A window can be added to a dormer by following a few steps to mount the window in the wall.
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Things You'll Need
- Pencil
- Tape measure
- Straight edge
- Circular saw
- Reciprocating saw or Sawzall
- 2x4 lumber
- Hammer
- Shims
- Level
- Drill
- Foam insulation
- Caulk or sealant
Instructions
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1
Measure the dimensions for the new dormer window with a tape measure. Use a straight edge and a pencil to mark the window opening on the wall. Mark the opening on the inside as well as the outside of the dormer.
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2
Use a circular saw to cut the drywall for the inside opening.Place the saw so that the blade is on the inside edge of the pencil mark. Pull the trigger on the saw and make a cut on each line.
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3
Remove the piece of drywall to expose the inside of the wall. If there are any studs in the opening they will need to be cut with a Sawzall. After the studs have been cut use the Sawzall to cut the exterior window opening.
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4
Construct a frame for the window using 2x4 pieces of wood. Measure the width and height of the opening from the edge of the drywall. Mark out pieces of 2x4 lumber and cut the lengths that are needed. Place the shorter pieces inside the longer pieces to create a square or box shape. Put two framing nails in each corner to secure the frame together. Place the frame in the opening and secure it to the studs with framing nails.
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5
Insert the window into the new window frame in the dormer. Place shims between the window and the frame to level the window. Tap the shims into place using a hammer.
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6
Place a level on the side and middle of the window to see how level the window is in the frame. The window can be adjusted by adding or removing shims until the bubble in the level indicates that the window is centered.
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7
Secure the window to the frame using a drill and screws. The window should have two to three opening for screws on either side. Place a screw in the opening and tighten it with the drill.
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8
Fill in the gaps between the window and the frame with foam insulation. The foam will expand so leave enough room or some will need to be removed after it dries. Place trim around the frame and the wall to finish the look.
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Tips & Warnings
A screwdriver can be used to tighten screws if a drill does not fit. Use a utility knife to score and break off the shims. The window measurements should match any standard size window. A custom size window will need to be special ordered from a home improvement store. A replacement window will be easier to install than a new construction window.
Always wear eye protection when using any type of saw.
