Bow windows improve the appearance of a house by their classic design and curb appeal. Choosing to create your own bow windows is not beyond the ability of the homeowner who has some construction know-how. This project is best for intermediate to experienced do-it-yourself enthusiasts.
Determine Desired Dimensions
Before acquiring any materials it is important to know the size you wish to have the bow window. Deciding the width of the window, the number of window panes you expect to install, and the depth of the assembly from the wall to the furthest point. Once you have the measurements you need for height, depth and width of the bow window take the measurements to a home store for proper amount of materials. Consider 3 to 5 framed windows depending on the depth and width of your bow.
Create Bow Shape
To create the bows use the 1 by 2 boards. Saturate your wood frames in water overnight and then, using wood clamps, shape both the top and bottom wood frame pieces at the same time, carefully forcing them into a curve without cracking the wood. This bowing process can take several days depending on the size of your semi-circle.
Assemble the Parts
Using the bow as a template mark the 1-inch plywood to cut into the same semi-circle. Mark from the outside of the bow so the wood can be connected. Run a generous continuous bead of wood glue around the edge of the plywood. Attach the bow to the piece of plywood. Wait about 10 minutes for the glue to adhere and then from the bottom side attach the bow to the plywood with 1 7/8 inch nails (or 1 7/8 screws).
Be sure the nails are not too long that they protrude. Follow this for the other bow and plywood form. Connect the framed windows to the bottom plywood frame (keep the bowed wood on the underside) and separate each window with a secure 2 by 4 cut the size of the framed window. Attach each window with wood glue and nails. Attach the top form of the bow window with the bowed wood above the plywood. Wait a few hours for the wood glue to dry well. Attach "L" shaped brackets to windows, pointing inward.
Install Bow Window to Opening
Using a helper or two, lift the window into place. From the inside of the house, attach the "L" brackets to the house. If you wish, more "L" brackets can be hooked to the top of the assembly as well, but 3 on each side should be sufficient. Use 16 penny nails to attach the brackets to the house, or 3-inch wood screws. Use 2 by 4 buttresses to support from under the windows. Paint to finish.