How Do You Install a Double-Hung Window?

Double-hung windowsIt is going to take some work to install a double hung window. It can easily be accomplished in a day, but not without some prior planning. This kind of job is much easier with an extra person to lend a hand. So make sure the day chosen for the project is one with plenty of time and preferably an extra set of hands. Whether installing in a new house or replacing an existing window, there are four basic steps to follow.

Get it All Together

Before beginning any project, it is imperative to understand the process and materials involved. It is certainly true for window installation. First find the required tools. This job will require basic carpentry tools such as:

  • Hammer
  • Prybar
  • Saw
  • Level
  • Carpenter’s Square
  • Caulk Gun
  • Measuring Tape
  • Power Drill/Screw Gun (Possible if installing aluminum framed windows)

Next, measure the hole for the frame and order the correct size window. It is a good idea to order enough in advance for the window to be assembled and shipped. Many widows must be custom built to the buyer’s specifications and take some time to deliver. With that taken care of, pick out some trim to go around the new window. While at the hardware store grab some caulk, nails (or screws), flashing, shims and insulation. Now that all of the preparation is out of the way pick a day to do the installation when there is ample time to complete job.

Setting Up the Site

Once all the materials are on site, begin by preparing the hole to accept the new frame. If it is a new home, most of the work is already done. If replacing a window now is the time to remove the old one. Begin by removing the trim boards both inside and out. Then the wall outside must be stripped all the way to the studs, in order to remove the nails or screws which hold the frame in place. Now ease the window frame out of the hole to the outside. Before moving on, check the hole to make sure is square. If the top, middle, and bottom measurements vary too much, cut some scrap pieces of wood and nail them in place to get it within the margin for error, according to This Old House.

Fitting the New Frame

The hole is ready to receive a new window. Fit the frame into the hole loosely and check all four sides with a level. Insert shims as necessary until the new frame is centered and squared. Now nail or screw the frame securely into the wall on both sides and the top. With the frame secured caulk around the joint between the frame and the wall. Newer composite and aluminum frames have a nailing fin. If this is the case, use nails or screws to attach the window to the studs from the outside. It is a good idea to go ahead and caulk the corners of the frame as well. Make sure all the joints around the frame are sealed before moving on.

Weather Proofing the Window

Now that the window is snug in its new home, it is time to worry about the weather. The first step is to seal the boards to prevent water damage. If there is enough room, 6 inches or so, this can be accomplished using adhesive waterproof membrane. Don’t worry if there is not enough room to use the membrane. Simply cut flashing to fit cover area between the frame and wall cover then caulk around the seams. Now it is time to move back inside. The area between the frame and the studs must be insulated to prevent drafts. Whether you go with spray foam insulation or fiberglass, follow the directions and fill the area completely before closing it in with interior trim. Once the trim is installed caulk the joints to ensure a good seal.

Related Resource: How To Install an Awning Window

Now all that remains is to install the sashes as per the manufacturers specifications. Ok, so it is a lot of work, but the result is worth the time and effort. The newly installed window will not only look better but will help to save on heating and cooling costs as well. Now that the work is done sit back and take pride.