A man replacing a window in his house

How to Install a Replacement Window Yourself

Tips for Replacing Old Windows

Spring is finally on its way, and with that warm weather and fresh air you may be considering new windows. But do you know how to replace windows? Before you head to your local window dealer, you should ask yourself some questions.

Are you replacing inefficient windows? Are you remodeling or updating your home? Has the wooden frame rotted away? Your answers will help determine the kind of window you need, and what the installation process will be like.

Vinyl or Wood Replacement Windows

If you are replacing a drafty window, then you must decide between wood replacement windows or vinyl. Both styles are energy star rated and can increase the comfort and value of your home. The two primary deciding factors are price and appearance.

Many people prefer the appearance of wood windows, but they can cost almost double that of vinyl windows. If your neighborhood is full of vinyl windows, your new wooden windows may be out of place. Always weigh the pros and cons of each option before making a final decision.

How to Measure Windows for Replacement

Once you have decided on a material, it is time to measure your windows. For an accurate width, place one end of the measuring tape on the jamb on the left side of the window, and measure all the way to the right jamb. For the height, measure from the sill to the top jamb, and make sure to keep the measuring tape plumb.

It is important to take several measurements of the width and height to ensure the window hasn’t bowed. If it has, use the smallest measurement when ordering a new window, as the gap can be filled more easily than having to enlarge the opening.

If you decide to purchase a window from a big box retailer rather than from a window specialist, be certain to purchase a replacement window (also known as a pocket or insert window). New construction windows are installed from the outside. If you are uncertain about how to measure windows for replacement, you should contact a professional.

How to Replace Windows

Wood and vinyl window replacement is done the same way and can be completed by a professional or homeowner. Should you decide on a contractor for your new window, it is still valuable to know how to replace windows.

First, carefully remove the trim and window stops with a utility knife. You will reuse these parts after the installation. If you’re replacing a window with sash cords, chains, or weights, carefully remove those as they may contain lead. Afterwards, remove the parting beads (vertical strips that help move the sash) and finally remove the sash.

Before doing anything permanent, place the wood or vinyl window replacement into the opening to check the fit. Shims, caulking, and insulation can all be added to help the window fit tightly into the opening.

After testing the new window, run a 3/8″ bead of caulking along the sill before inserting the new window. Check that the new window is square. If not, use the shims provided by the manufacturer to move the window into place. Then, simply screw it into place.

New Construction Window Installation

New construction windows offer the same styles as replacement windows. When installing from the outside, it is important to make sure that the new window will be waterproof with a self-adhering membrane.

Measuring for the new window is similar to replacing a window, except that the new window must measure .5 – .75 inches smaller than the rough opening.

Whether you’re installing from the outside or replacing an existing window, it is important to measure accurately and seal everything appropriately against the elements. If not, the window will be more difficult to install, and it will be drafty or leaky, which defeats the purpose of a new window.