How Are Windows Replaced?

Basics of the window replacement process

Replacing Windows In a Home

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Installing new replacement windows is such an expensive, time-consuming process, most homeowners go through it only once or twice in their lifetime. So it is normal to wonder—or to forget—what happens during the window replacement process.

A generalized chronology of the replacement process begins even before the installers arrive, when you get your house in order.

Before the Window Installers Arrive

While it's possible to do nothing to prepare for the window installers, you make your life easier—and potentially smooth the way for a higher-quality job—when you prepare your household in advance:

  • Touch bases with the salesperson or scheduler and confirm the installation date and time.
  • If you have unique needs for certain windows (such as saving an antique leaded-glass window), tape notes on them.
  • Arrange for pets to be cared for at a separate location during the replacement process.
  • Same with children: Small kids roaming during window replacement not only get in the way, but they can also become injured.
  • If you can take off time from work or can work from home, do so. If you work from home and have a home office, ask if the crew can do that room first, allowing you to get on with your work.
  • Add drop cloths outside if you have flower beds that you wish to preserve. Inside, dust barriers might be set up, but this is not really necessary, as window installation does not create much dust.


Pay attention to the weather forecast in your area, and reschedule your window replacement if necessary.

How Windows Are Replaced

  1. Preliminaries

    Meet the job lead person and walk through the house, going over each window. This is your chance to catch any errors the window company may have made in ordering your windows. If this is a multi-person crew, one set of installers will bring in windows as another set of installers removes windows. Walk through the house on your own to ensure that the installers have laid down drop cloths to your satisfaction.

  2. Old Windows Are Removed

    If the work crew is large enough, some team members will precede with removing windows, while the other members will follow up by installing windows. Ropes for the window sash weights are cut. Weights drop to the bottom of the window pocket. New windows are set in place and leveled with shims. With the window level, it is nailed into place.

  3. Old Windows Are Moved Outside

    As installers periodically move old windows outside, the stack of old windows grows. If you are saving the windows for yourself, it's a good idea to periodically move them away to give the installers room to work.


    The installers are now fully engaged in removing and replacing windows. There is little need for supervision, but it is always a good idea to touch base with the project lead person.

  4. Project/Day Complete

    Many window installation projects can be completed in one day. If not, work may spill over to a second day. In most average-sized houses, the second day concludes the window installation process, with little need for a third or subsequent day of work.

    If the project does not wrap up in one day, the crew will make sure that the house is back in reasonable order for the night. Depending on the size of the installation crew, by the end of the day, you might expect 12 to 15 windows to be removed and replaced. Most window technicians will leave old windows either in-place or replaced with new windows. No tools should be left in your house. Rooms should be broom-clean. Old windows outside should be removed.

  5. Removal and Installation Continue

    Installers arrive early and continue removing and installing windows. When the removal team is finished, they begin installing exterior trim on your windows. This exterior trim, or cladding, provides a tight seal against the weather. Depending on your contract, this service may be optional.

  6. Windows Are Tested

    The house is broom-cleaned and windows are tested by opening and closing them. Often, labels are left on the windows since they contain warranty information. If the crew does remove the labels for you, ask them to save the labels for you.


    If the window replacement process does extend into a third day, the reason may be to finish installing the exterior cladding. You will not need to be present for exterior work, though if you have the time available, it is always a good idea to be around.

  7. Followup Call or Visit

    Many window companies will follow up a finished project with a call or even a visit to make sure that the customer is satisfied with the work. This is the best time to bring up any concerns, either with the work or with the materials.

Tips for When Your Windows Are Replaced

  • The best way to manage a window replacement work crew is to not manage them. Trust the company that you have chosen to do its best possible work and stay out of its way. Choose a room that's not part of the project and camp out in there. If necessary, take the dog for a walk or go to a local coffee shop until a room in your house opens up.
  • Providing a crate of sealed bottled water is often appreciated by work crews. But you're not expected to provide meals or any type of food service. Most workers bring their own lunch or go out to grab something.
  • Be within calling distance if they have questions, but do not hover. You get the best results if members of the work crew can call on you as a resource, without you constantly hovering over them.
  • Small items of value should be locked away in a cabinet. Move large items. Cover large items of value that cannot be moved away from the windows.