Replacing old windows with newer and more efficient ones can lower your electricity bill and lift your house price. And this can be even more profitable if you decide to save on workforce and install them on your own. For those not afraid of working with their hands, here is an instruction on how to install replacement windows all by yourself. And if you need help or a piece of advice and ask yourself, “How do I find window pros near me?” this article will help you.
Full or Partial Replacement?
First of all, you need to understand if you need a full-frame replacement or just put in replacement windows. The first option is much more difficult and requires you to remove both inner and outer trims and replace them with new ones. This is necessary only if there is a problem with the existing frame or you are looking for a complete makeover. The second one is much easier as you will only have to replace the sashes. In this case, there won’t be overcomplicated disassembling.
Measure for Replacement Windows
To get the right sizes to make measures inside the existing frame, a tape measure will come in handy. When you measure the height, do it in the left and right corners and also in the middle. When measuring the width, take the same approach — first the corners, then the middle. Use the smallest of the measures you got to order the window. Don’t do any further work until it arrives as you have to make sure that it fits before moving forward.
Removing the Old Window
The steps may vary for different mounting systems and houses of different ages. Yet, here are the steps you’ll generally have to take:
- Removing the storm windows. It’s either done by simply lifting them from their mounts or unscrewing bolts that hold them in place.
- Removing the frame. This will require you to score a window edge first, then remove the screws, and, finally, pry it open with a crowbar or knife.
- If there are sash springs or weights, remove them next.
- Removing stops. In some cases, you can pry them off, but if they are embedded within a frame, you’ll have to use an oscillating saw.
- Prepare the surface for new windows. Fill any holes with a special wood filer and check if the wood holds well. You’ll have to remove any rotten areas before proceeding.

Installing the New Window
Here is what you’ll need to do:
- Clean the opening from dust and debris.
- Fill the length of the sill with flashing tape.
- Check if the sill is leveled.
- Apply silicone caulk to the top part of the frame, the stops, and the sill.
- Place the new window in the opening. Push it firmly against the caulk and the interior stops.
- Check if the sashes sit evenly in the frame.
- On the outside, fill the gaps around the window with insulation.
- Drill weep holes at the bottom of the adapter for water draining.
- Install interior trim.
- Complete the installation by applying caulk to the interior trim.