How to Install a Window: All the Steps Made Simple

How to install a window?

There are many reasons to install or replace a window. Different windows can help with different issues even. Installing a window doesn’t have to be a monumental task.

Below is a step by step instruction on how to install a window. Follow these steps and you’ll be cozy and comfy in no time!

Tools for the Job

Before there are any holes in the structure it’s important to gather up all the necessary tools that will be needed to complete the job. 

Like a cook preparing ingredients, it’s important to have all pieces of equipment needed or a window replacement could be a long and frustrating process. 

For quick, painless window installation, make sure to have a power drill with additional sized drill bits, a circular saw with blades, a hammer, a level, a caulk gun with caulk, a utility or box cutter knife, a putty knife, tape measure, and a level. 

It is also recommended to have a drop cloth for debris, as well as safety glasses and gloves to protect yourself from any jagged edges. Small wooden shims are highly recommended to hold the window in place when applying caulk, but they are not required. 

How to Install A Window

Installing a new window can seem like a daunting task. Windows come in a variety of shapes and sizes, with everything from simple panes of glass, to double glazed windows!

No matter what design you are looking for you can find a window to fit your style! You can even impress everyone by following these steps to install a new window. 

Remember to measure the window opening. Take measurements of the width and height around all sides of the window casing. Make sure that the window bought is about 3/4 inch smaller than the window opening. This is so the window fits perfectly and doesn’t need to be reframed in the wall. 

Step 1:

First, it is important to remove any dust and dirt. A simple vacuum will work. After cleaning up, set down the drop cloth and gloves, and grab your hammer. 

The existing window casing must be removed first. Use a pry bar and hammer, or a flat-head screwdriver and a hammer to pry loose the existing window casing.

If you are not replacing a window, please skip to step three after vacuuming the area.  

Step 2:

Once the window casing has been removed, it is time to remove the existing window from its housing. 

To do so, the window jamb must be found, typically this is on the top or sides of the window. If broken or rotten a new jamb will be needed.

After removing the window, check for any damage to the window casing. Repair any holes with caulk and double-check measurements for a new window. 

Step 3: 

Now it is time to test the window.

Once you have made sure the window fits, the window can be placed in its housing, with wooden shims around the top, bottom, and sides of the window. 

The window should sit level. First, check with a level that the window is sitting level in the housing. 

Step 4:

Next, the window must be measured again.

Measure the window diagonally from the top corner to bottom. If properly level the two diagonal measurements will be equal. By checking the diagonal measurements you make sure that the window is sitting perfectly straight.

If not done, the window could allow wind, water or any other outside pollutants inside.  

Step 5: 

The window should now be level and in the window housing. 

Next, a circular saw will be needed to cut the wood that will surround the window. This will create a new window siding. 

Depending on the size of the window and the style, each cut will be different. It’s important that the circular saw’s blade depth matches that of the thickness of the siding. 

Make sure that the wood fits flush with the wall and the window casing. This will make sure that the window sits flat in the wall and doesn’t look unprofessional. 

After all the necessary cuts have been made and the wood is in place, the wood and window casing must be caulked together. This will prevent damage from the outside, and make sure the window remains exactly where it was meant to be.  

Step 6: 

The hard part is over!

Now, the window can be placed in. The window will slide into the casing, and should be pressed up against the caulk.

The window casing will have pre-drilled holes where shims should be added. Find the pre-drilled holes, and drill the shims into place. 

After the window and shims are in place, double-check that the window is still even and level. 

Step 7:

Now the window is in place! 

The shims will probably be bigger than needed. It’s important to score the excess with the utility knife and break the excess off. 

After that, check for gaps between the window jambs and the framing. Fill ALL holes with fiberglass insulation to ensure a tight and draft-free fit. 

Step 8: 

Caulk any holes that may still need to be filled and allow the caulk to dry. This could take up to a day in some cases so it’s important to be patient until the caulk is absolutely dry. 

The only thing left to do is to paint around the window. The window is in and will be yours to clean and decorate as you see fit!

Can You See It Now?

A window will typically last between 20-40 years.

How to install a window? A window can be installed in as little as a day. 

The home of your dreams is closer than ever. If you were ever curious about how to install a window and thought it was too difficult for you than think again! 

By following the above eight steps above you too can install a window!