DIY Replacement Window Installation

A DIY replacement window installation is the way to go if you want to save some serious money, I’m talking about thousands. So in the last post we talked about doing a DIY Window Removal. The most essential take away was the simple fact that you have to get to the window sashes. In my experience there weren’t any straight forward videos or How Tos that were available for our specific window design, window stop configuration, etc.

Taking off from where we left off last post, at this point you should have a clear windowless window frame. Use a shop vacuum or a vacuum with a dust filter to clean any excess dust and debris. You can also you use hand broom (you know the little one that comes with a dust pan) if you have one. Before I go any further, let me say getting to the removal step and pre installation, we are assuming you already measured your window frame from left to right and top to bottom. And bought the replacement window.

What is a replacement window?

A replacement window is just that, a replacement. It will fit right into the same opening you removed the old window from assuming you have accurate measurements that are accurate within .5 inches. As you will see when you buy the replacement, it will give you a range i.e., fits openings 29.5-30.5″.

 

What is a New Construction Window?

The other alternative is a new construction window. These windows are designed for a rough tear out where you have literally removed everything to the bare bones even the window sill. New Construction windows come with a nail fin and are install from the outside of the house.

Install that new window

First, check the specs on  your window and measure it a final time before preparing to install. This ensures that it will fit. Let’s just say I learned the hard way last January in freezing temps buying a window right before Home Depot closed, which meant I couldn’t return it that night. I didn’t realize the size was off until I tore out the old window (yikes).

After you have confirmed the measurements. Get your drill ready, your window can now be placed into the frame. Use window shims to make the distance where the window is not touching the frame. These shims can be applied on the bottom and left and right sides of your window. Once they are in a good position where you can let your window go and it won’t fall in or out, you are ready to check the leveling using a leveler.

Level the new window

Place the leveler on the top of the bottom sash in between the window locks. Once the indication shows level. Get the drill and the screws to the screws into to the frame. I suggest going left to right. Top left and bottom right and vice versa to keep everything balanced. You don’t want to screw in an entire side and then everything is off as you go to the next side.

After you have your screws in, check for plume. Making sure you window is level and can open and close properly. Keep in mind depending on the material your window is made of you have to be mindful of temperature functions and humidity that may allow the window to close easier or not.

Insulate that new window

Here is the messy part, the DIY replacement window insulation. Now it is time to go in between the window shims or any cracks between the frame and the window and using the small nozzle on your spray foam. To do this insert the spray foam (straw) into these cracks, and pull the trigger to spray a good amount of foam. It is important to use low expanding foam because if you use a high expanding foam, there is a chance that you can spray way too much and literally move the window even though it is screwed into the frame.

Please note that spray foam gets very messy because it is very sticky and difficult to remove. I’m not saying it can’t be removed but trust me you will see what I mean if you get it on your hands or clothes. If it gets on your clothes, toss it, from my experience it doesn’t come out.

DIY replacement window insulation with spray foam

Where to put the spray foam

The spray foam goes around the perimeter of the window. Don’t worry if you spray too much. At least your window is insulated. No bugs are getting through. More importantly cold air won’t be seeping in or warm air escaping. Keep in mind that some brands offer window head expanders and sill extenders. These are designed to help fill the gap between the top and bottom of the window and frame. It is ideal to spray foam inside the head expander and behind the sill extender. This helps ensure no gaps for air to come in or heat to escape your home. Also, when you spray too much foam, don’t worry. Take a very sharp utility knife or razor blade and make a straight cut to remove the excess.

Depending on how much excess, you might decided to push it back in the cracks. To do this, use a painters tool or putty knife. Ultimately, you will cover it all up with interior trim, window molding or interior window stops. This depends on what Home Depot has in stock when you go pick up your materials.

Cleaning up the Window install

After the spray foam around the windows dries, use caulk on small cracks. Do not try to cover a .25 inch or .5 inch crack with caulk. This is where shoe stops, interior stops, or interior trim come in. They take this:

Congratulations on your first DIY replacement window install

And that should do it folks! You have successfully completed your DIY replacement window installation.

Now go enjoy your favorite cigar, glass of bourbon, IPA, coffee, or tea!

Other Helpful Resources

DIY Window Remodel  Removing an Old Window
We are all DIYers
How my wife and I became DIYers