How to Replace an Old Window

Tips on Replacing an Old Aluminum Window with a New Vinyl Window

By Mark J. Donovan

  Question: Mark, I have a question regarding aluminum frame windows. My home is about 30 years old, and I want to replace the old windows with new vinyl windows.

The window frame has a flange nailed on the outside and the wood siding is on top of it. There is no wood trim around the window.

How do I remove the old aluminum window frame and how do I install the new window?

Answer: D.C. Years ago I had a similar problem when I was replacing old windows in my home. The siding was wood and it butted right up against the old windows.

What I wound up doing was cutting back the siding about 3 inches around the top and sides of the old windows to expose the window flanges. I used a skill saw to make the cuts after first measuring and using a straight edge and pencil to mark my lines.

I then went inside the house and removed the interior wood trim pieces from each of the old windows.

Once I cut away the strips of siding and removed the interior trim pieces, I was able to use a flatbar and hammer to remove the nails that held the old window flanges in place. I was then able to slide the old windows out of their window frame openings.

After removing each old window, I slid a new vinyl window into its place, and made sure it was centered and level in the window opening. I then nailed the new window flanges to the exposed house sheathing.

To complete the window replacement, I then installed 3 inch wide, fully primed, wood trim pieces above and to the sides of the new vinyl window.

To make sure no water seeped in between the upper trim piece and side trim pieces I installed small pieces of zip metal flashing on the top edges of the two side pieces of trim.

I also installed zip metal flashing over the top edge of the upper trim piece.

Finally, I caulked around the new vinyl window frames and where the house siding met the new exterior window trim boards.

How to Install a Window Ebook

If you need more help on choosing the right window replacement for your home, contact one of our pre-screened window installation contractors. They can help you select the replacement windows that are right for your home and budget, and perform the installation.

For more information on Installing Replacement Windows and Interior Window Trim

  • See the Installing a New Window Ebook from  The Installing a New Window Ebook provides easy to understand, step-by-step instructions, on how to remove an old window and install a new one. Pictures are included for every key step in the process.

Installing a New Window Ebook

  • See the Installing Interior Window Trim Ebook from  The Installing Interior Window Trim Ebook provides easy to understand, step-by-step instructions, on how to install interior window trim around a window. Pictures are included for every key step in the process.

Installing Window Trim eBook

Related Information on How to Replace Old Windows and Installing Window Trim

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