Background

We were not happy with the appearance of the four new double hung replacement windows in our kitchen and two bathrooms. For us, there were two main problems:

We decided that the other 12 double hung windows would not be replaced in this way. I looked at so-called “New Construction” windows and was not very satisfied either. For one thing, all of those that I looked at would have required siding alteration. Worse still, we didn’t like the appearance of windows when the plane of the window glass is moved outward and close to the plane of the house facade. 

Solution

We used replacement windows but we installed them in an unconventional way – we removed the old jambs so as to obtain more glass area.

Construction

Prepping involved pulling off the outside casings, cutting loose the jambs and pulling out the old window. The outside casings had been nailed to the old jambs and we couldn’t nail to the new vinyl jambs so we had to put nailing strips on the jack studs.

After fastening the new window, the cavities were foamed and the outside casings were nailed back in place. 

The gain in glass area and appearance by unconventional installation of replacement windows is readily apparent on the photos. To put it in numbers, our installation method increased the glass width by 1–¾ inches when compared to conventional replacement window installation. 

Had we been willing to undertake some clapboard and outside casing changes we could have gained another inch in glass width on each window.

Conclusion and Comments

While planning the job, I shopped for windows at Lowes, Home Depot, several lumberyards and some big name window manufacturers as well. Every one recommended using replacement windows, but no one ever mentioned the uninsulated counterweight cavities that might be hiding behind the old jambs. (Could it be that people still think still air is the best insulation?)

If you’re going to upgrade with replacement windows, you might want to plan on pulling off the outside casings and taking a look. Actually, the same advice applies if you’ve already upgraded with replacement windows – especially if you still have those cold drafts.