The Future of Window Replacement

Jim Snyder
October 11, 2013
COLUMN : From the Field | Methods & Techniques

In my last column I asked, “Will the replacement industry, as it is today, work for tomorrow?” I wasn’t referring to energy and performance standards; clearly, those will continue to advance. Instead, I was referring to the actual replacement process itself. Replacement, as we know it, consists of either installing a replacement product or exchanging a full frame. Both of these options will face new challenges as fenestration products evolve.

Fenestration replacement is contingent on three primary elements: the existing in-place product, the building structure and the original installation technique. Each of these elements is changing as a result of new construction products and practices. The replacement industry will take on a whole new look as new products―and homes―emerge.

I ask for a bit of latitude in this article, since I can’t capture all possible replacement scenarios. Allow me to generalize with two points.

Traditional Replacement Products are Becoming Less Applicable

All current replacement products (inserts, sash kits and flush fin) have one thing in common: they all reuse the existing frame. This makes sense in many ways: It saves time, is cost efficient and requires less skill than a full frame exchange. And, it doesn’t disturb the existing wall interface.

Each of these replacement products is designed for—though not entirely limited to—a specific application. For example, the insert mounts in the 3 3/8-inch-deep sash pocket of an existing all-wood double hung, whereas the flush fin mounts to an existing aluminum slider frame.

But what is the replacement product for, say, an existing double hung made of clad-wood? Or vinyl? Or fiberglass? These more complex nail fin products don’t have the traditional sash pocket, nor do they have removable stops for pocket access. Traditional replacement products fit a large market, but they can’t accommodate all scenarios.

Full Frame Replacement is Becoming Less Practical

Even full frame replacement is becoming much more restricted due to the limitations posed by existing structures and the manner in which original units were installed.

When completing a full frame replacement, it is critical to “do no harm” to the wall interface, especially in a membrane/drainage type structure. This is more easily accomplished when replacing an older all-wood unit secured by the exterior casing against sheathing of an older structure with minimal or no weather-resistant barrier. There simply isn’t much to harm.

Compare that to removing a nail fin product installed according to today’s installation standards. Interlaced with flexible flashing and the weather-resistant barrier, the nail fin is completely concealed by the exterior veneer―(perhaps brick)―with no exterior casing, in many cases. While the old unit can be removed―(shall I say “torn out?”)―from its perimeter, damaging the wall interface is unavoidable. Properly securing, flashing and sealing the new unit with the WRB is impossible, short of removing some of the exterior veneer.

Looking Ahead

So if current replacement products are becoming less applicable, and full frame replacement is becoming more impractical, what could “replacement” look like in the next few decades?

OK. I’ll speculate.

Because we will be dealing with more brand-specific extrusion and pultrusion shapes rather than generic all-wood profiles, universal replacement products will fade away. I’d venture a guess that brand-specific upgrade components will become the new version of replacement: a sash kit kind of enhancement for double hungs, and also for casements, along with new hardware.

Full frame replacements will become less frequent thanks to more norot frames. The exception would be due to a damaged frame, or improper initial installation as a part of the wall interface. In that case, there would be no easy fix, and the project might demand an entire exterior veneer/wall interface upgrade.

What is your best guess as to what the future of window replacement will look like?

Jim Snyder has worked in the residential new construction, remodeling and fenestration industries for more than two decades. His website features a regular blog on installation topics, and he welcomes questions and feedback from readers at