
Replacement Window Installation Options
When it comes to home repair jobs, few choices can produce a more dramatic impression than replacing your home windows. But while many other improvements can be completed with a little work and a good blueprint, replacing a home window demands substantial work and a good deal of technical knowledge.
As a result, replacing your windows is no easy job. You’ll want to understand what type of window is necessary, the specific plans required for replacing the window based on the size of the opening, and what materials it will take to make the proper fit for your replacement window.
There are 2 main options for replacing windows: full frame (nail fin) replacement and block frame (retrofit). There are advantages to both. Read below to see which one is the best option for your home.

Full Frame Replacement
Using a full frame replacement window, as the name infers, typically requires replacing the existing window frame, sashes and screen. This can usually be done with a utility knife, screwdrivers, pry bar, hammer, putty knife and circular saw, depending on your current window. We generally use windows with a nail fin attached for this type of install.
Nail fin windows are frequently seen in new construction projects, or any remodel where the walls will be exposed to the frame (studs). These windows feature a thin piece that extends from the window itself that follows around the outer edges of the window frame. When installing the window to a new frame, this nail fin attaches the window directly to the house’s studs and is unseen between the interior and exterior of your home.
Adding a nail fin window can be hard work and may require the addition of a new window frame or removal of siding so the installer can attach the nail fin to the studs. If you are wishing to install a nail fin window to a present wall in a section of the house where a stone or brick exterior would also have to be replaced, the job might not be worth the time demanded.
That said, it is the best way to get the largest window and provide the best water intrusion protection.
Block-frame Replacement
Replacement block frame (also known as pocket replacement) windows are slightly different than full-frame replacement windows and are built to fit inside an existing window frame. While the existing window sashes and exterior stops of the window should be taken out for the new window to be installed, pocket replacements allow homeowners to keep the original frame, trim, siding and casing.
Just as with full-frame window replacement, the wall exterior surrounding the window opening will play a role in how the pocket replacement process works, this time with fewer steps. Unlike full-frame replacement window removal, the existing window is cut out, typically with a reciprocating saw (Sawzall).
The replacement window can be placed into the opening and existing frame and attached to the frame with screws. Foam insulation is used in the space between the window and frame. Caulking prevents water intrusion and then trim is installed to complete the look of the window.
Often, some minor touch ups on the interior drywall, paint, etc. and possibly the exterior siding, stucco, etc. will need to be made. In general, block frame replacement is much simpler and less invasive than full frame replacement and is the more cost-effective installation option.

Which option is right for you?
There are pros and cons to each.
If your budget allows, we usually recommend opting for the full frame replacement. It provides the largest window for the opening and gives the best protection against water intrusion, but it is much more involved in labor and materials, so the price is generally higher.
For the block frame option, some maintenance will be required with the caulking every few years and, as mentioned, the pocket windows have to be slightly smaller. If price is the major concern, the cost savings of the block frame can be significant.
All of our favorite window manufacturers, Pella, Andersen, and Sierra Pacific, offer both nail fin and block frame replacement windows, so you can get a high-quality window with either installation option!