Click here for free quotes

What’s the Difference Between Insert and Full Frame Replacement Windows?

One of the biggest questions people will ask when they’re looking at replacement windows is whether they should choose to buy full frame or insert replacement windows. However, most people looking to replace the windows in their home don’t actually understand the difference between full frame replacements and insert replacement windows.

The remainder of this window guide will focus on what full frame replacement windows are, as well as what insert replacement windows are, then compare the differences between the two.

What Are Full Frame Replacement Windows?

A full frame replacement window are indentical to new construction installation windows, in that the entire window including the window frame, window sash and window head are completely removed from the window opening and a full new unit is installed in place, with a brand new window and it’s associated components.

What Are Insert Replacement Windows?

Insert replacement windows are new replacement windows which preserve the original outer part of the window, leaving the original frame and trim of the old window intact. This essentially means that a much smaller part of the window ends up being replaced overall.

Prerequisites To Insert Replacement Windows

Using insert replacement windows is not as simple as you may think, there are a few pre-prerequisites which govern whether or not insert replacement windows will be completely suitable for your home.

The main thing which will dictate whether or not you can use a insert window over a full frame replacement will be the frame of the window itself. If your existing window frame is of wood construction then you will need to look at the overall quality and state of repair of the wood. If the wood of the frame is in any way rotten then you are going to need full frame replacement windows, rather than being able to use insert windows.

Availability Of Window Types With Insert Windows

One thing which often worries people is the availability of different window types with insert windows, in other words will you be restricted on the type of windows you can have for your home? The simple answer is that the restrictions will be minimal, there are a range of replacement window types available in the insert window style, including casement, picture, awning and single & double hung windows.

What’s The Cost Difference?

If you look at most window companies such as Marvin or Andersen for example then you will see that the replacement window cost isn’t that different between the full frame and insert replacement windows. In the mid-range window selection the cost isn’t that much to write home about.

The Major Negatives To Insert Replacement Windows

One of the major negatives to insert replacement windows which you must bear in mind before you make a decision is the overall glass loss you’ll experience. When you install an insert replacement window they are installed within the original frame, this means that you end up with a window frame within a window frame, albeit a slightly thinner frame in your original frame.

What this leads to is a certain amount of visible window low to an amount the size of the insert window frame width on either side and at the top & bottom of the window.

What you really have to ask yourself is whether the very slight price saving for insert replacement windows is worth the visible glass loss you will experience as a result. In addition to that, having a frame within a frame can look a little odd depending on the type of windows you buy.


Overall, you need to choose the windows which are right for you, don’t be tempted to go for something you’re not 100% happy with based just on cost. If it takes a little bit more time to save for new windows and you’re 100% happy then that’s probably what you need to do. It’s also important to remember that overall, the decision will also depend on the condition of your existing windows, inserts will require the existing frame and head to be in sound condition, as this video from Marvin windows explains. What did you choose for your project?

Leave a Comment

one × one =