Wood Windows

In the parlance of window-speak, this window assembly is known as an XO configuration.

The “X” stands for “operable,” and the “O” stands for “picture” or “non-operable.”
And the window assembly is “read” or “sequenced” from left to right (the same as reading this sentence). And this is to be applied as viewed from the exterior. This is how window-folks are able determine which sash, and which kind of sash we are speaking of when communicating with one another.

Thus, in this case, the window-sash on the right, as viewed from the exterior is a non-operable (O) sash. As you can see, the wood sash is so water-damaged that the extruded aluminum-cladding is peeling off the bottom-rail of the sash.

The evidence is just as obvious when viewed from the interior. If you enlarge the photo, you may be able to see the damage a little better.

The wood in the bottom-rail and the stiles is simply disintegrating all the way through.

Unlike so many brands of wood windows that we repair, the Pella picture sash are unique in how they are installed into the jamb assembly.

The manufacturer really provides no means by which these sash can be easily removed for repair. If you enlarge the photo, you may be able to make out one of the many screws they use to hole the sash in place.

A generous assessment of why they do this might be for reasons of structural integrity. But it makes it challenging to work on these windows in the field. And expensive to repair. So the water-damaged components are painstakingly removed and the new material installed with the sash left in place.

After which the cladding is re-adhered to the sash (previous photo) with bracing material installed to hold the aluminum-cladding in place until the adhesive has opportunity to cure to some degree. And then all the seams are carefully masked for a professional application of caulking.

The finished product.