Restoring Sash Windows

Restoring Sash Windows
Sad state of neglect.
Things can be made to look better with a little elbow grease. Still needing touchups and final go-overs, this older sash will eventually look 100%.
Damage such as this doesn't happen overnight. It sneaks up, like needing a haircut, until one day people start avoiding you as if you were suddenly caught being socially thoughtless in your underarm protection ritual.
Moisture and/ or standing water will give any paint film a run for it's money. Rain water exposure from outside has seeped in and contributed to an interior moisture build-up with this eventual damage.
Moisture may not be the main cause of paint failure. Sometimes the substrate itself is the culprit. Many and multiple coats of a paint film eventually react with one another, setting up stresses which cause peeling and cracking. You can see something similar with ice. The colder it gets, the thicker the ice, and the higher are the pressure ridges on a lake. This flake reveals wood fibers on its inside, which means of course, that this flake goes back to the neolithic era, right down to the original wood. Surprisingly, the wood proves to be quite sound -- not the least bit petrified or coal-like in nature.
Prepped up and ready for priming. Older paints are likely to contain some nasties. Use protection and common sense when generating dust (as in sanding). Use protection and common sense in other activities too -- like ear protection when the neighbours play rap music. Or use common sense and hire me for your painting jobs so that you can go off to your bridge game. I like it when you do that.
Good as new now for many more years. While you have the window removed, paint the exterior top strip. Keep your refurbished windows opened at a chosen height by using a finishing nail. Clean-up the glass the professional way.