How to Tell If Your Window Seals Are Failing
Window seal failure is easy to miss at first, because the window usually still opens, locks, and keeps the weather out. When that barrier breaks down, moisture gets inside the glass unit and the window loses part of the insulation it was built to provide. If the moisture is trapped inside the glass layers, the seal has likely failed and the insulating gas may already be gone. What is not normal is condensation that sits inside the insulated glass itself, or water d