I have 30-year-old insulated windows. A salesman told me that the seals are broken, and I am losing heat. To me the seals look fine and I speculate that broken seals should lead to condensation in the double panes. What is the best way to determine if the seals are leaking and windows need replacement?
While condensation or discoloration inside the glass usually occurs when the seals are broken, there are other factors to consider that can affect the insulation performance of your windows even if the seals are intact, such as:
- The insulating qualities of the argon gas used between layers of glass diminishes over time as it slowly leaks out at a rate of about 1% per year, which can cause a reduction in the insulating value of windows.
- Newer windows can be ordered with Low-E coatings designed for your climate that can reduce energy loss by as much as 30%-50%.
- The weather stripping around your windows may have become worn, allowing air leakage.
- Newer vinyl clad wood frames insulate better than older metal frames.
The bottom line is that replacing your windows (or the glass in them), may increase the insulation value, but you will have to weigh the savings against the cost incurred.