How Does Sunlight Affect Stained Glass?

Whether you already have a stained glass window in your home or you’re thinking about investing in one, you need to understand the effects on sunlight on stained glass so you can protect your investment. While sunlight enhances the beauty of a stained glass window, the UV rays can also cause some significant damage. Here’s a brief guide to how sunlight affects stained glass, as well as what you can do to protect your window.

Sunlight negatively affects certain types of glass

The quality of glass used to create stained glass works of art is important, and so is the technique employed by the artist. Low-quality glass and certain methods that don’t involve completely baking the glass can result in a piece that doesn’t hold up as well to sunlight. Not only can UV light cause the colors to fade over time, it can also damage the glazing, laminating and even any decorative paintwork on the window’s surface. It pays to invest in high-quality glass and effective techniques.

High-temperature baking results in greater UV resistance

Baking stained glass at high temperatures bakes in the color, making it much more resistant to UV light. When a stained glass piece is baked at temperatures of 350 degrees or more, it shouldn’t fade or need restoration from light damage for 75 years or longer. The high temperatures blend the sand molecules in the glass with special minerals that produce long-lasting colors. As the glass cools, the structure and color are locked in, and they can only be changed when heated to the same high temperatures involved in its creation.

Sunlight directly affects humidity levels

It’s not just the light from the sun’s rays that damage a stained glass window, but also the heat it generates. The warm air around your windows can hold a large amount of water vapor. Whenever the temperature and humidity inside your building are lower than outdoor conditions, condensation can settle on the glass and cause some damaging effects. Not only does condensation deteriorate the color of the glass, but it also degenerates the material itself. Too much exposure to humidity can quickly damage a stained glass window, which is why you should invest in a protective covering with appropriate venting.

Take protective measures to guard stained glass from sunlight

Now that you understand how sunlight affects stained glass, there are protective measures you should take to preserve stained glass windows and other features that are directly exposed to the sun. You could invest in a covering to create a barrier between the window and the elements, including sunlight, moisture, pollution and pests. Always pair a covering with a vent and frame to promote airflow and reduce the chance for humidity to damage your window.

Interested in learning more about the effects of sunlight on stained glass? Smiths’ Stained Glass can help protect your stained glass windows from fading and deteriorating over time due to the elements. Reach out today to discover how to preserve the beauty of your windows for years to come.