What’s the difference between annealed and tempered glass?
Annealed vs. Tempered Glass
Annealed glass is something everyone knows but has never heard of. It is basic everyday glass and you may think of it as standard glass. Tempered glass is toughened glass and is a safety glass. It is much stronger, has more thermal tolerance, and scratches less readily. I would not put a 350-degree roasting pan on it, but it is more forgiving.
Annealed glass is certainly capable of working on interior solid top applications. The cost difference may not be significant in thinner sizes of the glass and for that reason we may recommend that you upgrade to tempered glass. Tempered glass can hold a significantly higher weight load and is generally a must for open top tables. Exterior glass tabletops must be tempered or have a different type of safety glass by code. In addition to being stronger, when tempered glass breaks, it ends up in less dangerous pebble-size pieces. Broken annealed glass ends up as large shards. An example of tempered glass you may be aware of are the door windows in your automobile.
Lastly, when ordering tempered glass, keep in mind that tempered glass comes etched with a tempering logo. When required by building codes, this logo must be visible, but most cases tabletop glass is not required to have the logo. Most customers do not like the etching and you can request to omit it by stating “no logo.”