When homeowners consider installing transom windows, questions often arise about specific window types and their safety features. One such query is: do transom windows need to be tempered? The answer isn’t as straightforward as a simple yes or no, so let’s dive into the details.
Transom windows, typically found above doors or other windows, enhance homes’ aesthetics and natural light. However, their placement and design raise safety concerns, especially with young children or pets in the household. This leads us to explore the need for tempered glass in transom windows.
Understanding Tempered Glass
Tempered glass, also known as toughened glass, is strengthened through a heating and rapid cooling process. This procedure increases its strength and safety by making it four to five times more resistant to breakage compared to annealed glass. In case it does break, it shatters into small, relatively harmless pieces.
Building codes and safety standards often regulate where tempered glass is required. Let’s explore when transom windows necessitate tempered glass.
Falling Hazards: Mezzanines and Multi-Level Homes
Transom windows placed high up on a wall or above a staircase in multi-level homes or lofts with mezzanines pose a falling hazard. If a person leans on them, they could break, leading to serious injuries. In such cases, building codes often mandate the use of tempered glass to minimize risks.
For instance, the International Residential Code (IRC) R308.2.1 states that glass in hazardous locations, such as over stairs or near walking surfaces more than 36 inches above the floor, must be tempered or laminated.
Window Size and Placement
Tempered glass is also recommended for transom windows larger than 24 inches by 36 inches or those closer than 18 inches to the floor. The larger the window or the closer it is to the ground, the higher the likelihood of accidental impact, making tempered glass crucial for safety.
Installing tempered glass in smaller windows or those higher above the floor isn’t typically required but can still enhance safety. It’s always a good idea to prioritize safety, even if not mandatorily required by building codes.
Weight vs. Strength: Laminated Glass for Transoms
Laminated glass is another safer alternative, often used in car windshields. It comprises two panes of glass bonded together with an interlayer. This structure increases impact resistance and retains glass fragments even if broken, offering added safety.
Laminated glass can be tempered for enhanced safety, but it’s worth noting that tempered glass is generally stronger than laminated glass. However, for transoms typically bearing minimal weight and not subject to heavy loads, laminated glass can suffice in many cases.
Soundproofing and Energy Efficiency
While not directly related to safety, homeowners should also consider the benefits of tempered glass. Tempering can improve a window’s energy efficiency by reducing UV penetration, which helps protect furniture and flooring from sun damage. Moreover, thicker tempered glass can enhance soundproofing, reducing outside noise.
Laminated glass also offers soundproofing benefits, and some varieties can even block 95% of UV rays, making it a suitable option for transom windows in high-traffic areas or above valuable furnishings.
In conclusion, while not always mandated by building codes, tempered glass is generally recommended for transom windows to enhance safety. Considering window size, placement, and potential hazards, homeowners should prioritize safety and consult local building codes to make informed decisions about their window installations.
