This course is part of the Custom Home Academy

Standards

Glass doors and windows can generally be evaluated by most of the same third-party independent testing standards. These include comprehensive testing by the National Fenestration Rating Council (NFRC) which identifies the total energy performance of tested units for heat transfer (U-factor), solar heat gain, visible light transmission, air infiltration, and condensation resistance. It also includes the Fenestration and Glazing Industry Alliance (FGIA), which is a recent collaboration of the American Architectural Manufacturers Association (AAMA) and the Insulating Glass Manufacturers Alliance (IGMA). The FGIA now provides standard testing and standards for all types of windows and doors. Finally, there is also ASTM International, which has developed numerous tests for different types of glass, glazing systems, and window and door products. All of these are relevant performance standards for exterior glass doors of all types, just as they are to windows and similar fenestration.

Case Study: Beachaus Modern

Photo courtesy of Marvin

This residential new-build project in White Rock, British Columbia, uses a big-glass design that makes it 100% naturally lit by daylight while still reducing heat loss and heat gain through high-performance windows.

Inspired by beach houses that line the California coast, this residential new-build project in White Rock, British Columbia, was boldly modern in its design approach. It was also ambitious in its goals to achieve LEED status. It would be a small-footprint, high-efficiency home that was 100% naturally lit by daylight, which meant that the glazing package was a critical part of the project, both aesthetically and performance-wise.

The architectural design featured floor-to-ceiling glazing in conjunction with the 12-foot ceilings to provide the illusion of space. The large number of south-facing openings required finding an innovative solution to reduce heat loss and heat gain to qualify for LEED Platinum status. The designers opted for casement and awning windows, as well as sliding patio doors, that were all made with energy-efficient, double-pane glass with Low-E coating, which optimized the home to effectively minimize heat loss and heat gain.

The windows sport sleek, ebony exteriors that give the modern home a clean, minimalist look. The windows and doors were chosen for their heat resistance, noncorrosive qualities, and low conductivity for energy efficiency.

And as ENERGY STAR certified windows and doors, the owners can potentially cut heating and cooling costs by 12%.

HEALTHFUL HOMES BY DESIGN

"For years, we’ve been following emerging ways of living in the home and uncovered a clear desire for more access to natural light, air, and views. The pandemic heightened homeowner awareness of these desires and fast-tracked renovations and remodeling to realize these benefits. Today we’re seeing homeowners strive to strike a balance between flexible multi-purpose spaces and dedicated areas for respite while integrating the outdoors and leveraging their home in pursuit of better living."
-Christine Marvin, CMXO Marvin Windows and Doors

In a 2013 University of Colorado study published in The Journal of Sleep, participants spent a week camping in the Rocky Mountains without access to artificial light. During the first two days of the camping trip, they were not allowed to use flashlights or electronic devices, and they were exposed only to natural light during the day and darkness at night. For the next five days, the participants were allowed to use flashlights and electronic devices, but they were still exposed only to natural light during the day and darkness at night.

The results of the study showed that exposure to natural light during the day helped to regulate the participants' circadian rhythms. The researchers found that the participants' melatonin levels, which are a marker of the body's circadian rhythm, were synchronized with the natural light-dark cycle. And that synchronization is what helps promote healthy sleep patterns and wakefulness during the day.

The study also found that exposure to natural light during the day led to an increase in physical activity and a decrease in the amount of time spent in sedentary activities. This study, among others, has helped architects and designers understand the importance of and consider approaches to designing homes and buildings that allow for natural light to enter the indoor environment.

With an emphasis on large expanses of glass, big-glass designs can have a significant impact on the health and well-being of building occupants. In a University of Illinois study, natural light improved the mood and physical activity of office workers—evidence that can easily translate to remote workers or occupants with in-home offices. Studies with school children and with elderly people in nursing homes have also shown the benefits of natural light, in both cognitive performance, mood, and over health.

Big-glass designs also provide a connection to the outdoors, which can reduce stress levels and increase feelings of well-being. Views of nature have been shown to have a positive effect on mental health. In addition, large operable glass windows and doors provide a literal connection to the outdoors—encouraging homeowners to step outside and utilize outdoor areas for serene relaxation, entertaining guests, and other activities.

Natural ventilation from operable windows can have several positive effects on occupant health and well-being. It can help improve indoor air quality by bringing in fresh air from the outdoors and flushing out stale indoor air. This can reduce levels of indoor air pollutants, such as volatile organic compounds (VOCs) and carbon dioxide, which can cause respiratory problems and other health issues. It can help regulate indoor temperature and humidity levels, creating a more comfortable indoor environment, and ultimately leading to a reduction in the need for mechanical cooling and heating, which can save energy and reduce costs.

The regulation of indoor temperature and air quality leads to another benefit: It can promote better sleep quality. Studies have shown that, just like with natural light, exposure to fresh air and lower indoor temperatures can lead to deeper, more restful sleep. During the day, natural airflow can promote relaxation and reduce feelings of anxiety and stress, which tends to have a ripple effect of benefits for occupants.

As mentioned earlier, high-performance big-glass designs can improve thermal comfort by allowing for natural daylighting and solar heat gain, which can help reduce the need for artificial lighting and heating. Glazed facades can help reduce outdoor noise levels, providing a more peaceful indoor environment. Acoustic glazing can also be used to further reduce noise levels and create a more comfortable indoor environment. Architects should consider these factors when designing with large glass panels and mulling designs to ensure they meet the needs of occupants. When designed well, a home with enhanced views, natural ventilation, and natural light can greatly impact the lives of its occupants for the better.

Big-glass design doesn’t just affect the well-being of occupants, it influences the outside environment. Designers can have a positive impact on the aesthetics of a home and the surrounding area. Homes with large glass facades can add visual interest to both urban and rural landscapes and can create a sense of openness and transparency. In addition, when natural light enters a building and the surrounding area, it can improve the mood and well-being of people who view the building, as well as the occupants.

Erika Fredrickson is a writer/editor focusing on technology, environment, and history. She frequently contributes to continuing education courses and publications through Confluence Communications.