How Windows and Doors Can Make a House Feel Good

Designing a custom home that promotes occupant well-being includes specification of windows and doors that provide natural light, views of the outdoors, natural ventilation, and comfort

By Kathy Price-Robinson

The designer of a custom home asks many questions: How will the design look from the street? How contemporary or traditional will it be? Will it stand out in the neighborhood or fit in? How will it be laid out on the inside? How many rooms? How energy efficient will it be? How sustainable?

But arguably, the most important questions are:

• How will the occupants feel inside the home?
• Will the house help them thrive or just survive?

In both questions, windows and doors are a significant part of the solution, and the knowledgeable designer will consider the wellness of the custom home’s occupants in all design decisions and specifications.

Humankind’s Connection to Nature

Let’s consider how we humans have lived for the vast majority of our time on the planet. Many scholars put the first homo sapiens (also known as anatomically modern humans, or AMHs) as emerging about 350,000 years ago.

But behavioral modernity, which includes the development of language, early forms of religion, and figurative art, is thought to have arisen more than 40,000 years ago. This distinguishes the beginning of the Upper Paleolithic, or Later Stone Age.¹

Early humans were gatherers and hunters, nomadic, and inextricably immersed into the natural world of plants, animals, water, sunlight. There was essentially no existence separate from nature.

Even when agriculture was practiced and permanent shelters were built, much of human time from sunup to sundown was spent outside, with farmers and shepherds intimately connected to nature and its seasons.

Fast forward to today, where humans spend more than 90 percent of our time indoors, effectively shut off and alienated from nature.³

The move into indoor life is but a blip on the scale. Humans emerged 40,000 years ago, and modern humans have lived and worked mostly indoors with artificial heating and cooling and ventilation for less than 200 years.

Day-to-day life has changed drastically for us, but organisms do not evolve that quickly. It’s no wonder some say we are a “dis-eased” civilization, with rising attention disorders, obesity, depression, and other maladies. Some research suggests that our separation from nature could be partially to blame.

The Concept of Biophilia

The term biophilia comes from the Greek roots meaning love of nature. It was coined by the social psychologist Erich Fromm. In the 1980s, an American biologist named Edward O. Wilson brought the term biophilia into widespread use with his writings about human need to be in contact with nature. He described biophilia as “the innately emotional affiliation of human beings to other living organisms.”³

Nature provides a great source of inspiration for an architect or designer. As Wilson said, the natural world “exceeds in complexity and beauty anything else humanity is ever likely to encounter.”

We are not likely as a species to return to gathering and hunting and shepherding. Our reliance on indoor environments will continue. But the designer or architect can create indoor spaces that increase our connection to nature, provide respite and solace, and thereby contribute to occupants’ overall well-being. Windows and doors play a critical role in terms of bringing natural light, views of nature, natural ventilation, and operational comfort into a custom home.

The Importance of Natural Light for Human Well-Being

Providing natural light for occupants goes way beyond saving on the energy used by artificial lighting. Natural light contributes to the health and vitality of the home’s occupants. Strategically placed windows and doors that bring natural light into an environment can provide health and happiness benefits to generations of occupants.

Natural Light Contributes to Natural Sleep/Wake Cycles

Throughout history on the planet, natural light tells organisms on a visceral level when it’s time to awaken and engage in the world, and when it’s time to slow down and retire. Natural light stimulates hormones that cause the body to engage. The lack of natural light stimulates hormones that cause the body to relax and retreat.

The body’s response to daylight is one area where the power of biophilia becomes evident. Light exposure plays an important role in a healthy sleep/wake cycle, and daylight affects our inherent circadian rhythms: physical, mental, and behavioral changes that follow a daily cycle. These rhythms are primarily regulated by light and darkness in one’s environment, as well as the tone of light, such as bluish light in the morning and warmer light in the evening, and are recognized by a third type of receptor in our eyes.⁴ The sun as a light source connects to our internal clocks, telling us when to wake and sleep.⁵

Dr. Mithu Storoni, physician, researcher, and author of Stress-Proof, states, “The brighter your daylight exposure, the more melatonin you produce at night.”⁶ Melatonin is a type of hormone that is produced by the pineal gland in the brain during darkness at night. It is sometimes called the sleep hormone. So the amount of daylight exposure we get is critical for maintaining a normal rhythm of sleep and wakefulness.

How Natural Light Affects Mood

Many people rely on many hours a day of natural light to feel their best. When natural light is not available, the mood suffers. When days of winter have fewer hours of daylight, some people sink into such a deep lowered mood that it is clinically named seasonal affective disorder, or SAD. Providing abundant windows in a home to capture maximum natural light helps the occupants feel and function better.

When a home’s design embraces and enhances the benefits of natural sunlight through deliberate choices that strengthen our connection to the outdoors, those much-desired feelings of well-being are a natural result.

Statistics Prove Health Benefits of Natural Light

Health statistics are clear that natural light boosts well-being. Consider these:

• People’s problem solving is up to 7 percent faster when they have views to vegetation.⁷
• Children achieve up to 26 percent improvement in test scores when they have access to natural daylight.⁸
• There is up to 41 percent reduction in length of hospital stays in bright, sunlit rooms.⁹
• Evidence has shown that natural daylighting can improve nursing performance, leading to a decrease in errors.¹⁰

Consider the economics of health care. In 2010, the United States spent $40 billion on health-care construction. As reported in “The Economics of Biophilia” by respected consulting firm Terrapin Bright Green, more than 50 studies have been published that “associate biophilic elements as primary influences for faster recovery rates for patients, decreased dependency on medication, reduced staff and family stress, and improved emotional wellness as a result of natural daylighting and views to nature.”¹¹

It can be assumed that the healing nature of natural views carries over to homes, where occupants healing from an injury or illness will experience a faster recovery time when the home’s design provides views of nature.

Natural Light and Universal Design

The ability to see well plays a part in occupants feeling comfortable and being safe in a home. Studies show that when eyesight fails due to age, illness, or injury, satisfaction with living diminishes. Natural light makes it easier to read or work at a sewing machine, for instance. Artificial lighting manufacturers have worked hard to replicate the waves of natural light in their products, but it could be assumed that natural light itself is better.

Lack of Natural Light and the Sick Building Syndrome

Conversely, research has shown that a lack of exposure to light can make us sick, and some countries have already begun addressing their citizens’ right to light. In Japan, skyscrapers and intense urban density led to the concept of “nissho-ken,” which translates to “a right to sunlight.” After a series of legal actions, more than 300 Japanese cities adopted “sunshine hour codes,” specifying penalties that developers must pay for casting shadows.¹²

The Japanese were early to realize the impact of sunlight on health and happiness, crucial when you consider that we spend up to 97 percent of our time indoors.¹³ All the more reason to bring light into the home since we may not get outside much to experience it.

Design Ideas to Provide Natural Light for Occupants

• Add clerestory windows for natural light, privacy, and to retain wall space.
• For contemporary designs, narrow window frames allow in more light.
• French interior doors can stream natural light from room to room.
• Window boxes, which are essentially nooks where all sides are windows, provide a seating area where one is surrounded by the healthful effects of natural light.

THE IMPORTANCE OF VIEWS TO THE HEALTH AND WELL-BEING OF BUILDING OCCUPANTS

A tenet of biophilic design is to give clients both refuge and prospect. Refuge is the home itself, providing a safe and nurturing place for the occupants to feel secure and protected. At the same time, prospect is needed. That is the ability to look out and see in the distance. Imagine ancient human cave dwellers, positioning their habitats on a hillside to benefit from the safety of the hill or mountain behind them and the ability to see who is approaching in the distance. Designers can provide both refuge and prospect to their clients with strategically placed windows and doors that provide those views.

Windows and fenestrated doors provide a sense of place. The views outside inform occupants about where they are in the world, what plants and animals live there, and the movement of the seasons. The need for this type of information lies deep within based on our 40,000 years of collective memory.

Views Help Satisfy the Human Need to Connect with Nature

Gazing outside inspires a direct connection to the healthy, natural state that people experienced when they spent most of their time outdoors.

“The feeling of being in nature stays with you, even while inside looking at trees, a garden, or patio,” says Manny Gonzalez, FAIA, LEED AP, principal and board of directors at KTGY, a Los Angeles-based architecture firm.¹⁴

“If you do a good job as an architect, the resident won’t even know that they’re experiencing biophilic design,” Gonzalez adds. “They don’t even think about it—it just feels good.”¹⁵

Design Ideas to Provide Views for Occupants

• Scenic sliding, multi-panel doors bring the outdoors in, connecting the inside space with the environment.
• Bi-fold doors also open the inside to the outside with a single swinging active access panel door that allows for convenient everyday use.
• Picture windows in unexpected places, such as in a stairwell or along a perimeter hallway, give occupants more opportunity to connect with the outdoors.
• Contemporary/narrow window frames allow for better views.
• Minimalist hardware on windows and doors can provide least distraction from the views.
• French doors provide access to views and are available in sliding, in-swing, and out-swing options.

The Importance of Natural Ventilation for Health and Well-being

Biophilic design is often focused on the sight of nature and the changing seasons. But biophilic design involves all the senses. When you are immersed in nature, what do you feel? What do you smell? What do you hear? What do you breathe? Natural ventilation via operable windows and doors in a custom home brings in these healthful sensory factors, as weather permits, for the benefit of the occupants.

Biophilic Design Health Statistics

Scientific study has proven, without any question, the benefits that natural air, sounds, and smells bring to modern humans. Here are a few samples:

• Studies report up to 23 percent reduction in headache symptoms when subjects were provided outside air.¹⁶
• There have been up to 69 percent reduction in asthma symptoms in students when schools upgraded to displacement ventilation to increase fresh air.¹⁷
• Listening to nature sounds causes relaxation in people who begin in a state of stress.¹⁸
• A virtual-reality forest including sound was found to improve stress recovery more than the same forest without sound.¹⁹
• In an experiment in a fragrant garden, natural odors derived from blooming plants increased calmness, alertness, and mood.²⁰

Design Ideas to Provide Natural Ventilation for Occupants

• Casement-style windows are hinged on the side and can either swing inward or outward, depending on the desired style.
• A venting picture window is a unique way to bring natural light into a room or highlight a beautifully expansive and unobstructed outdoor view. Thanks to the design, it can also be a source of fresh air. A venting picture window is designed with a hidden screen system, allowing it to open evenly on all sides for passive air exchange. Limited sash travel can enhance security by reducing the appearance of an open window from the exterior.
• Push-out casement windows are an alternative to crank-out-style casement and awning windows. Quality push-out casements include a multi-point locking system that makes them easy to operate. This type of window offers the advantages of modern technology wrapped up in the traditional look of a push-out window.
• Contemporary casement windows feature a flush exterior frame and sash as well as a narrow frame, suitable for projects looking to achieve a contemporary design. They are generally available in large sizes for massive views with streamlined sightlines.
• An inswing casement window complements classic architectural styles. Inswing casements are particularly desirable where an outswing window would interfere with a patio, deck, or outdoor walkway. An inswing casement can open to 180 degrees so it is completely out of the way when open. A variation is a French inswing casement for a sweeping, wide view when open, with no center post to spoil the scenery.

The Importance of Passive Comfort for Occupants

Of course, you want the occupants of the home you design to be comfortable—but you don’t want them to have to work hard for that comfort. They should not need to remember settings and learn complicated systems to be comfortable. The comfort your clients need should come easily and automatically in response to the laws of nature and the features you designed and included to take advantage of those laws of nature.

The passively achieved areas of comfort that your clients want, need, and deserve include thermal, acoustical, and operational comfort. We’ll examine each one separately.

Thermal Comfort

Thermal comfort means in part that there are no hot or cold spots and all areas of the custom home are an equal, comfortable temperature. While high-tech, quality windows and doors contribute to energy savings since heated or cooled air is not leaking out, they also by the same efficiency add to thermal comfort. Comfort (and energy efficiency) is achieved through the use of various window technologies. Low-e coatings, frame materials, glazing types, spacers, gas fill, and weather stripping all contribute to windows that resist the flow of heated or cooled air from inside to outside.

Specific factors to consider include:

Insulating glass (IG), where two or more glass panes separate by an air space to reduce thermal transfer.

• Low-e glass, which stands for low emissivity. Microscopically thin, transparent metal or metallic oxide layers deposited on a glass surface suppress radiative heat flow and reflect interior infrared energy (heat) back to the inside, reducing heat loss through the glass. Various low-e coating options can manipulate heat gain to match different climate needs.
• Gas fills of argon or krypton mixes reduce conductive and convective heat transfers in IG air-spaces and improve thermal performance.
• U-factor measures the rate of heat loss and is usually referred to in terms of energy savings. But it also measures thermal comfort. Different custom-home clients will desire different levels of efficiency, but a “good” U-factor for a window is less than 0.30.
• In contrast, the solar heat gain coefficient (SHGC) rating measures solar radiation, or how much solar heat is admitted through a window. Low SHGC numbers are best for southern climates where there’s intense sun exposure, whereas higher SHGC values make the most sense for regions with cold winters. In both cases, proper SHGC ratings will equal thermal comfort.
• Frame materials contribute to thermal comfort. For example, fiberglass windows, whether they’re made completely of fiberglass or clad, have superior weatherization and insulation properties when compared to alternative materials. This makes them ideally suited for homes built in harsh locations and in homes where both comfort and energy efficiency are important. With its very low conductivity, fiberglass is also the best insulator among window-frame materials. And it shrinks and expands at the same rate as glass, making its air-seals as durable as the rest of the unit.

Acoustic Comfort

As we contemplate the 40,000-year history of humans, we can imagine the sounds we lived with for those millennia—wind, rain, animals, quiet. The cacophony of city or even rural life—automobiles, buses, delivery trucks, airplanes, garbage trucks, and so much more—is far from our shared history.

To ensure a quiet interior environment for occupants, consider the sound transmission class (STC) ratings for the home’s windows and doors. This is a rating for all common noises, such as television, music, and speech. The STC rating system has been around for decades, and the table below will help to compare STC-rated units with one another.

Although STC ratings above the mid-30s are achievable, they may compromise the aesthetics of the window through exterior combinations, interior sash panels, or creating a bulkier sash. This is often done to achieve rates of STC values that may be unnecessary for residential homes to obtain comfortable noise levels inside. It is usually not necessary to compromise aesthetics for STC. Proper specification and installation of windows with values in the high 20s will provide the acoustical comfort needed. Discussions with the window manufacturer will be useful.

Operation Comfort

While the practice of biophilic design draws inspiration from the natural world and the experiences of early humans, that is not to say that difficulty in day-to-day living is valued. Of the many benefits of modern life, being comfortable is highly valued. In terms of windows and doors, ease of use brings comfort to a home’s occupants.

“We’ve found through observation and interviews that whether they’re younger, older, able-bodied or not, every person wants a product that’s easy and effortless to operate,” says Brenda Brunk, senior product manager at Marvin Windows and Doors.

Here are examples of innovations that make windows and doors more comfortable to operate by people of all abilities.

Window-lifting lock: This feature (pictured above) moves the locking mechanism on a single-hung window from the check rail to the bottom of the sash. The human-centered benefit is that it creates easier access to open the window for all.

The idea for this lifting lock feature began with commercial projects, where windows can be extremely large. People struggled to reach the locks on these windows when it was not easy to access.

Many homeowners also struggle with trying to reach the check rail or lock on single-hung windows, especially when windows are located over a kitchen sink or otherwise not easily accessible. It can be so challenging to close them that some homeowners have had to get creative with their solutions, using long poles to reach the lock. Using this alternative lock can create a more comfortable, ergonomic window operation.

Low-profile door sill: A lower-profile door sill is another example of innovations that make life easier and more comfortable for all. Low sills create smoother transitions from indoor to outdoor spaces when indoor and outdoor surfaces are on the same plane. Low-profile sills minimize the potential for a tripping hazard for elderly adults, young children, and those with limited mobility.

Lock status system: Throughout history, we humans have always desired to feel safe in our homes. Today’s technology might provide some with a greater sense of comfort. Sensors that tie into the security system and indicate if a window or door is locked is one example of simple security that brings comfort to custom-home clients. Ideally, the system is an integrated part of the window design and is not an add-on assembly that needs to be covered with a plastic panel. The highest-quality windows manufacturers design the system into the architecture of the window, making it seamlessly invisible yet providing peace of mind.

Conclusion

When the designer of a custom home considers the occupants’ well-being, the principles of biophilic design should come into play. Humans crave nature. We need nature to feel good and be healthy. Windows and doors play an enormous role in bringing the natural light, views, natural ventilation, and comfort that make occupants feel good. Even if the custom-home clients do not even know what the term biophilia means, they will benefit, perhaps for generations, from the design and specification of the savvy designer who helps create the connection to nature we all need so much.

End Notes

¹Klein, Richard. “Anatomy, behavior, and modern human origins.” Journal of World Prehistory. 1995. Web. 25 March 2019.

²“The National Human Activity Pattern Survey (NHAPS): A Resource for Assessing Exposure to Environmental Pollutants.” Lawrence Berkeley National Laboratory. Web. 25 March 2019.

³Calabrese, Liz. The Architecture of Healing. University of Vermont. 2013. Web. 25 March 2019.

⁴Circadian Rhythms. National Institute of General Medical Sciences (NIGMS). National Institutes of Health. Web. 25 March 2019.

⁵Walton, Alice. “Your Body’s Internal Clock and How It Affects Your Overall Health.” The Atlantic. 20 March 2012. Web. 25 March 2019.

⁶Nazish, Noma. “Why Sunlight Is Actually Good for You.” Forbes. 28 Feb. 2018. Web. 25 March 2019.

⁷“Daylighting and Productivity – CEC Pier.” Heschong-Mahone Group. 2012. Web. 25 March 2019.

⁸“Daylighting and Productivity – CEC Pier.” Heschong-Mahone Group. 2012. Web. 25 March 2019.

⁹Joon-Ho, Choi. “Study of the relationship between indoor daylight environments and patient average length of stay (ALOS) in healthcare facilities.” Diss. Texas A&M University. 2007.

¹⁰James, Peter et al. “Outdoor Light at Night and Breast Cancer Incidence in the Nurses’ Health Study II.” Environmental Health Perspectives. 17 Aug. 2017. Web. 25 March 2019.

¹¹Browning, Bill et al. “The Economics of Biophilia: Why Designing with Nature in Mind Makes Financial Sense.” Terrapin Bright Green. 2015. Web. 25 March 2019.

¹²“Designing for the Power of Light: How harnessing light can lead to happier and healthier homes.” Inspired by Marvin. Marvin. 28 Dec. 2018. Web. 25 March 2019.

¹³“Applying the Wellness Principles of the WELL Building Standard to Residential Interiors.” Neocon education seminar. International WELL Building Institute. 13 June 2018.

¹⁴“Designing for the Power of Light: How harnessing light can lead to happier and healthier homes.” Inspired by Marvin. Marvin. 28 Dec. 2018. Web. 25 March 2019.

¹⁵“Designing for the Power of Light: How harnessing light can lead to happier and healthier homes.” Inspired by Marvin. Marvin. 28 Dec. 2018. Web. 25 March 2019.

¹⁶Tietjen, Gretchen E. et al. “Headache symptoms and indoor environmental parameters: Results from the EPA BASE study.” Anals of Indian Academy of Neurology. 2012. Web. 25 March 2019.

¹⁷Smedje, Greta and Norback, Dan. “New ventilation systems at select schools In Sweden—effects on asthma and exposure.” Archives of Environmental & Occupational Health: An International Journal. 2000.

¹⁸Saadatmand, Vahid et al. “Effect of nature-based sounds’ intervention on agitation, anxiety, and stress in patients under mechanical ventilator support: a randomised controlled trial.” International Journal of Nursing Studies. July 2013.

¹⁹Alvarsson, J.; Wiens, S.; and Nilsson, M. “Stress Recovery during Exposure to Nature Sound and Environmental Noise.” International Journal of Environmental Research and Public Health. 11 March 2010.

²⁰Weber, S.T. and Heuberger, E. “The impact of natural odors on affective states in humans.” Chem Senses. 18 March 2008.

Kathy Price-Robinson specializes in writing about homes, construction, and architecture. Her series “Pardon Our Dust” ran for 13 years in the Los Angeles Times. www.linkedin.com/in/kathypricerobinson