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How skylights contribute to energy efficiency in the This Old House Modern Barnhouse

Skylights provide passive lighting and ventilation to reduce reliance on electrical lighting and HVAC.

a stairwell brightened by a skylight white walls and blond wood floor

One way to make your home more energy efficient is to reduce your reliance on electric lighting, heating and air conditioning, and skylights can help by providing passive lighting and ventilation. See how designer and owner Amy Matthews designed passive lighting and ventilation into the 2021 This Old House Modern Barnhouse.

What is passive lighting?

Instead of relying on electrical lighting, passive lighting means sunshine through skylights or windows brightens the interior enough for daily activities. By keeping the lights off and relying on natural light, homeowners can save on electrical lighting bills.

In the Modern Barnhouse, Matthews amplified the natural light coming in through skylights and windows by designing the interior with white walls and white oak floors to allow the light to bounce around the space.

“One of the main goals was to capture as much light in this home as possible,” Matthews explained. “I knew I needed to do that through not only the windows, but the skylights. The way the skylights work, especially placed on the southern exposure in the house, is that they enable the space to get flooded with light at all times of day, but they also add a passive property to the cooling in this space, which is really important to me, because the whole entire structure is built super efficiently with SIP (Structural Insulated Panel) walls.”

In northern locations like Minnesota, where the Modern Barnhouse is located, passive lighting can also help reduce wintertime heating costs because sunshine through windows and skylights creates heat inside. In the summer, the skylights have remote-controlled shades that diffuse the sunlight and prevent overheating.

Bathroom skylight closed partial shades

What is passive ventilation?

When Matthews talks about passive cooling, she’s referring to passive ventilation, which means that she can create airflow in the house without turning on a mechanical system powered by electricity. Sometimes passive ventilation is called the stack effect or chimney effect, and here’s how it works.

When you open a skylight on the roof and a window below, the hot air that rises and accumulates at the ceiling escapes, while cooler air is drawn in through the window below. In the Modern Barnhouse, the stairwell provides the optimal location for a solar-powered, fresh-air skylight to perform this essential function because it’s in the center of the home.

Stairwell open skylight shades rug plant

Opening the stairwell skylight draws air from throughout the house to create natural ventilation and refresh the whole home. Matthews explains:

“There was a very hot day on one of the first days we had the house closed up; it had gotten hotter than expected, earlier in the season. Everything felt stagnant in the house. As soon as I opened the skylight, there was air movement. It wasn't like a wind tunnel; it wasn't like a rush of air or a strong breeze blowing through, but it was as if there was the escape of all of that hot stagnant air, it just moved straight through and out the roof. So it instantaneously not only cooled, but it just allowed the heavy air to be released, and that created comfort.”

Open skylight white ceiling blue sky

And Matthews doesn’t need to worry about leaving her skylights open because they have an integrated rain sensor that will close them at the first sign of inclement weather.

Can skylights with shades be automated?

Home automation is growing in popularity and skylights are part of this trend. The VELUX Active system enables VELUX solar-powered skylights and shades to be automated to open and close without any homeowner interaction. Here’s how it works:

  • Internet weather station - The skylights and blinds are connected to an online weather station.
  • Indoor climate sensor - The system includes an indoor sensor that monitors temperature, humidity and CO2 levels.
  • Active setting - On the “active” setting, the system compares the weather outside with the indoor conditions, and automatically opens the skylights to bring in fresh air, if doing so will cool the space, reduce humidity or bring down CO2 levels. It will also proactively extend the shades to provide an added layer of insulation against hot, sunny summer days or cold winter nights.
  • Scheduling feature - Homeowners can also create schedules for their skylights with shades, so they open and close at specific times each day.
Iphone skylight automation app

Skylights are a smart choice for energy-efficient homes.

As the Modern Barnhouse demonstrates, solar-powered, fresh-air skylights with shades have a role to play in boosting home energy efficiency through passive lighting and ventilation.

Are you ready to add smart skylights to your home? Enter the VELUX Skylights Sweepstakes for a chance to win two VELUX No Leak Solar Powered “Fresh Air” Skylights with shades and installation.

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