Letting the Light Shine on Pleasant Hill Library
One of the most important aspects of any building design is how it uses sunlight. From a technical perspective, strategizing when and where to use the sun to passively heat a high-performance building becomes a major part of the initial design phase. Designers rely on a multitude of techniques that utilize solar radiation in a way that minimizes the utilization of the building’s heating and cooling systems while also optimizing thermal comfort. On the one hand, they want to trap significant amounts of solar radiation during the coldest months to minimize use of the mechanical heating systems. On the other hand, they want to avoid trapping all that heat when it’s warm to avoid overheating and expending too much energy on active cooling measures. As a result, building orientation, shading techniques, glazing element placement, and the use of specialized films all contribute to finding the right balance.
Of course, these more technical elements of construction are not the only aspects that go into creating high-performance buildings. In addition to being efficient, high-performance buildings seek to create comfortable spaces, and comfort does not begin and end with thermal performance or even continuous ventilation. There are multiple factors that go into making a space feel welcoming, and chief among those is providing ample natural light. High-performance construction may require conscientious placement of glazing elements, but one need not necessarily block the warmth of natural lighting to keep a building cool—even in warmer climates.
A case in point is the Pleasant Hill Library, which is located in California’s East Bay. Opened in 2022, the library may not be targeting Passive House certification, but designers Bohlin Cywinski Jackson have aimed for net zero energy certification, meaning the building will consume as much energy as is produced by renewable sources. To achieve this goal, the building will rely on renewable energy generation, as well as a combination of efficiency measures and other offsets. The library also showcases how high-performance construction techniques can be used to create truly welcoming, versatile, and airy spaces that are full of natural light.