Helping to create bright, comfortable spaces in a state-of-the-art public library
Calgary’s New Central Library will be a vibrant hub in the city’s East Village. In addition to housing a collection of 600,000 books, the 240,000 sq. ft. facility will be a multi-purpose destination and gathering place, with amenities that include a 340-seat theatre, a large café, numerous technology hubs, and welcoming reading rooms--all situated around a large, open atrium. Two complementary design choices -- the openness of the interior and the striking transparency of the building’s façade -- are intended to let daylight fill the entire library.
The library will be clad with a unique curtain wall system composed of hundreds of high-performance glazing segments in several polygonal shapes. The design plan called for the shape and material of the glazing segments to correspond to the function of the adjacent interior spaces -- so that each glass segment transmits an appropriate amount of light for the activities people inside that part of the building will be engaged in. The goal of this design strategy is to create an energy-efficient building with a beautiful façade, as well as interior spaces where light levels and temperatures are comfortable for library patrons.
The building’s designers, DIALOG of Calgary and Snøhetta of New York, came to us for help with the execution of this design plan: they needed analysis that would help them understand and precisely quantify the visual impacts of their proposed distributions of the opaque, clear and fritted panels across the façade.
Having gained a complete understanding of the lighting effects the designers wanted to achieve, we developed a plan for a comprehensive glare and daylighting analysis.
We began by studying the various façade materials and the light they transmitted, taking into account the multiple frit types and patterns of the glass products. We also examined the light levels at the library, and calculated the potential for glare under various weather conditions and at different seasons and times of day. Finally, we considered the activities patrons and library staff would be engaged in in different parts of the library building--from reading print materials to using computer screens to chatting in the café--and considered how the various glazing options could create comfortable conditions for those activities.
Once we understood the local effects of particular glazing selections, we put the insights together in a whole-building, state-of-the-art daylight modeling. To ensure that the building would function well at all times of day and in all seasons, we assessed daylight levels for every hour of the year using climate-based metrics that reflect the changing sky conditions at the site.
In addition to delivering the technical performance information from our analysis to the designers, we also produced hourly daylight visualizations that would help library leaders, city officials and members of the public see what kind of atmosphere the intricate façade would create inside their new library. This helped both the client and the public see the implications of the designers’ choices before the library was constructed, and helped to build anticipation for the completion of an ambitious public project.
Our daylight modeling work informed the design of the façade, the placement of particular amenities within the building and the selection of interior finishes. When the library opens in late 2018, users of the large, open reading areas will find their pages bathed in natural light while spaces with computer stations for staff and patrons will have the moderate light that supports screen clarity. Like Calgary’s library patrons, our daylighting specialists look forward to the opening of the city’s most significant civic building in 25 years.