Changes are coming to the renovated main library that may not be as noticeable as the furniture in the new addition with lighter-colored wood and more contemporary lines. According to Library Project Manager Brenda Loewen, both old and new sections “will provide an improved thermal performance, reduce infiltration, and provide LEED points while maintaining the historic appearance.”
The library’s roof will have an R value (resistance to heat loss) of 30 instead of 20; walls below ground will be insulated where they had no insulation before, giving them an R value of 7.5; and spaces between double panes in windows will be filled with inert, non-poisonous, denser-than-air Argon gas to improve thermal insulation efficiency.
The building’s indoor environment will have separate ventilation and space conditioning systems operating independently instead of together as they have in the past. Decoupling ventilation from cooling and heating will provide better humidity control, a more comfortable environment, and low cooling and heating costs.
The library is also switching to high-efficiency LED lighting which is more easily and safely recycled than fluorescent rods containing mercury. LED light fixtures require much less power than incandescent and fluorescent fixtures and emit only a fraction of the heat, lowering demand for cooling.
Chart furnished by engineering consulting firm Thornton Tomasetti, showing the projected reduction in energy usage in the new library design beyond LEED baseline certification requirements.
The upgrades to library environmental controls will reduce Energy Use Intensity (EUI) — measured in thousands of BTUs per square foot per year — beyond what is required for LEED certification. According to engineering consulting firm Thornton Tomasetti, the library’s improved energy efficiency will achieve a goal of 40.9k BTUs per square foot per year, exceeding the LEED baseline requirement of 67.9k. The greatest reduction will be in heating, where the library will use only 8k BTUs per square foot per year — less than a third of the energy LEED allows!
Tomasetti has also created a “red list” of 5 banned chemicals linked to cancer, birth defects, infertility, asthma, and other sensitivities. If building materials or furnishings contain any one of the five listed chemicals (halogenated flame retardants, formaldehyde, bisphenol A (BPA), phthalates, polyvinyl chloride (PVC), or lead) they will not be used.