On almost any given block in New York City, it’s easy to see how things have changed in architecture and construction over the decades. Historic buildings like the New York Public Library or Grand Central Station are noted for their exterior artistry, and sometimes seem to be at aesthetic odds with brand-new glass and steel towers. The glass and steel buildings, though impressive, serve as reminders that today efficiency trumps artistry.
Wood to Stone to Glass
Following the Great Fire of 1835, residential building construction in the city shifted away from the wood-frame houses of the city’s early days toward quarried stone and brick. Sandstone, limestone, and brownstone (which is actually a type of limestone that owes its hue to rust), became the preferred building materials, and as quarrymen dug deeper into the earth, they also harvested granite and marble. In the hands of skilled craftsmen, these materials became works of art; richly ornamented cornices, lintels, and even gargoyles.
The materials were expensive, but in the days when the city’s historic buildings were built, labor was cheap. As Howard Zimmerman of Manhattan-based Howard Zimmerman Architects PC, points out, some of the city’s most notable buildings were built with thousands of workers. With so much money saved on labor, it was much more feasible from a business perspective to use expensive materials.
Eventually, union organization allowed workers to earn higher wages. With labor costs no longer negligible, building developers began to explore building materials that were cheaper than quarried and carved stone. Brick became the industry standard for residential architecture and prevailed until the mid-20th century, when glass made the jump from commercial to residential construction. The shift to glass coincided with technological advancements in the material itself. Typically, thick stone walls were known for their insulating capabilities, effectively trapping both warm and cool air, and helping to regulate the buildings’ interior climate.
Developments in glass paneling greatly increased glass’ insulation capabilities, making it a viable option for residential buildings. Modern exterior glass panels are usually constructed of two or three sheets of glass separated by an air space. The gas inside the space is usually oxygen, though argon gas is sometimes used to increase the panel's thermal performance. Insulation can be added via a film or “low-E” coating, which helps prevent the emission of heat.