Zoo Glass With No Standard Details: Columbus Zoo’s North America Trek

Zoo glass shop drawings for Columbus Zoo’s North America Trek: laminated glass viewing walls in custom steel frames at five habitats, 3/8 inch steel framing at the gorilla enclosure, and no standard details to copy from.

The Zoo Glass Scope

The package:

• Custom steel framing systems designed specifically for this job
• Bear, otter, wolf, eagle, and swan enclosures with laminated glass barrier / viewing walls
• Gorilla enclosure: 3/8″ steel framing system

No storefront, no curtain wall, and nothing with a series number. If you draw storefront for a living, this is a different job with the same software. Every viewing wall is laminated glass in a custom steel frame that exists for one habitat and nowhere else. The gorilla enclosure got the heaviest frames in the set, 3/8 inch steel, for the animal on the other side of it.

Built Like a National Park

The design took its cues from visits to Yellowstone, the Great Smoky Mountains, Acadia, and Glacier, and it shows in the parts that are not habitats. There is an entrance arch modeled on the national park gateways, with a compass rose under it, and there are green roofs, vintage-style lanterns, and signage in the National Park Service style. The rockwork is hand-carved, with stacked stone edges meant to blend into the landscape, and some of the trees that came off the site went back in as perches for the animals. The region it replaced opened in the 1980s, and Jack Hanna spoke at its groundbreaking in May 1985. What opened in June is the first phase, and the region runs to fourteen acres.

Tyler Menke, the zoo’s vice president of planning, construction and facilities, told Ohio Magazine the viewing angles across the Trek were designed “so the animals could have that dominant view on us.” For the glazing, that sentence is the brief. The viewing walls sit where the exhibit design puts them, in rockwork and between log posts rather than in a stud wall, which is where the shop drawings start to differ from any other job.

Nobody Publishes a Bear Detail

On a Kawneer or YKK package the manufacturer’s standard details have already decided the bite, the glazing method, and what the head looks like. Zoo glass has no standard details, and neither does a steel frame built for one otter pool. The glass makeup and the loads came from the PE. So did the size of every custom angle and fastener holding the frames together, worked out with the PE one condition at a time, which is where this job got hard. Each habitat brought its own edge conditions from the exhibit design, and the dimensions came from the field, because hand-carved rockwork does not hold a tolerance the way a stud wall does.

So the set carries what the system details normally carry. That means angle sizes, fastener sizes, glass sizes and edge clearances, bite and setting at every edge, joint sizes, and where the glass stops and the rock starts, all drawn rather than assumed. Google gets asked how thick zoo glass is about fifty times a month, per the keyword tool. The answer on this job is as thick as the PE says, repeated on every sheet so nobody rounds it, and bite and edge clearance are written down at every lite for the same reason.

The cost of a frame with no system behind it is drafting hours. It is more sheets than a storefront job of the same square footage, with details that differ from their neighbors by an inch of rock. All of it is cheap next to a re-cut lite. If you are pricing one of these, the hours are in the steel, not the glass. Every angle and fastener has to be sized by the PE and shown on the set, and every edge gets its own detail. Figure the drafting the way you would figure custom steel, not storefront.

Glass for a Bear, Steel for a Gorilla

Laminated glass is the barrier material here for the same reason it is everywhere. The interlayer bonds two lites into one that holds its shape under impact, and it stays clear where softer materials scratch. The frames are custom steel, sized with the PE for what stands behind them, and the gorilla enclosure’s frames are 3/8 inch steel. At the otter habitat the frames land between log posts rather than in a wall, the condition in the photo above, and their dimensions came from the field like the rest.

Need a Set Like This?

MP Drafting did the shop drawings on this one. If your next job has glass holding back something with claws, or steel framing with no standard details behind it, send us the architectural set and we will scope it.

Contact MP Drafting