Campbell Park’s award-winning stage canopy has become a “pre-design” model for the manufacturer.
By Lynn Keillor
The English city of Milton Keynes, about 45 miles northwest of London, England, was plotted and built as a modern town in the 1960s: a place for cramped Londoners to make a new home, with streets in a grid pattern, modernist buildings and ample green space. The city’s popular Campbell Park now has its own modernist upgrade, with a new stage canopy designed and built by Base Structures Ltd. of Bristol, England. The structure received an IFAI 2012 Award of Excellence in the category of “Free-Standing Structures Under 112 Square Meters” at IFAI Expo 2012 in Boston, Mass., one of two awards the company received.
Not only did it win an award, but Base Structures also sees ongoing sales potential in this stage canopy because of its attractiveness and functionality. It’s been named “Blencathra” after a mountain range in England’s Lakes District, and is now marketed as a pre-design model. It’s one of the larger, more complex pre-design structures in the company’s offerings.
From concept to finished project, Campbell Park’s stage canopy had a fast turn-around, says Base Structures architect Kevin Hemmings. Base Structures placed a bid for the project in November 2011 and finished the work in April 2012—just in time for the spring and summer season. It was part of a series of park improvement projects in early 2012.
When Base Structures started the project, the park had an existing performance area with an outline for a stage. The initial twin-arch concept was designed by Milton Keynes-based architectural firm Hinton Cook Architects, and then furthered by Hemmings and engineer Neil Holloway. The final design, with a 7.3-meter high arch in front and a 6.3-meter high rear arch, provides the needed cover for a 12-by-12 square meter area. The base width is 17 meters.
The company opted to use Verseidag B4617 Type 2 PVC polyester fabric with a weldable PVDF lacquer in the construction. The fabric’s estimated 18- to 20-year life span met the client’s specifications; Base Structures uses the waterproof, UV-resistant fabric in approximately 70 percent of its output. A total of 254 square meters of fabric was used to cover the 17-by-12 square meter arch space. With the fabric in place, the structure resembles a saddle.
The fabric concept was an easy sell to the Milton Keynes Park Trust, which oversees park operations. “I think they took our advice,” says Hemmings. “They were interested in the color and translucency, so it was a combination of price and design life behind the decision to choose PVC polyester.”
The supporting arches are made of steel, which were challenging to install due to the angled design. Cables and tensioners are also made of stainless steel.
Hemmings and engineer Neil Holloway developed the final structure, keeping in mind the stage’s purpose and public location. The completed project stayed within budget, which was less than £80,000 ($127,000). “It think it was a sensible budget,” Hemmings says.
The stage is all-purpose, but often hosts musical acts and theater performances. It was neither practical nor aesthetic to incorporate permanent lighting gantry into the design, but lifting points were added to the arches. “Most touring groups bring their own lighting and lighting trusses so they can just winch it up with the lifting points,” Hemmings notes.
They incorporated the concept of removable rear and side walls, primarily to discourage vandalism. The walls can be put in place for a performance, and include zipper doors for stage left and stage right entrances and exits. These panels also needed to be PVC fabric, which stands up better to removal and storage.
Perfecting the side panels was a challenge, Hemmings says, because it was difficult to maintain the attractive, taut fabric tension when the access doors were unzipped. “As a stand-alone object, when it’s not being used it has a quite elegant look about it,” Hemmings adds. “Also, what’s critical, is that there’s no fabric below three meters. It’s in open parkland and it could be quite vulnerable to vandalism.”
Park staff have been trained to install and remove the additional panels—the most important step being to make sure the panels are dry before going into storage, Hemmings says. As few as two people can manage the job, which takes approximately four hours to complete. The panels slide into an aluminum track and are tensioned into sockets in the concrete stage.
Since it’s an outdoor stage, Hemmings made concessions for the elements. “All the rain water collects at the two sides and goes down inside the tubes to an underground drain, which means water does not drip over the edges,” Hemmings explains.
Minor issues popped up during the summer months that Base Structures will address before next spring, Hemmings notes, including some new paint and covering up a drainage pipe. Otherwise, both Base Structures and the Park Trust have been pleased with the results. “It performs to their expectations,” Hemmings says. “They’re very happy about what this means they can do in the park.”
Have design, will option
At this point, no other client has purchased the design for the Blencathra structure, but Hemmings sees potential for the design as a stage canopy in other parks or amusement parks, or as a cover for an outdoor market or covered seating area.
“It’s not designed as a touring structure, that’s for sure,” he says, “although it could be easily taken down and put back up again if someone wanted to relocate it.”
The pre-designed model carries a few optional variations, including a high translucency silicone-coated glass fabric, which has a design life of 25 years. Lighting, heaters and other sizes are additional options. Since the Blencathra has already gone through the design process, the pre-design price comes at an approximate 12 percent discount in comparison to the original Campbell Park version.
This project is one of the more modest-sized pieces from Base Structures. The company also created and built several structures for the 2012 Olympic Games in London, including the basketball arena and three relocatable shooting ranges.
“Any small project has to go through exactly the same processes as a large project,” Hemmings says. “Curiously enough, some of the small projects have more design work than some of the more simple, repeatable large structures.”