Living Coasts in Torquay is famous for its huge, netted aviary. But how do you take care of such a vast structure? The answer – high-rise extreme knitting.
Torquay’s coastal zoo has a tented mesh roof that is 5,500 square metres in area – some 59,000 square feet, or nearly 1.4 acres. The net creates a volume of 50,000m³ or 1.8 million cubic feet of free flight for birds ranging from Inca terns and avocets to the rare South African bank cormorants.
The canopy is made of 25mm grid polypropylene fisherman’s net and held up on 35 masts, some of them up to 22 metres in height.
Living Coasts director Elaine Hayes told the Devon Week: “The net is really out in the elements – it has to endure hot sun, salt spray and howling gales. It also has to withstand birds on both the inside and the outside, not to mention the occasional attempt at vandalism.
“There are a few spots in the net that suffer more often than others. The seams between joining sections and the areas around the masts can suffer from fraying or rubbing. It’s impressive to see them working up there – though the birds don’t seem to take much notice!”
The net, which weighs about 215 grams per square metre, is checked daily by Living Coasts staff. Base Structures, the Bristol company that installed the net, and who build aviaries all over Europe, send in a team every six months to do a thorough check and routine repairs.
Andy Traynor, from Base Structures said: “Base Structures specialise in building high tensile cable net structures. This requires highly trained rope access operatives we call riggers. These guys work at great heights, in this case up to 22 metres or 71 feet. Holes appear in the net during the year and these require mending – it’s like darning socks or extreme knitting!”
Living Coasts staff can put a temporary patch over any holes that appear in the net using a large, moveable section of net affectionately known as the flying carpet. This large aviary band-aid is manoeuvred into place by halyard lines connected to pulleys on each of the steel masts.