Hang the expense

Titanium is the new dream cladding material. Durable, corrosion-resistant, maintenance-free, flexible enough to fit complex shapes and with a chameleon-like metallic surface that shimmers and reflects changing colours in the sky, it is just irresistible to architects. And in Frank Gehry's spectacular, freeform Guggenheim Museum in Bilbao, the material could not have had a better advertising campaign. Yes, it may be expensive but in a love affair, who cares? Little wonder, then, that Foster and Partners, Richard Rogers Partnership, Terry Farrell & Partners and Zaha Hadid are flirting with the material on current projects.

This sudden passion has now been consummated. Construction has started on the UK's first titanium-clad building. The £26m Glasgow Science Centre, which is being built on Glasgow's riverfront, will be clad in 6000 m2 of 99% pure titanium sheet.

Designed by Building Design Partnership, the centre will be housed beneath a paraboloid roof clad in curved, overlapping panels that are intended to look like giant fish scales.

But titanium is hardly a new material. It has been commercially available for half a century and its hard, durable, relatively lightweight properties have been exploited in aeronautical engineering, chemical processing plants and, more recently, in luxury consumer products, such as jewellery, watches, sunglasses, bicycles and golf clubs.

Even in the building industry, titanium has been used as a cladding material for some 30 years – although only in Japan.

Simon Cardwell of Ove Arup & Partners' research and development department says: "In Japan, about 400 buildings have been roofed and clad in sheet titanium. The Japanese appreciate the material for its resistance to their very corrosive environments, with high chloride levels and even volcanic fallout." In the UK, titanium was considered as a suitable corrosion-free material for recladding the controversial eight-year-old St Mary's Hospital on the Isle of Wight, where stainless steel had rusted in the salt-laden sea air. But it was rejected as too expensive for the NHS-funded project.

For Glasgow's science centre team, however, cost was not the only consideration. "Titanium is an expensive material that costs £35-40/m2 of cladding as supplied by the manufacturer, which compares with £20-25/m2 for stainless steel," says BDP project architect Alistair Elder. "But we are using it for its design life and visual appearance. And the material is covered by a 100-year guarantee from the manufacturer." The manufacture, fabrication and installation of the titanium cladding for the Glasgow project will be a complicated process, spanning three continents and taking up to five months.

The titanium will be manufactured to a special architectural specification by Kansas-based Architectural Titanium, a recent joint venture between the two world-market leaders, the USA's Timet and Japan's Nippon Steel, that is the only supplier of construction-grade titanium to the UK.

The manufacturing process, to be carried out in the USA, will involve smelting black sands from Australia into sponge, then melting it into ingots, forging it into slabs and rolling it into sheet. The final surface finish for the science centre will be embossed by a special rolling process.

This finish is intended as an improvement on the Guggenheim panels, which were pickled in acid but still showed unsightly variation in finish, as well as the fingerprints of any admirers who touched it.

The cladding panels will be fabricated in Germany by subcontractor Mero. The plan is for the titanium to be installed in 4 × 4 m panels with a thickness of only 0.4 mm. These can take up the curvature of the roof without causing unsightly puckering at the edges. Each panel will be attached with stainless steel clips to galvanised steel sheeting, which forms part of an elaborate prefabricated sandwich panel and subframe. Once delivered to site, the fully prefabricated roofing units will be lifted on to tracks and bolted into place.

Although it may be more modest in scale and form, Glasgow's new science centre is likely to be hailed as the UK's answer to Gehry's Guggenheim.