ÐÇ¿Õ´«Ã½

A Because it can take a heavy load

The huge roof of the Olympic stadium in Shenyang, in the green hills north east of Beijing, is an impressive sight. But it’s not just aesthetically pleasing, it’s tough too.

Bayer Sheet Europe has developed a special polycarbonate sheet and given it a decidedly difficult name – Makrolon Multi UV 3X/25-25 ES. At Shenyang, 20,000m2 of the stadium roof are covered with the stuff and its bending flexural strength was crucial.

The sheets can carry more than three kilonewtons per m2, so the roof can withstand heavy loads of water and snow.

The installation of the sheets, which will take four to six weeks, is expected to start this spring.

www.sheet.bayerpolymers.com

B Because it’s educational

Mendip Green School in Weston-super-Mare was originally conceived with a tiled roof, but then Clevedon architect Gray Holmes & James had a change of heart. With sustainability now a mainstream idea, a greener system seemed more attractive, both environmentally and aesthetically. So the designers opted for the ZinCo green roof system, supplied by Alumasc. The green roof also acts an on-site biodiversity lab that pupils can study.

The ZinCo system, installed by W A Roofing of Bristol, consists of a series of layers with planting underlayed by an Alumasc Derbigum waterproofing cap sheet.

Water retention and drainage is provided by Floratec FS 75 on the 15º sloped areas and Floradrain FD 25 on the flat link roof.

www.alumasc-exteriors.co.uk

C Because it gives ultimate access

Britain’s largest unsupported span at 180 metres eave-to-eave, the Richard Rogers designed roof at Heathrow’s Terminal 5, carries enormous maintenance challenges.

As well as doing 1,800 metres of on-site roof welds, MR Site Services also designed, manufactured and installed lightweight roof maintenance walkways, bridges and telescopic ladders.

The 2,700 metres of walkway run across both gable ends and down the length of the spine of the roof. The design is based on the firm’s own Quantum Walkway system and is made from extruded aluminium which can be slotted together on-site. Specially engineered fixing clips fasten them to the roof and spread the load.

The firm supplied 40, five-metre long bridges to span the 3.5 metre wide roof lights that run across the roof east to west. These bridges carry the walkways and cable trays.

It also installed five telescopic ladders for use at each of the centre core access points.

www.mrsiteservices.co.uk

D Because it’s natural

For its latest development in conservation-conscious Hampshire – Still Meadows in the village of Lockheath – housebuilder Orchard Homes rejected the synthetic in favour of the natural when it selected Koramic to supply five different types of clay tile.

Two of the seven-house development use the 451 Victorian pantile – which has a weathered surface and a colour range from bright red to grey and black – while one house is tiled with the similar 451 Victorian braised blue pantile. It has a blueish tint due to controlled firing, when oxygen is removed from the process.

Elsewhere, one house features VHV dark rustic, a Flemish tile with a variable gauge which makes it easier to fit; another uses FD antique, a pantile with a 10 degree pitch, while the remaining two houses are roofed with the 309 Heritage medium handcrafted clay tile.

www.koramic.com

E Because it fits in

Adjoining the grade II-listed Wordsworth Museum and close to the poet’s former home, Dove Cottage, is the newly-built Jerwood Centre in Grasmere, Cumbria. It houses books, manuscripts and artwork from Wordsworth and the Romantic period. The RIBA Award-winning building features Burlington’s pale green Elterwater slate laid in diminishing courses on the roof of the main building.

The concept for the building came from architects Benson & Forsyth, which was charged with creating a 21st century edifice in traditional Lakeland materials. Napper Architects was then appointed to take forward the concept and make it a reality.

www.burlingtonstone.co.uk