HGB battled nature to turn an old Yorkshire mill complex into a supermarket.
PROBLEM 1: THE BIRDS
The early morning sound of birdsong is not what you expect to hear on the average town centre site. And it would have spelt disaster for project manager Sarah Woffenden. When she moved onto site to manage the construction of a new Asda supermarket in Dewsbury, West Yorkshire, kestrels were due to begin nesting in the buildings she planned to demolish.

Every year between March and September, kestrels hatched eggs and raised their young in one of the old mill buildings Asda wanted demolished to make way for its new store. Their arrival threatened to delay the building programme by seven months, as kestrels are a protected species that may not be disturbed when nesting. Woffenden says it had implications for the budget, as well as time, as the cost could have been huge.

"We could have netted the building to prevent the birds getting in, but that would have cost £29,000 and there was no guarantee it would work," she says.

"After consultation with the Royal Society for the Protection of Birds, we decided to let the birds nest and programme the demolition around the nesting period. Thankfully, the kestrels only nested for six weeks until mid-April, meaning we kept on track with the programme and the budget, by demolishing the other buildings around them."

PROBLEM 2: WET, WET, WET
After the enabling works, project manager AYH had to battle the forces of nature again, with severe spring weather threatening to throw the programme out of whack. High winds left the roof and cladding programmes in danger of slipping behind.

"The project team was worried about the implications of the weather for the programme," says Woffenden. "So HBG, the main contractor, pressed hard to get ahead of themselves to minimise the overall impact.

In the end the bad weather had very little effect on timescale."

Keith Rayner, the construction manager for HBG, says co-operation with subcontractors was key to overcoming these difficulties.

"Asda measures the completion of its stores from when the steel arrives on site; we delivered this store in 17 weeks from steel. This is a well-worked out development programme that rarely changes, so when things go wrong it's difficult to overcome them. The only way to do it was by sitting down with the subcontractors and agreeing

to increase productivity together and re-sequence the trades. But we know these contractors well from building other Asdas, so we pulled together to get it done."

The weather also affected the ground conditions. Part-way through the contract, Asda bought a petrol station that backed onto its service yard, which meant disposing of class C contaminated material. To avoid incurring landfill tax, the material was contained on site, by lifting the level of the car park. However, the material was untouchable when it rained because it turned to mud.

"The groundworks contractor, Kiernen Construction, had to sequence the laying of the material area by area and just had to lay off it when it rained, which it did a lot in February," says Rayner. "Instead of finishing the car park with four weeks to go, as you usually do on an Asda job, we went right up to the wire. The store was finished before the car park!"

PROBLEM 3: BRIDGE HITCH
The third big challenge AYH faced was building a 15m-long footbridge to link the store to Dewsbury town centre. The bridge was to be delivered in two sections and installed by the manufacturer, CTS. For this, a 350-tonne crane had to be put in place after the initial demolition but before construction; otherwise there wouldn't have been room for it.

Not only that, but the bridge foundations and the store foundations were different types of piles: in situ concrete piles and vibro compaction piles respectively. They couldn't be placed next to each other as that could have caused ground disturbance.

"The position of the piles was crucial," says Rayner. "It had to be worked out in great detail or it could have caused the ground to rupture."

The store opened on time in June and Owen Hickey, general store manager at Asda Dewsbury, is glowing in his praise for AYH and HBG.

"I can't sing their praises enough on this job. Both companies have had a first-class attitude and done a first-class job. I've worked with both in the past and it's not always been the case, but on this job they've really delivered."

And the glowing references don't stop there because the same project team has been awarded the contract to build another Asda in Bishop Auckland, this time in 16 weeks from steel.

"We thought that if we could do this store in 17 weeks with all the problems with the weather, we could do another in 16," says Rayner. "You're only as good as your last job with Asda. It's continually striving to improve and innovate and it brings that attitude into its construction programme. If you don't deliver, you won't work with them again."

Related files/tables