Contractor concedes that mistakes were made but suggests that the supermarket made matters worse

Carillion has admitted it has some responsibility for long-running problems with cracking concrete at online grocery firm Ocado’s only UK distribution centre but has suggested the supermarket has made matters worse.

As Building revealed last month, Ocado has lodged a £1.2m High Court claim against the contractor, alleging it is liable for defects with the external service yard or “slab” at the distribution centre at Hatfield aerodrome, Hertfordshire.

The slab consists of 168 concrete bays for Ocado’s fleet of delivery vans, which - according to the claim - have become progressively more cracked since it was built, making it unfit “for the purpose of the loading and unloading operations” and not destined to have a “reasonable design life”.

In a defence filed this week, Carillion agreed that the slab began to crack “soon after having been laid” and admitted the cracking was caused by its breach of contract.
It also conceded that it had omitted to strengthen the slab with a steel mesh reinforcement and had instead substituted synthetic polypropylene fibres.

However, the defence said that Ocado should be “put to strict proof that its actions (whether failure to maintain and/or to carry out repairs to the cracks or otherwise) have not exacerbated the cracking”.

“It has […] been Carillion’s understanding that Ocado was and is extremely reluctant to carry out any repairs to the slab owing to the potential for such repair work to interrupt its business,” the defence said.

It also attacked the supermarket’s plan to entirely rebuild the slab.

“It is denied that it is either reasonable or necessary to replace the slab,” the document said. “Given the nature and scope of the cracking […] the Ocado scheme is unreasonable and unnecessary and the costs associated with it are excessive.

“Carillion intends to prepare an alternative remedial scheme which will not depend on the full replacement of the slab but which will [remove] bays only where there is significant cracking.”

The defence said this scheme would be carried out at Carillion’s own cost if the “scope and programme” for such works could be agreed or determined by the court.

The case continues.