Developer British Land has called in engineer Arup to redesign its recently acquired 46,000 m2 Ropemaker Place office scheme in the City of London.

Arup is to take over the 23-floor tower after British Land bought the freehold to the site last week for £130m. The move means that Gensler, the original architect on board, has been dropped from the project.

Gensler had secured planning permission for its scheme on the 1 acre site close to the Barbican for previous owner DB Real Estate.

Nigel Webb, British Land's head of development, said that Arup would work on increasing floor space within the building but indicated that the block, which will be built speculatively, would stay within the existing planning consent

He said: "We are looking to improve the efficiency of the building, but we don't anticipate a dramatic change in its external appearance, as our overriding objective is to start on site this year for completion in the first quarter of 2009."

Construction on the site, which is already cleared, will start later this year. The build value of project will not be known until the design review has been completed.

We are looking at improving the building’s efficiency. We don’t anticipate a dramatic change to its appearance

Nigel Webb, head of development, British Land

No other consultants have been appointed to the scheme, which had been under the control of developer Helical Bar until last week's transaction.

British Land has also appointed US-based architect Leo Daly to masterplan its bid to redevelop Euston station for Network Rail.

Leo Daly's proposals will be up against plans by John McAslan/Stanhope and RMJM/Development Securities for the station overhaul. More London, Grosvenor, Chelsfield Partners and Hines are also bidding for the project.