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NCCTP - The Network for Construction Collaboration Technology Providers

Cadweb

Case studies

Portman House, Oxford Street
Greenpark

Portman House, Oxford Street

This case study describes the £30 million high profile refurbishment of Portman House in London’s Oxford Street, a 9,385 sq m (101,000 sq ft) office development. Work started on site in February 1999 and was completed in September 2001.

Client - Land Securities

Developer Land Securities looked at a number of systems for this project and chose Cadweb because it offered the security of a complete audit trail and a system that could be relied upon. It saw the Portman House project as an opportunity to trial Cadweb, and therefore used it only for certain document types, including drawings. Other documents were circulated using traditional paper-based methods.

The refurbishment of the 1950s Portman House involved complete demolition and reconstruction above second floor level. A new structural steel frame and composite floor were installed to create six new floors, and the refurbished building clad in a combination of curtain walling and Portland-style reconstituted stone. HBG Construction Ltd won the £30 million contract to refurbish the building to shell and core and install all major services. The firm was appointed under a two stage tendering process and worked to a traditional JCT contract.

“The main benefits were Cadweb’s speed and security, and the automation of processes that previously took designers away from the design process.”

Andy Godfree - Architect, Sheppard Robson

The project was complex because of the tight city centre location, the ground floor shops which had to be kept serviced and operating throughout the project, and changes to the design as the project progressed. Decisions like turning the basement - originally intended to be new retail space - into a car park can cause project delays, due mainly to the time taken to distribute new design information.

All the designers and the 10 major subcontractors were linked directly into Cadweb. A full audit trail was created for every document that included details of every revision, when the document was retrieved and when it was opened. HBG’s project co-ordinator received design information from the architect and engineer on the Cadweb system and then disseminated it to subcontractors and site staff as appropriate. He says the main advantages are the system’s simplicity; the time savings and the audit trail: “People can’t blame the post any more - if they don’t have a document it’s because they have failed to open it up.” This point was emphasised during a postal strike in 2001, which could have caused havoc if the project was reliant on a paper-based system.

Mouchel Consulting’s staff found the audit trail particularly useful. They knew what drawings had been issued, and that there could be no argument that other parties had received them, because they could check it through the system.

All the project drawings produced by architect Sheppard Robson, structural engineer Mouchel and building services engineer Jaros Baum & Bolles were issued through Cadweb. More than 50,000 project documents and drawings went through the system, including 10,000 different drawings and their revisions. The cost of print and postage for these would come to around £75,000.

The use of Cadweb on the project means tenants have instant access to the “As Built” record set and the “Operations and Maintenance manuals”.

Cadweb is also now being used on Land Securities next development, Whitefriars Shopping Centre in Canterbury, for all project information.

Greenpark