William Anderson, of Lancashire-based practice Anderson Associates, is demanding damages of up to £100,000 for copyright infringement and design rights over the plans at the centre of the dispute.
He alleges that his designs have been copied by architect for the development scheme, Head Roberts Associates, after B&Q falsely told the firm he had given permission for his drawings to be used at the scheme in Havant.
In his High Court writ Anderson claims that buildings and external works have been constructed on the site, and his copyright in the plans has been infringed, which is evident from overlaying the transparency of his drawing onto an aerial photograph.
Anderson claimed that he produced drawings for an expansion scheme for the site at various times since 1992, and admits that he has been paid for this work.
In March 1994, working on his own initiative and without charge to the trust which owned the site, or to B&Q, he created an arrangement of a canopy, turning, and materials-storage area, which was liked by both planners and B&Q, the writ says.
He invoiced the landowners for his fees and expenses in meeting officials and creating section, elevation and illustrative drawings, but says he did not charge for creating the plan drawings.
The writ claims he told the trust, and B&Q, that he expected to be compensated separately for this, either by being appointed and paid as architect for the project, or by other sums, and that permission to use his drawings was conditional on this.
In 1996, he valued his speculative unpaid work at £33,500 plus VAT, and offered to defer payment of this until a builder's tender for the work had been agreed, he says.
Two years later, he asked for payment of £54,000 plus VAT for his work on the scheme, and warned the trust that if it went ahead with the project without meeting his conditions, it would be in breach of copyright, the writ says. He rejected the trust's offer of £10,000 for his work as inadequate.
He told B&Q's then architect HGP that he had provided the design work for the successful site arrangement, and that the trust, B&Q, and HGP did not have permission to use his work, on which he owned the copyright.
In 2004, B&Q went ahead with developing the scheme, but without involving him or paying him, despite using his plans, the court will hear.
Anderson, says that B&Q replaced architect HGP with Head Roberts Associates, and falsely told the new firm he had given permission for his drawings to be used.
He accuses B&Q of fragrantly infringing his copyright and is seeking additional damages, as well as aggravated and exemplary damages.
By Sarah Limbrick