Companies owned by property developer Jim Mansfield have been ordered by the High Court to demolish car parks and aircraft hangars built at Weston Aerodrome without planning permission.
The court also ordered Mr Mansfield to pay the legal costs of South Dublin County Council.
However, the court refused to grant an order restraining Mr Mansfield from carrying out any development at the aerodrome.
Mr Mansfield has been given three months to carry out the demolitions.
In a written judgment published last month, High Court judge Mr Justice William McKechnie found in favour of South Dublin County Council , which had alleged Mr Mansfield had carried out numerous unauthorised developments on the site.
Mr Justice McKechnie "totally rejected" the claims by Mr Mansfield's witnesses that the council was taking a politically driven approach to the issue. These remarks were "wholly inappropriate" and unsupported by any evidence and the witnesses involved had "significantly strayed" beyond their area of expertise, he said.
Mr Mansfield bought Weston for €12.7 million in 2000