He also becomes chairman of its remuneration committee.
Holmes is currently managing partner of the Leeds office of BDO Stoy Hayward whom he joined in 2002 from Arthur Andersen where he had been a partner since 1988.
Prior to joining Arthur Andersen he qualified as an inspector of taxes with HM Revenue & Customs.
His appointment follows the retirement from the David Mace as a non-executive director at the AGM on May 13.
In April Lookers appointed Peter Jones, former chief executive of CD Bramall and Bramall & Jones, as an operations director.