(a) General rule.--All actions to recover any or all damages against any person engaged in the practice of landscape architecture occurring as the result of any deficiency, defect, omission, error or miscalculation shall be commenced within 12 years from the time the services are performed. Any such action not commenced within this 12-year period shall be forever barred. The cause of action shall accrue upon substantial completion of the project. Nothing in this section shall be construed as extending the period prescribed by the laws of this Commonwealth for the bringing of any action. The term “practice of landscape architecture” shall be the same as defined in the act of January 24, 1966 (1965 P.L. 1527, No. 535), known as the Landscape Architects' Registration Law.¹

(b) Exception.--The limitation prescribed by subsection (a) shall not be asserted by way of defense by any person in actual possession or control, as owner, tenant or otherwise, of such an improvement at the time any deficiency in such an improvement constitutes the proximate cause of the injury or wrongful death for which it is proposed to commence an action or proceeding.