In the early 1970s, Peer and Selinger developed a linear scheduling method in the process of analyzing parameters affecting construction time in repetitive housing projects (Johnson 1981). This method became known as the construction planning technique (CPT) and has been applied to projects with discrete activities as well as linear activities. Peer (1974) further proposes that planning the construction process is not a problem of finding an incidental critical path fiom arbitrarily determined single activity durations.
On the contrary, one of the main steps in planning production is to define what should be made critical. This may be dictated by cost considerations or shortage of certain skilled labor. Peer (1974) states that many methods of including resource allocation in network analysis have been employed, but that all of these programs remain sophisticated only from a theoretical point of view and are not capable of changing the original unrealistic schedule into a practical solution for the site.O’Brein (1975) proposed a method of scheduling repetitive units (floors of a high-rise building) called Vertical Production Method (VPM).
He states that when the high-rise project reaches the first typical floor, the whole project momentum shifts gears. Even though each floor becomes an individual project with a well-defined start and completion, the schedule is no longer determined simply by the length of that project per floor. Rather, the schedule is now controlled