Early in the schematic phase of construction projects there is an opportunity to impact the project budget using constructability reviews. Decisions made at this point in the project may be incorporated in the documents rather than modifying plans and specifications at the end of the project. Examples of constructability reviews include the exterior envelope of a hospital tower, construction methodology used to construct a Linear Accelerator Vault, and structural options to cover a 100 ft square open courtyard.

In the initial example, the exterior envelope of a hospital tower was proposed to be metal studs with brick veneer. The Designer was concerned about the availability of masons in the area to install the brick veneer. Sample budgets and schedules were built for the proposed design and for an alternative design using pre-cast concrete panels. After reviewing the cost and schedule information, it was discovered the pre-cast option would reduce construction time by approximately 60 days and project budget by approximately $180,000. The decision was made to use the pre-cast option prior to the design of the foundation allowing for the foundation design to specifically accommodate the least cost building envelope option.

In the second example, a second vault was required for a cancer treatment center to accommodate a new linear accelerator. As is common to most projects there were time constraints. Typical construction methodology requires an elaborate shoring system to support the 3'' to 6'' thick concrete roof and the shores must remain in place for up to 30 days while the concrete matures. Prior to design an alternative method was proposed to support the concrete roof. The option allowed for only two interior supports. The supports were placed so that interior construction could begin immediately after the concrete was placed, eliminating a 30 day delay. Construction started with groundbreaking on 25 September and installation of the linear accelerator started on 4 January. Decision to use the alternative system was made before the structure was designed eliminating duplicated effort incurred with a design change.

The third example centers on the enclosure of an interior courtyard, allowing for additional year-round cafeteria dining. The building surrounding the interior courtyard was to remain occupied during construction and the designer was concerned about hoisting material over occupied space. A constructability review was conducted evaluating the proposed construction of concrete columns and space frames. A schedule was developed and preliminary estimates created. Two alternative systems were also evaluated with the decision to modify design to steel pipe columns for support and a bow truss system to span 100''. This option reduced the cost of the project approximately $100,000 and project duration by 30 days. The new system allowed for hoisting to take place during brief un-occupied periods.

Every project presents an opportunity for a constructability review. Several key elements must be present for success. First the designer must be open to the design assist methodology and recognize that constructability reviews must be conducted prior to design development. Second, the owner must understand how and when to bring construction management expertise on the project team. Third, the construction manager must be suited to the challenges of developing several "what if?" scenarios. When all three elements are present, the opportunity exists to reduce project cost at the front end of a project as opposed to removing desired elements like durable finishes and energy efficient equipment during a value engineering phase.