Project Integration of Program & Systems: Plan, Section, and Stack
Integration questions ask how program, structure, and systems fit together in plan and section.
Programming tools. Goals, facts, needs, and concepts frame the problem. An adjacency matrix quantifies which spaces should be near each other; a bubble diagram turns that matrix into a loose plan; blocking and stacking assign areas to floors and align vertical relationships. Traps: confusing the matrix with the diagram, or locking in a stack before checking structure and shafts.
Area accounting. Net assignable area excludes circulation, structure, and mechanical space; gross area includes everything. Efficiency ratios of 75 to 85 percent are typical for offices, lower for laboratories and hospitals. Schedules and code calculations almost always use gross or construction area, so convert early to avoid errors.
Structure and module. A structural bay should accept the largest program module and the HVAC distribution. Section coordination is where most failures occur: structure, ductwork, sprinklers, lighting, and ceiling must all fit within floor-to-floor height.
Digital coordination. BIM clash detection resolves duct-versus-beam conflicts before construction, and vertically aligned shafts reduce cost and risk. Expansion, phasing, and future fit-out should be planned rather than discovered.
Worked example: a 40,000 net sf program at 80 percent efficiency needs 50,000 gross sf. On five floors that is 10,000 gross sf per floor. A 30-by-30-ft bay gives 900 sf, so 10,000 ÷ 900 ≈ 11 bays; a 3-by-4 grid of 12 bays provides 10,800 sf, covering the program with a module the ceiling and parking grids can follow.
Project Costs & Budgeting: Estimating Method, Contingency, and Life Cycle
Cost questions test whether you can choose the right estimating method and compare alternatives on a consistent basis.
Estimating methods. Order-of-magnitude estimates from cost per square foot are used in early design and carry wide ranges, commonly −30 to +50 percent. Assembly and unit-price estimates become possible as drawings develop; competitive bids come last. Parametric models adjust a benchmark cost for location, time, and building type.
Hard and soft costs. Construction cost is only part of the budget. Soft costs - design fees, permits, testing, legal, and owner costs - often add 25 to 35 percent, and land, FF&E, and financing may sit outside both. Traps: comparing a construction cost per square foot against a total project budget, or using net area for a metric defined on gross area.
Contingency and escalation. Contingency covers unknown scope; escalation covers inflation between estimate and construction. They are separate line items, and applying contingency to an already-escalated figure double counts. Contingency should shrink as design progresses.
Life-cycle cost. Compare alternatives on present value of first cost plus energy, maintenance, replacement, and residual value. Simple payback ignores everything after the payback point, so it favors short-horizon decisions.
Worked example: chiller A costs $400,000, uses $60,000 of energy and $10,000 of maintenance per year; chiller B costs $550,000, using $45,000 and $8,000. Over 20 years at a zero discount rate, A totals $1,800,000 and B totals $1,610,000, so B wins; simple payback on the $150,000 premium is about 8.8 years.