11.2 Scheduling and Project Management

The Critical Path Method

The Critical Path Method (CPM) is the scheduling technique emphasized in the business-and-project-management reference text, and it is the scheduling concept most likely to appear on the exam. CPM breaks a project into activities (discrete tasks), assigns each a duration, and links them with dependencies (also called precedence relationships) that record which tasks must finish before others can start. The result is a network of possible paths through the job; the critical path is the longest path, and its length sets the shortest possible project duration.

Worked example — a small kitchen remodel:

Two paths exist:

• A → B → D → E → F = 2 + 3 + 1 + 2 + 2 = 10 days
• A → C → D → E → F = 2 + 2 + 1 + 2 + 2 = 9 days

The critical path is A–B–D–E–F at 10 days, and the project cannot finish sooner. Activity C has float (also called slack) of one day: it can slip a day without delaying completion because its path is one day shorter than the critical path. Activities on the critical path have zero float — any delay to them delays the entire project day for day. That is the exam-ready insight: the critical path determines project duration, so managers watch critical activities first and reallocate labor to them before anything else.

Distinguish two kinds of float. Total float is the delay an activity can absorb without delaying project completion; free float is the delay it can absorb without delaying the very next activity. When a non-critical activity consumes all its float, it becomes critical — and the manager suddenly has two critical paths to defend. Any change in durations or dependencies means recalculating the whole network, because the critical path can move.

Updating and Compressing the Schedule

A schedule is a living document, updated as actual progress replaces assumptions. When a project must finish faster, the two compression tools are fast-tracking — running activities in parallel that were planned in series, which raises rework risk — and crashing — adding resources such as overtime or extra crews to shorten activities, which raises cost. Both only help when applied to the critical path; shortening an activity that has float buys nothing. Compare the CPM network with a simple bar chart (Gantt chart), which shows activities as horizontal bars against a calendar — easy for homeowners to read but weak at showing dependencies. Many contractors use both: the Gantt chart for communication, the CPM logic for control.

Milestones

A milestone is a zero-duration marker flagging a significant event — permit issued, rough inspection passed, substantial completion. Milestones anchor the schedule to contract dates and give the homeowner visible checkpoints. Substantial completion is the milestone with legal weight: it generally marks when the work is usable for its intended purpose, triggering final-payment obligations and warranty clocks.

Supervision Duties

The MHIC license holder is responsible for supervising the work — Maryland expects the licensed contractor to control the job even when subcontractors perform it. Day-to-day supervision means sequencing trades so nobody trips over the schedule, confirming materials arrive before the crew that needs them, enforcing site safety, and verifying that only properly licensed trade contractors (electricians, plumbers, HVACR) perform regulated work. A supervisor who discovers a schedule slip early has options — resequencing, adding crew, working Saturdays; one who discovers it at the deadline has only excuses.

Quality Control and Inspections

Quality control (QC) is the contractor's own system for verifying that work meets the plans, specifications, and code — checklists, photo documentation, and hold-point inspections at stages where later work covers earlier work. The classic hold point is rough-in: plumbing, electrical, and framing must be inspected and approved before insulation and drywall conceal them. Closing walls early risks a failed county inspection and expensive demolition. The contractor must also schedule and pass required county or municipal inspections; the permit holder, not the inspector, bears responsibility for calling for inspections.

Communication and Documentation with Homeowners

Home improvement disputes investigated by MHIC are disproportionately documentation failures. Protect both parties with:

• A written contract with a clear scope, price, and payment schedule
• Change orders — written, priced, and signed by both parties before changed work is performed
• Daily logs recording work performed, crews on site, weather, and deliveries
• Photographs of conditions before, during, and after the work
• Written confirmation of homeowner selections and approvals

Verbal approvals evaporate the moment a dispute reaches the Commission. The rule of thumb that wins exam questions and arbitrations alike: if it was not written down, it did not happen. These business and project management practices track the NASCLA Contractors Guide to Business, Law and Project Management, the reference text listed in the PSI candidate bulletin for the business portion of the examination.