Scope of work is the often the missing element in a project that can make your project stay on track or completely derail from it.
A project will always have these three components that co-exist among each other: cost, schedule and scope of work. These are highly interrelated, meaning that if one changes, at least one of the other two will be modified as well.
At its core scope of work is the deliverable that will be completed once the project/task is finished. The deliverable has intrinsic characteristics like quality (e.g. materials) that are mainly driven by its design.
Design is a phase in a project that is easy and inexpensive to make any type of modifications. As the project matures towards the construction phase, design for scope of works becomes defined enabling cost and schedule estimates be calculated.
The project owner (influenced by the tenant or whomever is going to operate the asset) needs to provide input to the design team with the objective of defining the scope of work. Having a defined scope of work with all the possible details (e.g. specifications, requirements) will ensure the planning efforts regarding cost and schedule estimates remain accurate during the execution phase.
In addition to quality, there are other aspects to consider when thinking of the "how" the scope of work is going to be built. The most relevant function to consider is safety.
Scope of work is an element that brings context to a project's performance indicators by providing a reference of what has been achieved from a deliverables perspective when compared to schedule and cost performances. The usual trap is that stakeholders will only pay attention to the cost or schedule indicators without considering scope of work and that is a mistake. As a best practice, anytime you are referring to cost or schedule, don't forget to bring scope of work into the equation.
For the most part, a cost overrun or a schedule delay is a symptom from it's underlying root-cause related to scope of work. As it was mentioned earlier in this article, these three components are interrelated and any tweak will impact the harmonious balance among them.
In context to this article, the main way to avoid a schedule delay or cost overrun is to ensure the scope of work is fully defined before any procurement or construction activities begin. There are two reasons why a scope of work may change after the design phase is completed, hence impact cost and schedule estimates. The first one is due lack of definition when it comes to detailing the specifications (e.g. type of materials) or requirements (e.g. what is acceptable as an end product). The second is that the client/tenant requirements may change in a later stage and the approved scope of work will need to be updated accordingly to meet the revised requirements.
Whenever cost or schedule is mentioned, scope of work must be immediately considered as well. The harmonious balance of these three elements will be disrupted when there is a change in any of these, and a re-balancing act will take place to bring it back to a balance.