By Andrew Spaunhurst
Precommitment
activities are the stages of the development process that occur before the
developer has committed significant resources to the project. Subsequently postcommitment activities are
the stages of the development process that occur after the developer has
committed significant resources to the project.
“If the project has not been killed during the precommitment stages of
the process, the developer is now ready to champion the deal. After crossing into the postcommitment stage
the developer puts all its force and energy into the project’s success” (Diaz
& Hansz, 210). Postcommitment stages
include designing the project, constructing the project, and managing the
asset.
Throughout the precommitment
and postcommitment stages there are three common types of estimates. They are the conceptual estimate, preliminary
estimate, and detailed or final estimate.
According to Construction Estimating Using Excel the conceptual estimate
is an estimate prepared while the project is still in a conceptual state. The conceptual estimate is used to study the
feasibility of a project or to compare two potential design alternatives (for
example, a concrete structure versus a steel structure or three stories versus
four stories). These estimates are based
on a very limited set of drawings, which are produced by the architect. The preliminary estimate is an estimate
prepared from a partially completed set of drawings, usually 35%-50%
complete. It is used to check to see if
the proposed design is on budget and to identify changes to the design that
need to be made to meet the budget.
Final or detailed estimates are used to prepare bids and change orders,
order materials, and establish budgets for construction projects.
Construction of the
building must comply with local zoning ordinances and building codes. According to Construction Materials, Methods,
and Techniques, building codes regulate the design and construction of
buildings and provide minimum standards to safeguard life, limb, health,
property, and public welfare. Codes
control the design, construction, use, and occupancy of buildings and the
location and maintenance of the buildings within their jurisdiction. In some cases equipment is also regulated by
code. Local and state building
ordinances typically adopt one of the four model codes: The Uniform Building Code (UBC) published by
the International Conference of Building Officials (ICBO), the Standard
Building Code (SBC) published by the Southern Building Code Congress International
(SBCCI), the Boca National Building Code (BOCA/NBC) published by the Building
Officials and Code Administrators International, or the International Code (IC)
published by the International Code Council (ICC).
During the
construction process detailed scheduling techniques are implemented to make
sure the project is delivered on time and under budget. The two main purposes of scheduling are to
force detailed thinking about the constructability of the project and also to
improve communication between the project managers, the owners, architects,
general contractors, subcontractors, engineers, and inspectors. Project schedules can take many forms and
range form simple to complex. Simple
schedules include bar charts and include minimal amount of information such as
activity name and duration of each activity.
Bar charts fail to link each activity by their relationship, for example
the reader will not know if one activity must finish in order for another to
start. More complex schedules such as
the Critical Path Method (CPM) arrange activities in a logical order. In the picture below the activities are
arranged according to a start-to-finish relationship. The activities that are highlighted are those
that are critical to the project. An
activity is critical to the project if it cannot be delayed. In other words if the activities highlighted
take longer than expected than the whole project will be affected. The activities that are not highlighted are
not considered critical and can be delayed without impacting the overall
completion date f the project. Schedules
can also be coupled with cost and resources.
The graphs below are based off of the CPM schedule with loaded costs and
equipment.
As you can see
once the construction part alone of entrepreneurial activity has many aspects
and cannot be completed by one person.
Investment activity as a whole requires the work of many individuals and
many agencies in order to construct only one project. It is the countless hours of work by many
individuals that contribute to our built environment and is something every
person benefits from.
Sources:
Diaz, Julian III & Hansz, Andrew J. "Real Estate Analysis: Environments and Activities". Kendall Hunt, 2010. Dubuque, IA.
Peterson, Steven J. "Construction Estimating Using Excel". Prentice Hall, 2012. Upper Saddle, NJ.
Spence, William D. "Construction Materials, Methods, and Techniques". Delmar Cengage Learning, 2006. Clifton Park, NY.
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