Cost estimators collect and analyze data to estimate the time, money, resources, and labor required for product manufacturing, construction projects, or services. Some specialize in a particular industry or product type.
Cost estimators typically do the following:
Accurately predicting the cost, size, and duration of future construction and manufacturing projects is vital to the survival of any business. Cost estimators' calculations give managers or investors this information.
When making calculations, estimators analyze many inputs to determine how much time, money, and labor a project needs, or how profitable it will be. These estimates have to take many factors into account, including allowances for wasted material, bad weather, shipping delays, and other factors that can increase costs and lower profitability.
Cost estimators use sophisticated computer software, including database, simulation, and complex mathematical programs. Cost estimators often use a computer database with information on the costs of other similar projects.
General contractors usually hire cost estimators for specific parts of a large construction project, such as estimating the electrical work or the excavation phase. In such cases, the estimator calculates the cost of the construction phase for which the contractor is responsible, rather than calculating the cost of the entire project. The general contractor usually also has a cost estimator who calculates the total project cost by analyzing the bids that the subcontractors' cost estimators prepared.
Some estimators are hired by manufacturers to analyze certain products or processes.
The following are the two primary types of cost estimators:
Construction cost estimators estimate construction work. More than half of all cost estimators work in the construction industry. They may, for example, estimate the total cost of building a bridge or a highway. They may identify direct costs, such as raw materials and labor requirements, and set a timeline for the project. Although many work directly for construction firms, some work for contractors, architects, and engineering firms.
Manufacturing cost estimators calculate the costs of developing, producing, or redesigning a company's goods and services. For example, a cost estimator working for a home appliance manufacturer may determine whether a new type of dishwasher will be profitable to manufacture.
Some manufacturing cost estimators work in software development. Many high-technology products require a considerable amount of computer programming, and the costs of software development are difficult to calculate.
Two other groups also sometimes do cost estimating in their jobs. Operations research, production control, cost, and price analysts who work for government agencies may do significant amounts of cost estimating in the course of their usual duties. Construction managers also may spend considerable time estimating costs. For more information, see the profiles on operations research analysts and construction managers.
Construction and building inspectors ensure that new construction, changes, or repairs comply with local and national building codes and ordinances, zoning regulations, and contract specifications.
Construction and building inspectors typically do the following:
Construction and building inspectors examine buildings, highways and streets, sewer and water systems, dams, bridges, and other structures. They also inspect electrical; heating, ventilation, air-conditioning, and refrigeration (HVACR); and plumbing systems. Although no two inspections are alike, inspectors do an initial check during the first phase of construction and follow-up inspections throughout the construction project. When the project is finished, they do a final, comprehensive inspection.
The following are types of construction and building inspectors:
Building inspectors check the structural quality and general safety of buildings. Some specialize in structural steel or reinforced-concrete structures, for example.
Electrical inspectors examine the installed electrical systems to ensure they function properly and comply with electrical codes and standards. The inspectors visit worksites to inspect new and existing sound and security systems, wiring, lighting, motors, and generating equipment. They also inspect the installed electrical wiring for HVACR systems and appliances.
Elevator inspectors examine lifting and conveying devices, such as elevators, escalators, moving sidewalks, lifts and hoists, inclined railways, ski lifts, and amusement rides.
Home inspectors typically inspect newly built or previously owned homes, condominiums, townhomes, and other dwellings. Prospective home buyers often hire home inspectors to check and report on a home's structure and overall condition. Sometimes, homeowners hire a home inspector to evaluate their home's condition before placing it on the market.
In addition to examining structural quality, home inspectors examine all home systems and features, including roofing, exterior walls, attached garage or carport, foundation, interior, plumbing, electrical, and HVACR systems. They look for and report violations of building codes, but they do not have the power to enforce compliance with the codes.
Mechanical inspectors examine the installation of HVACR systems and equipment to ensure that they are installed and function properly. They also may inspect commercial kitchen equipment, gas-fired appliances, and boilers.
Plan examiners determine whether the plans for a building or other structure comply with building codes. They also determine whether the structure is suited to the engineering and environmental demands of the building site.
Plumbing inspectors examine the installation of potable water, waste, and vent piping systems to ensure the safety and health of the drinking water system, piping for industrial uses, and the sanitary disposal of waste.
Public works inspectors ensure that federal, state, and local government water and sewer systems, highways, streets, bridges, and dam construction conform to detailed contract specifications. Workers inspect excavation and fill operations, the placement of forms for concrete, concrete mixing and pouring, asphalt paving, and grading operations. Public works inspectors may specialize in highways, structural steel, reinforced concrete, or ditches. Others specialize in dredging operations required for bridges and dams or for harbors.
Specification inspectors ensure that work is performed according to design specifications. Specification inspectors represent the owner's interests, not those of the general public. Insurance companies and financial institutions also may use their services.
A primary concern of building inspectors is fire prevention safety. For more information, see the profile on fire inspectors and investigators.
Power plant operators, dispatchers, and distributors control the systems that generate and distribute electric power.
Power plant operators, distributors, and dispatchers typically do the following:
Electricity is one of our nation's most vital resources. Power plant operators, distributors, and dispatchers control power plants and the flow of electricity from plants to substations, which distribute electricity to businesses, homes, and factories. Electricity is generated from many sources, including coal, gas, nuclear energy, hydroelectric energy (from water sources), and wind and solar power.
The following are types of power plant operators, distributors, and dispatchers:
Nuclear power reactor operators control nuclear reactors. They adjust control rods, which affect how much electricity a reactor generates. They monitor reactors, turbines, generators, and cooling systems, adjusting controls as necessary. Operators also start and stop equipment and record the data. They may need to respond to abnormalities, determine the cause, and take corrective action.
Power distributors and dispatchers, also known as systems operators, control the flow of electricity as it travels from generating stations to substations and users over a network of transmission and distribution lines. They prepare and issue switching orders to route electrical currents around areas that need maintenance or repair. Distributors and dispatchers also monitor and operate current converters, voltage transformers, and circuit breakers. They must detect and respond to emergencies, such as transformer or transmission line failures.
Power plant operators control, operate, and maintain machinery to generate electric power. They use control boards to distribute power among generators and regulate the output from several generators. They regulate the flow of power between generating stations and substations, and they monitor instruments to maintain voltage and electricity flows from the plant.
Social and human service assistants help people get through difficult times or get additional support. They help other workers, such as social workers, and they help clients find benefits or community services.
Social and human service assistants typically do the following:
Social and human service assistants have many job titles, including case work aide, clinical social work aide, family service assistant, social work assistant, addictions counselor assistant, and human service worker. They serve diverse populations with a range of problems. Their work varies, depending on the clients they serve.
With children and families, social and human service assistants ensure that children live in safe homes. They help parents get the resources, such as food stamps or childcare, they need to care for their children.
With the elderly, workers help clients stay in their own homes and under their own care whenever possible. They coordinate meal deliveries or find personal care aides to help older people with day-to-day needs, such as doing errands or bathing. In some cases, human service workers help look for residential care facilities, such as nursing homes.
For people with disabilities, social and human service assistants help find rehabilitation services that aid their clients. They may work with employers to adapt positions to make them accessible to people with disabilities. Some workers find personal care services to help clients with daily living activities, such as bathing or making meals.
For people with addictions, human service assistants find rehabilitation centers that meet their clients' needs. They also find support groups or twelve-step programs. They work with people who are dependent on alcohol, drugs, gambling, or other substances or behaviors.
With veterans, assistants help people discharged from the military adjust to civilian life. They help with practical needs, such as finding housing and applying skills gained in the military to civilian jobs. They also help with navigating the overwhelming number of services available to veterans.
For people with mental illnesses, social and human service assistants help clients find resources to cope with their illness. They find self-help and support groups to provide their clients with an assistance network. In addition, they help those with more severe mental illnesses care for themselves by finding personal care services or group housing.
With immigrants, workers help clients adjust to living in a new country. They help clients locate jobs and housing. They also may help clients find programs that teach English, or they may find legal assistance to help immigrants get their paperwork in order.
With former prison inmates, human service assistants help clients re-enter society by finding job training or placement programs. Human service assistants help former inmates find housing and connect with programs that help them make a new life for themselves.
With homeless people, assistants help clients meet their basic needs. They find temporary or permanent housing. They find places, such as soup kitchens, that provide meals. Human service assistants also help homeless people find facilities for other problems they may have, such as joblessness.
Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.
Roofers typically do the following:
Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.
There are two basic types of roofs, low-slope and steep-slope:
A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.