The nineteenth century: Industrial Revolution

The industrial revolution was manifested in new kinds of transportation installations, such as railways, canals and macadam roads. These required large amounts of investment. New construction devices included steam engines, machine tools, explosives and optical surveying. The steam engine combined with two other technologies which blossomed in the nineteenth century, the circular saw and machine cut nails, lead to the use of balloon framing and the decline of traditional timber framing.

As steel was mass-produced from the mid-19th century, it was used, in form of I-beams and reinforced concrete. Glass panes also went into mass production, and changed from luxury to every man's property.

Plumbing appeared, and gave common access to drinking water and sewage collection.

Building codes have been applied since the 19th century, with special respect to fire safety.

 

The twentieth century

With the Second Industrial Revolution in the early 20th century, elevators and cranes made high rise buildings and skyscrapers possible, while heavy equipment and power tools decreased the workforce needed. Other new technologies were prefabrication and computer-aided design.

Trade unions were formed to protect construction workers' interests. Personal protective equipment such as hard hats and earmuffs also came into use.

From the 20th century, governmental construction projects were used as a part of macroeconomic stimulation policies, especially during the Great depression (see New Deal). For economy of scale, whole suburbs, towns and cities, including infrastructure, are often planned and constructed within the same project (called megaproject if the cost exceeds US$1 billion), such as Brasília in Brazil, and the Million Programme in Sweden.

In the end of the 20th century, ecology, energy conservation and sustainable development have become more important issues of construction.

 

What is construction?

Construction is the process of constructing a building or infrastructure. Construction differs from manufacturing in that manufacturing typically involves mass production of similar items without a designated purchaser, while construction typically takes place on location for a known client. Construction as an industry comprises six to nine percent of the gross domestic product of developed countries. Construction starts with planning, design, and financing; and continues until the project is built and ready for use.

Large-scale construction requires collaboration across multiple disciplines. A project manager normally manages the job, and a construction manager, design engineer, construction engineer or architect supervises it. Those involved with the design and execution must consider zoning requirements, environmental impact of the job, scheduling, budgeting, construction-site safety, availability and transportation of building materials, logistics, inconvenience to the public caused by construction delays and bidding. Large construction projects are sometimes referred to as megaprojects.

 

Types of construction

In general, there are three sectors of construction: buildings, infrastructure and industrial. Building construction is usually further divided into residential and non-residential (commercial/institutional). Infrastructure is often called heavy civil or heavy engineering that includes large public works, dams, bridges, highways, railways, water or wastewater and utility distribution. Industrial construction includes refineries, process chemical, power generation, mills and manufacturing plants. There are also other ways to break the industry into sectors or markets.

Engineering News-Record (ENR), a trade magazine for the construction industry, each year compiles and reports data about the size of design and construction companies. In 2014, ENR compiled the data in nine market segments divided as transportation, petroleum, buildings, power, industrial, water, manufacturing, sewer/waste, telecom, hazardous waste and a tenth category for other projects. In their reporting, they used data on transportation, sewer, hazardous waste and water to rank firms as heavy contractors.

The Standard Industrial Classification and the newer North American Industry Classification System have a classification system for companies that perform or engage in construction. To recognize the differences of companies in this sector, it is divided into three subsectors: building construction, heavy and civil engineering construction, and specialty trade contractors. There are also categories for construction service firms (e.g., engineering, architecture) and construction managers (firms engaged in managing construction projects without assuming direct financial responsibility for completion of the construction project).

Building construction is the process of adding structure to real property or construction of buildings. The majority of building construction jobs are small renovations, such as addition of a room, or renovation of a bathroom. Often, the owner of the property acts as laborer, paymaster, and design team for the entire project. Although building construction projects consist of common elements such as design, financial, estimating and legal considerations, projects of varying sizes may reach undesirable end results, such as structural collapse, cost overruns, and/or litigation. For this reason, those with experience in the field make detailed plans and maintain careful oversight during the project to ensure a positive outcome.

Commercial building construction is procured privately or publicly utilizing various delivery methodologies, including cost estimating, hard bid, negotiated price, traditional, management contracting, construction management-at-risk, design & build and design-build bridging.

Residential construction practices, technologies, and resources must conform to local building authority regulations and codes of practice. Materials readily available in the area generally dictate the construction materials used (e.g. brick versus stone, versus timber). Cost of construction on a per square meter (or per square foot) basis for houses can vary dramatically based on site conditions, local regulations, economies of scale (custom designed homes are often more expensive to build) and the availability of skilled tradespeople. Residential construction as well as other types of construction can generate waste such that planning is required.

According to McKinsey research, productivity growth per worker in construction has lagged behind many other industries across different countries including in the United States and in European countries. In the United States, construction productivity per worker has declined by half since the 1960s.

The most popular method of residential construction in North America is wood-framed construction. Typical construction steps for a single-family or small multi-family house are:

· Obtain an engineered soil test of lot where construction is planned           

· Develop floor plans and obtain a materials list for estimations (more recently performed with estimating software)                       

· Obtain structural engineered plans for foundation (soil test report obtained earlier will be used by engineer to design foundation), floor plan, floor (if two story).                            

· Obtain lot survey

· Obtain government building approval if necessary                   

· If required obtain approval from HOA (homeowners association) or ARC (architectural review committee)                                      

· Clear the building site (demolition of existing home if necessary)               

· Survey to stake out for the foundation

· Excavate the foundation and dig footers (Scope of work is dependent of foundation designed by engineer)

· Install plumbing grounds                                          

· Pour a foundation and footers with concrete                         

· Build the main load-bearing structure out of thick pieces of wood and possibly metal I-beams for large spans with few supports. See framing (construction)

· Add floor and ceiling joists and install subfloor panels

· Cover outer walls and roof in OSB or plywood and a water-resistive barrier.

· Install roof shingles or other covering for flat roof

· Cover the walls with siding, typically vinyl, wood, or brick veneer but possibly stone or other materials

· Install windows                                               

· Frame interior walls with wooden 2x4s

· Add internal plumbing, HVAC, electrical, and natural gas utilities

· Building inspector visits if necessary to approve utilities and framing

· Install insulation and interior drywall panels (cementboard for wet areas) and to complete walls and ceilings

· Install bathroom fixtures                                                    

· Spackle, prime, and paint interior walls and ceilings

· Additional tiling on top of cementboard for wet areas, such as the bathroom and kitchen backsplash

· Installation of final floor covering, such as floor tile, carpet, or wood flooring

· Installation of major appliances                                                        

· Unless the original owners are building the house, at this point it is typically sold or rented.

 

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