First fix and second fix

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First fix and second fix are terms used in the UK and Irish housebuilding and commercial building construction industry.

First fix comprises all the work needed to take a building from foundation to putting plaster on the internal walls. This includes constructing walls, floors and ceilings, and inserting cables for electrical supply and pipes for water supply.

Some argue that First Fix starts after the shell of the building is complete, and ends when the walls are plastered. Here is a list, in no particular order, of the elements of First Fix.

The list is not exhaustive.

Second fix comprises all the work after the plastering of a finished house. Electrical fixtures are connected to the cables, sinks and baths connected to the pipes, and doors fitted into doorframes. Second fix work requires a neater finish than first fix.

The division of work is a convenient description because electricians, plumbers and carpenters will probably have to make two separate visits to one property under construction, at separate times. Project managers can report "first fix complete" or "second fix 50% done" and others can understand.

Some construction companies specialise in first fix work or second fix work, but most do both.

In North America, terms such as roughing in and finishing or rough-in and finish work are often heard, referring to similar concepts. Another related set of terms is outside work and inside work (the building is closed to the weather when the latter occurs). Carpenters speak of rough work and trim work (or framing versus trimming), and other fields have analogues, such as machining (roughing versus finishing cuts) and communications (rough draft versus revised draft).

Electrical installations and "third fixes"

Electrical installations can be further divided into first, second and third fixes: [1]

As modern society's reliance on technology increases, the need to properly house sensitive electronic equipment becomes a greater concern. The installation of this equipment takes place in the "third fix" segment of a construction project. It is especially important that installation of sensitive electronic equipment be installed only when a construction site is dust-controlled and prepared for what would be considered "dust free" conditions. For example, for the modern computer server room, equipment would be installed only when dust and atmospheric conditions are minimized and controlled. Similar to the atmospheric needs of medical and scientific research laboratories, the production of discrete semiconductor devices and integrated circuits is undertaken in a cleanroom atmosphere where low levels of environmental pollutants such as particulates and airborne microbes are strictly minimised and most preferably eliminated. [2]

The UK national building specifications, British Standard 5295:1989, specifically addresses "clean room" environments serving electronics manufacturers, as well as the pharmaceutical industry (the Pharmaceutical Industry has, for some time, worked to the ISO standard 14644 which is subtly different). Standard 5295:1989 specifically pertains to constructed interior spaces where higher than normal environmental standards must be maintained, in order to control particulate contamination, temperature and humidity. It is only at the third fix stage, when building site conditions are rendered virtually dust free, so as to minimise the introduction, generation and retention of particles which may contaminate equipment serving the electronics and pharmaceuticals manufacturing process, that the build-out of "clean room" spaces can commence. [3]

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<span class="mw-page-title-main">Outside plant</span>

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<span class="mw-page-title-main">Carpentry</span> Skilled trade

Carpentry is a skilled trade and a craft in which the primary work performed is the cutting, shaping and installation of building materials during the construction of buildings, ships, timber bridges, concrete formwork, etc. Carpenters traditionally worked with natural wood and did rougher work such as framing, but today many other materials are also used and sometimes the finer trades of cabinetmaking and furniture building are considered carpentry. In the United States, 98.5% of carpenters are male, and it was the fourth most male-dominated occupation in the country in 1999. In 2006 in the United States, there were about 1.5 million carpentry positions. Carpenters are usually the first tradesmen on a job and the last to leave. Carpenters normally framed post-and-beam buildings until the end of the 19th century; now this old-fashioned carpentry is called timber framing. Carpenters learn this trade by being employed through an apprenticeship training—normally four years—and qualify by successfully completing that country's competence test in places such as the United Kingdom, the United States, Canada, Switzerland, Australia and South Africa. It is also common that the skill can be learned by gaining work experience other than a formal training program, which may be the case in many places.

<span class="mw-page-title-main">Electrician</span> Tradesperson specializing in electrical wiring

An electrician is a tradesperson specializing in electrical wiring of buildings, transmission lines, stationary machines, and related equipment. Electricians may be employed in the installation of new electrical components or the maintenance and repair of existing electrical infrastructure. Electricians may also specialize in wiring ships, airplanes, and other mobile platforms, as well as data and cable lines.

<span class="mw-page-title-main">Cleanroom</span> Dust-free room for research or production

A cleanroom or clean room is an engineered space, which maintains a very low concentration of airborne particulates. It is well isolated, well-controlled from contamination, and actively cleansed. Such rooms are commonly needed for scientific research, and in industrial production for all nanoscale processes, such as semiconductor manufacturing. A cleanroom is designed to keep everything from dust, to airborne organisms, or vaporised particles, away from it, and so from whatever material is being handled inside it.

<span class="mw-page-title-main">Electrical wiring</span> Electrical installation of cabling

Electrical wiring is an electrical installation of cabling and associated devices such as switches, distribution boards, sockets, and light fittings in a structure.

Electrical wiring in the United Kingdom is commonly understood to be an electrical installation for operation by end users within domestic, commercial, industrial, and other buildings, and also in special installations and locations, such as marinas or caravan parks. It does not normally cover the transmission or distribution of electricity to them.

<span class="mw-page-title-main">Air filter</span> Device composed of fibrous or porous materials which removes solid particulates from the air

A particulate air filter is a device composed of fibrous, or porous materials which removes solid particulates such as dust, pollen, mold, and bacteria from the air. Filters containing an adsorbent or catalyst such as charcoal (carbon) may also remove odors and gaseous pollutants such as volatile organic compounds or ozone. Air filters are used in applications where air quality is important, notably in building ventilation systems and in engines.

<span class="mw-page-title-main">Dropped ceiling</span> Secondary ceiling hung below a main ceiling

A dropped ceiling is a secondary ceiling, hung below the main (structural) ceiling. It may also be referred to as a drop ceiling, T-bar ceiling, false ceiling, suspended ceiling, grid ceiling, drop in ceiling, drop out ceiling, or ceiling tiles and is a staple of modern construction and architecture in both residential and commercial applications.

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In electrical and safety engineering, hazardous locations are places where fire or explosion hazards may exist. Sources of such hazards include gases, vapors, dust, fibers, and flyings, which are combustible or flammable. Electrical equipment installed in such locations can provide an ignition source, due to electrical arcing, or high temperatures. Standards and regulations exist to identify such locations, classify the hazards, and design equipment for safe use in such locations.

ISO 13567 is an international computer-aided design (CAD) layer standard.

<span class="mw-page-title-main">Raised floor</span> Elevated floor above a solid substrate to create a void for mechanical and electrical services

A raised floor provides an elevated structural floor above a solid substrate to create a hidden void for the passage of mechanical and electrical services. Raised floors are widely used in modern office buildings, and in specialized areas such as command centers, Information technology data centers and computer rooms, where there is a requirement to route mechanical services and cables, wiring, and electrical supply. Such flooring can be installed at varying heights from 2 inches (51 mm) to heights above 4 feet (1.2 m) to suit services that may be accommodated beneath. Additional structural support and lighting are often provided when a floor is raised enough for a person to crawl or even walk beneath.

<span class="mw-page-title-main">Underfloor heating</span> Form of central heating and cooling

Underfloor heating and cooling is a form of central heating and cooling that achieves indoor climate control for thermal comfort using hydronic or electrical heating elements embedded in a floor. Heating is achieved by conduction, radiation and convection. Use of underfloor heating dates back to the Neoglacial and Neolithic periods.

<span class="mw-page-title-main">Electrical room</span>

An electrical room is a room or space in a building dedicated to electrical equipment. Its size is usually proportional to the size of the building; large buildings may have a main electrical room and subsidiary electrical rooms. Electrical equipment may be for power distribution equipment, or for communications equipment.

<span class="mw-page-title-main">Server room</span> Room containing computer servers

A server room is a room, usually air-conditioned, devoted to the continuous operation of computer servers. An entire building or station devoted to this purpose is a data center.

<span class="mw-page-title-main">Contamination control</span> Activities aiming to reduce contamination

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<span class="mw-page-title-main">Mechanical systems drawing</span>

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<span class="mw-page-title-main">Central vacuum cleaner</span> Type of vacuum cleaner appliance

A central vacuum cleaner is a type of vacuum cleaner appliance installed into a building as a semi-permanent fixture. Central vacuum systems are designed to remove dirt and debris from homes and buildings, sending dirt particles through piping installed inside the walls to a collection container in a remote utility space. The power unit is a permanent fixture, usually installed in a basement, garage, or storage room, along with the collection container. Inlets are installed in walls throughout the building that attach to power hoses and other central vacuum accessories to remove dust, particles, and small debris from interior rooms. Most power hoses have a power switch located on the handle.

<span class="mw-page-title-main">Roxtec</span> Swedish manufacturing company

Roxtec is a company specialising in the development and manufacture of cable and pipe seals. Roxtec's products are designed to seal cable and pipe penetrations in order to protect from multiple hazards including fire, water, gas, dust, vibrations, electro-magnetic disturbances, vermin, and the risk of explosion. Markets include power, marine, oil and gas, telecoms, infrastructure, industrial equipment, and the process industries.

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References

  1. Russell, Jack (2007). The Streetwise Subbie: How to Survive the Contracts Jungle. 3rd ed. Oxford: Newnes. ISBN   978-0-7506-8061-5. App. 4
  2. Tweney, Dylan; Snyder, Jonathan (October 19, 2010). "A Chip Is Born:Inside a State-of-the-Art Clean Room". Wired.
  3. "Industrial Committee Practice Note 5, Reevaluation 2005, Valuation of Subjects Containing Clean Rooms" (PDF). Scottish Assessors Association. 2005.