First fix (sometimes described as shell and first fix ) is a short-hand term used to describe the processes that are undertaken during construction works up to the point of applying internal surfaces – typically plaster. It is normally used in relation to the work of specific trades such as carpenters, plumbers and electricians.
Generally first fix will include constructing the structure, cladding, flooring, doorframes, stairs and so on and installing cables for electrical and ICT distribution, pipework for water and gas distribution and heating ventilating and air-conditioning (HVAC) distribution. First fix is not normally visible when looking at the finished building. Where possible first fix should be tested before second fix (for example plumbing riser stacks).
Second fix takes place after the internal surfaces have been applied. It comprises those items that are visible in a finished area and are held back to avoid damage, or sadly sometimes theft. This may include fitting internal doors, skirting, architraves, handrails, fixtures and fittings, including connection of appliances (such as electrical equipment, sanitaryware, radiators and so on) testing and commissioning.
Typically there will be a change of trades operating on the site, and a break in activity for some trades between first and second fix.
In hotels and residential work there is sometimes a third fix of fixtures and fittings of high value that require fitting or service connections such as chandeliers, white goods, picture-lit artwork and fabrics.
As first fix, second fix and third fix do not have accurate standard definitions, it is very important that contract documentation sets out precisely what work is to be carried out and by who, rather than relying on ambiguous short-hand terms.
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