Second fix

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.

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).

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