New construction first and second fixes

New construction first and second fixes across London

First fix and second fix are terms used in the UK for 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 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.

• Drain runs: must be downhill and straight
• Spare conduits: draw strings
• Soil pipes
• Copper pipes
• MVHR (mechanical heat recovery ventilation runs)
• Push-fit or other plastic piping
• Electrical back boxes
• Electricity cable runs
• Telephone, data and audiovisual cables
• Socket location
• Security
• Fire alarm
• Normal pipes
• Door bell
• Door frames
• Pocket doorframes
• Stair well: floating / cantilevered?
• Sound insulation
• Plasterboarding

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 door frames. 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.