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What’s the difference between a first and second fix?

There are two main stages to most building projects: the "first fix" and the "second fix". Do you know what these terms mean?

2 min read

If you’re planning any kind of house extension or loft conversion, you’ve probably heard someone using the terms "first fix" and "second fix", but what do they mean?

All home extensions start with a set of awesome architectural floor plans, and either a planning application or lawful development certificate application. But once you’ve actually started construction, you can think of the “first fix” and “second fix” as the two main stages of your building project.

It’s important to know the difference between these two stages, as it’s likely that individual contractors - including plumbers and electricians - will need to come back to finish different jobs during each fix.

The first fix

This is everything that happens between laying down your foundations and finishing your plastering.

It will probably include constructing floors, ceilings and walls, inserting electrical cables and adding pipes for your water supply.

Depending on your home extension or loft conversion, it might also include installation of:

  • Telephone wires
  • Security systems
  • Fire alarms
  • Door bells
  • Sound insulation
  • Pocket door frames
  • Stairs and stairwells

Before you begin construction, make sure you have a set of detailed plans, a clear, itemised contract, and a good understanding of who exactly is responsible for what.

You might even decide to hire a project manager to make sure everything is kept under control.

The second fix

This refers to everything that comes after plastering has finished.

It might include:

  • Connecting up electrical fixtures
  • Adding in sinks and baths
  • Fitting doors into door frames

As the second fix is closer to the end of the project, it requires a closer attention to detail and a neater finish than most of the first fix work, so pay close attention.

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