What is SFG20?
SFG20 is a library of standard maintenance schedules for building services, widely used in UK facilities management as the reference for what maintenance tasks each asset type requires and at what frequency.
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<img src="https://facilityoptix.co.uk/glossary/sfg20/diagram.svg" alt="SFG20 — diagram from FacilityOptix" width="880" height="620" loading="lazy">
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<a href="https://facilityoptix.co.uk/glossary/sfg20">What is SFG20?</a> — diagram by
<a href="https://facilityoptix.co.uk">FacilityOptix</a>
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</figure>Its value is that it is maintained. Regulations and standards change, and a maintenance regime built from a schedule library that tracks those changes stays current in a way one built from a spreadsheet does not.
Schedules are colour-coded by criticality, separating statutory and mandatory tasks from those that are business-critical or discretionary. That distinction is what allows a budget conversation to happen without putting compliance on the table.
It is a licensed commercial product rather than a public standard, and it is a reference rather than a legal requirement. Using it is the industry norm; being required to use it is not the same thing.
In practice
A contractor quoting against a standard the client has never read.
The specification references a maintenance library. The client assumes that means everything in it, and the contractor has priced the core tasks at the frequencies they judged appropriate.
A standard is a library of task schedules rather than a single answer, and what is included is a commercial decision taken inside it.
Comparing two quotes both claiming compliance requires knowing which schedules and which criticality each assumed.
What goes wrong in practice
- Schedules imported once and never refreshed as the library was updated.
- Applied wholesale without matching schedules to the assets actually present.
- Criticality colour coding ignored, so statutory tasks are deferred alongside discretionary ones.