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ADU change orders: how they should work

By the HyreADU research desk. Last checked .

The short answer

ADU change orders are written changes to the contract’s scope, price or schedule.

In California, a change order becomes part of the contract once it is written and signed by both parties before the work starts, and it must describe the work, the cost added or removed, and the effect on progress payments (Bus. & Prof. Code § 7159). Never approve extra work verbally.

What a change order must show

  • The scope of the extra or changed work.
  • The cost added or subtracted.
  • The effect on the schedule of progress payments.
  • Signatures of both parties before the work starts.

Why change orders happen on ADUs

  • Plan check comments that change the design.
  • Hidden conditions, especially in garage conversions.
  • Site work or utilities missing from the bid.
  • Allowance items chosen above the allowance.
  • Owner changes during the build.

Keeping them under control

  • Finish the design and choose finishes before signing.
  • Ask for itemized bids with site work and utilities as lines.
  • Set realistic allowances.
  • Keep your own contingency.
  • Log every change order with its date and amount.

If change orders pile up, read ADU cost overrun.

What to do next: read the questions to ask an ADU builder, check what decides ADU cost, then tell us about your project. Matching is not live yet, so we reply with information, not a quote.

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Questions

Can a contractor charge for work I did not approve in writing?

California requires change orders in writing and signed before the work. For disputes, get legal advice.

Who pays for plan check changes?

Your contract should say. Ask before signing.

Is a markup on change orders normal?

Many contracts set one. Agree it in advance.

Do allowance overages need a change order?

Put them in writing either way.

Sources

HyreADU is a publisher. It does not design, permit or build ADUs, has no partner builders, and gives no legal, tax or engineering advice. Rules vary by state and city; California rules are labeled as such.