What to include in a building variation

If you'd rather start from a pre-built layout with all seven baked in, grab the free building variation template and fill it in as you read.

1. Reference to the original contract or quote

A variation only means something as a change to something. Name the job, the original quote or contract number, and its date. Without this anchor, the document is just a second quote floating loose — and at dispute time, "which agreement does this vary?" is the first question asked.

2. Scope: what was quoted, what it is now

The single most useful structure is was/now. State what the original scope said, then what it becomes. "Was: standard ceramic floor tiles to bathroom as quoted. Now: large-format porcelain tiles, customer supplied, laid to same area." Two lines, and nobody can later blur the boundary between the original job and the change. Describe the change specifically — quantities, areas, materials — because vague scope is where variation disputes live.

3. The reason for the change

One sentence on why: customer request, hidden condition discovered (rot, asbestos, non-compliant wiring), council or certifier requirement, material unavailability. The reason does quiet work later — a variation caused by "owner requested upgrade" reads very differently in a dispute from one caused by "latent defect found on demolition", and some contracts treat those categories differently for time and cost.

4. Cost breakdown, with GST shown

Break the price into its parts — labour, materials, subcontract, equipment — rather than one bare number. A breakdown looks priced rather than plucked, and it survives the "how did you get to that?" conversation. Then show GST explicitly: subtotal, GST, total including GST. A variation can also be a credit (scope removed); show that as a negative the same way. Never leave "plus GST or including GST?" open to interpretation — that ambiguity alone is a 10% argument.

5. Extension of time

Extra work takes extra days, and if the variation is silent on time, you've quietly agreed to do more work in the same schedule — with liquidated damages or an angry customer waiting if you run over. State the extra working days, even if it's zero ("no change to completion date"). Saying zero on purpose beats saying nothing by accident.

6. The revised contract total

State the arithmetic: original contract sum, plus previously approved variations, plus this variation, equals the new total. This is the line customers actually care about, and showing it every time means the final invoice is never a surprise. It also keeps you honest about how many variations have stacked up — a job that has drifted 20% over contract is something both sides should be seeing in writing as it happens, not discovering at the end.

7. Approval — dated, from the person who pays

A variation without approval is a proposal. Get a signature or clear written acceptance, dated, from the party who is actually liable under the contract — not the tenant, not one half of a couple if both are on the contract, not the site foreman unless they hold that authority. Best practice is approval before the varied work starts; a variation signed after the fact still helps, but you've spent your leverage.

A worked example

Common mistakes

• Describing only the new work. Without the "was", the customer can argue the extra was inside the original scope all along. Was/now closes that door.
• One lump-sum price. A bare "$1,463" invites haggling; a breakdown invites agreement.
• Ignoring time. Every silent variation shortens your real schedule for free.
• No running total. Ten small approved variations still produce one shocking invoice if nobody tracked the revised contract sum.
• Approval from the wrong person, or after the work. Authority and timing are most of what makes approval worth having.
• Assuming a good format satisfies the law. For registered domestic building work, statutory requirements can override anything on this page. Check your state.

Where TradieCue fits

The hard part of variations isn't knowing the format — it's producing the document on the day the change is agreed, while you're mid-job with dirty hands. TradieCue closes that gap: say the change out loud in rough words ("Kelsey St — laundry's getting waterproofed and tiled to match the bathroom, day's labour plus materials, $1,330 plus GST, adds two days") and Timmy drafts a variation on the right job with your figures in it. Prices come from the user and stay editable. Timmy structures the work and wording; it does not invent amounts. Nothing is sent automatically. Every quote, variation and follow-up is a draft the user reviews, edits and shares themselves.

The draft is a starting point in the structure above, fully editable before you share it — and like any generated document it's paperwork help, not legal advice. See variation capture for the feature, how to document extra work for the habits around it, or the building variation template to do it by hand.

Common questions