How to Avoid Underquoting on Building Jobs
Builders underquote when a priced tender or quote comes in below what the job will actually cost to deliver — usually because of missed scope items, out-of-date rates, forgotten wastage and preliminaries, or a margin too thin to absorb the surprises that turn up on site. It matters because winning unprofitable work is worse than not winning the job at all: it ties up cash, crew and equipment in a project that erodes profit instead of building it. Avoiding it comes down to a disciplined takeoff, current rates, an honest allowance for contingency, a deliberate margin, and a habit of checking what jobs actually cost against what was quoted.
Key takeaways
- Underquoting means the price is lower than the true cost of delivering the job — it is dangerous because winning unprofitable work damages cash flow and profit more than not winning the job at all.
- The most common causes are missed scope items, out-of-date rates, forgotten wastage, omitted preliminaries and on-costs, no contingency, thin or no margin, optimism bias, and a rushed takeoff.
- A clear scope of works with exclusions stated explicitly in writing stops the gaps between trades and between the quote and the drawings that cause items to go unpriced.
- Contingency and margin cover different things — contingency covers the unexpected, margin covers overheads and profit — and neither should be cut to compensate for a weak cost base.
- Comparing quoted cost to actual cost, trade by trade, on every won and lost job is one of the most reliable ways to catch a pattern of underquoting before it repeats.
Why builders underquote — and why it’s dangerous
Underquoting happens when the price submitted is lower than the true cost of delivering the job — not because a builder chooses to run at a loss, but because something in the pricing process failed to capture the real cost. It rarely happens all at once: a few missed items here, an old rate there, no allowance for the unexpected, and the total quietly slips below cost.
It is dangerous because winning unprofitable work is worse than not winning the job at all. A job priced below cost still consumes real labour, materials, plant and site time — it just does so while losing money, and the loss on one badly quoted job can consume the margin earned on several good ones.
- Cash flow strain, because the job absorbs more labour and material cost than the progress payments ever recover
- Crew, plant and site time tied up on a job that is losing money rather than earning it
- A pattern that compounds — a business that consistently underquotes is often busier and less profitable at the same time
The common causes of underquoting
Underquoting is rarely one single mistake — it is usually two or three of these happening on the same job: missed scope items, out-of-date rates, forgotten wastage, omitted preliminaries and on-costs, no contingency, thin or no margin, optimism bias, and a rushed takeoff.
Each cause under-prices the job differently, which is why a generic fix — like simply adding a bigger margin across the board — rarely solves the problem on its own.
| Common cause | How it under-prices the job | The fix |
|---|---|---|
| Missed scope items | An item on the plans or specification is never measured or priced | Work from a structured Bill of Quantities and check every trade section against the drawings |
| Out-of-date rates | Rates reflect old prices, not current supplier and subcontractor quotes | Review rates regularly and reprice high-value lines before submitting |
| Forgotten wastage | Materials are priced at the exact measured quantity, with nothing for offcuts or breakages | Apply a wastage allowance to every relevant material line |
| Omitted preliminaries and on-costs | Site costs — supervision, facilities, insurances — left out or guessed at | Price preliminaries as their own line items, built up like trade costs |
| No contingency | The quote assumes everything goes to plan, with nothing set aside for the unexpected | Include a contingency sum sized to the job’s risk |
| Thin or no margin | The price barely covers cost, or margin is cut to win the job | Set margin deliberately, based on overheads and risk, not competitive pressure |
| Optimism bias | The estimate assumes best-case duration, crew size or site conditions | Price to a realistic scenario and sense-check against past jobs |
| Rushing the takeoff | Quantities are estimated quickly under time pressure rather than measured properly | Protect time for the takeoff, or use automated measurement |
Missed scope items: why a clear scope and exclusions matter
Missed scope items are one of the most common and costly causes of underquoting, and they are usually a symptom of an unclear scope of works rather than plain carelessness — if what is included and excluded from the price isn’t explicit, something will fall through the gap between trades, or between the quote and the plans.
A clear scope and a written list of exclusions protect the price from both directions: everything genuinely included actually gets measured and costed, and the client can see what is not covered, so an item that surfaces later becomes a variation rather than a cost quietly absorbed.
- State exclusions explicitly in writing — “excludes” is as important a word as “includes”
- Check the scope against every trade section of the drawings and specification, not just the obvious ones
- Flag provisional sums and prime cost items clearly, so they are not mistaken for a fixed, fully priced cost
Out-of-date rates and forgotten wastage
Out-of-date rates under-price a job quietly, because the takeoff and the arithmetic can be entirely correct while the unit prices behind them are simply wrong. A rate carried over from a job priced months ago rarely reflects today’s material and labour costs, particularly during periods of price movement.
Wastage compounds the same problem in materials specifically: a measured quantity describes the finished job, not what actually needs to be bought, and offcuts, breakages and cutting losses mean the real material cost is almost always higher than the measured quantity on its own.
- Reprice high-value material and subcontract lines against current supplier and subbie quotes before submitting
- Apply a wastage allowance appropriate to the material and method — sheet materials, boarding and tiling typically waste more than bulk fill (figures vary by job and are illustrative examples only)
- Keep a rates library that is easy to update, so a stale rate is a five-minute fix rather than a hunt through old jobs
No contingency and thin margin
No contingency and a thin margin under-price a job differently to the causes above — they don’t leave anything out of the measured cost, they simply leave nothing in reserve once that cost is met, so any surprise on site comes straight out of profit, or worse.
Contingency and margin are not the same allowance and shouldn’t be confused. Contingency covers the unexpected, sized to the risk of the job, while margin covers overheads and profit on top of an accurate cost base. Cutting one to protect the other still leaves the job under-priced.
- Size contingency to the actual risk of the job — a well-documented repeat job carries less risk than one with incomplete drawings
- Never treat margin as the buffer for missing scope or stale rates — margin is profit, not a safety net
- Be wary of cutting margin to win a tender without also reassessing the job’s risk
A practical checklist to catch underquoting before you submit
A short, consistent checklist run before every tender or quote goes out catches most of the common causes of underquoting, because it forces a deliberate review of scope, rates, wastage, preliminaries, contingency and margin rather than relying on memory under deadline pressure.
Anti-underquoting checklist
Before you submit: (1) Scope matched line-by-line to the drawings and specification. (2) Exclusions stated in writing. (3) Rates checked against current quotes. (4) Wastage applied to every relevant material. (5) Preliminaries priced as their own line items. (6) A contingency sum sized to the job’s risk. (7) Margin set deliberately, not cut to meet a number. (8) The final price sense-checked against similar past jobs.
Reviewing won and lost jobs to catch the pattern
Reviewing won and lost jobs after the fact is one of the most reliable ways to catch underquoting, because a single job can look like bad luck while a pattern across several jobs almost always points back to the same one or two causes.
The comparison that matters most is quoted price against actual final cost, trade by trade — it shows exactly where the estimate diverged from reality, whether that is a rate, a wastage allowance, a missed scope item or a preliminaries figure, so the same mistake isn’t repeated on the next job.
- Compare quoted cost to actual cost by trade section, not just at the bottom line
- Look at jobs won on price against jobs lost on price — both tell you something about where your numbers sit
- Feed what is learned back into the rates library and the takeoff process, not just the next quote
How My Trade Hub helps you avoid underquoting
My Trade Hub helps you avoid underquoting by tightening the three places it most often starts: the takeoff, the rates, and the visibility of the finished price. Automated quantity takeoff measures items directly from your uploaded plans, so scope items are less likely to go unpriced because a page was skimmed under time pressure.
An editable rates library keeps your own labour, material and plant rates current and applies them automatically to measured quantities, so a stale rate is a quick edit rather than a hidden cost sitting in every quote. Because the Bill of Quantities is structured line by line, gaps in scope, preliminaries or contingency are visible before the tender goes out, not after the job is won — all as part of an estimating workflow that runs 60-75% faster than doing it manually. It’s free to create a My Trade Hub account; estimating, takeoff and tender preparation sit on the paid Starter, Scale and Professional plans in AUD, with no lock-in contracts.
Frequently asked questions
Why do builders underquote jobs?
Usually a combination of causes rather than one alone — missed scope items, out-of-date rates, forgotten wastage, omitted preliminaries, no contingency, a thin or cut margin, optimism about how the job will run, and a takeoff done too quickly.
What is the most common cause of underquoting in construction?
Missed scope items are among the most common single causes, usually because the scope of works and its exclusions were not stated explicitly in writing, letting an item fall through the gap between trades.
How do you avoid underquoting a building job?
Run a consistent checklist before every quote goes out: match the scope to the drawings, state exclusions in writing, check rates are current, apply wastage, price preliminaries as their own line items, include a contingency sized to risk, and set margin deliberately.
What is the difference between contingency and margin?
Contingency is an allowance for the unexpected — things that may or may not happen on the job, sized to its risk and complexity. Margin covers business overheads and profit on top of an accurate cost base. They cover different things, and cutting one to protect the other still leaves the job under-priced.
How much wastage should I allow for materials?
Wastage varies by material and method, so there is no single correct figure — allowances commonly used as a starting point range from around 5% for low-waste bulk materials up to 15-20% for sheet materials or tiling cut to a pattern (illustrative examples only). Adjust for the specific job and check supplier guidance where available.
How do I know if I underquoted a past job?
Compare the quoted cost to the actual final cost, trade by trade. If actual costs consistently exceed the quote in the same sections — commonly materials, labour hours or preliminaries — that pattern points to the specific cause.
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