Hawktress Field Notes

Written on the tools.
Not from a desk.

Methodology, field notes and operator handbooks from the BuildHawk team and the Hawktress platform. Written by people who run estimating and contract administration on live Australian residential jobs.

Methodology6 May 20264 min read

The 5% Variance Rule: zero tolerance starts at contract

Every estimate carries uncertainty. The question is not whether variance exists, it is whether the builder controls it or absorbs it. Up to 5% per line item is acceptable at estimate stage. At contract execution, the tolerance is zero.

By Nathan Holloway · Founder · BuildHawk and Hawktress

Methodology6 May 2026

Variations are where margin dies

Most builders do not lose their margin on the estimate. They lose it after the contract is signed, in the space between what was agreed and what actually gets built. One poorly managed variation register can wipe 8 to 12 points off margin before the roof is on.

By Nathan Holloway · 4 min read

Operator Handbook6 May 2026

The geo-report gap: why sitework eats margin between bore holes

A geotechnical report tells you what is at three or four points on the site. Builders who price sitework as a locked sum are pricing those points as though they represent the entire allotment. The gap between bore holes is where margin disappears.

By Nathan Holloway · 5 min read

Video
Founder4 May 2026

Hawktress: Cost Data That Actually Matters

The cost data that actually matters in construction has never lived in a software platform. It lives in completed jobs. Hawktress is an attempt to fix that.

By Nathan Holloway · 5 min read

Video
Operator Handbook4 May 2026

Variation Control: The System That Removes Discretion

A builder can price a job accurately, manage trades well, and still finish in the red. In most cases, the cause is the same: variations that were completed but never properly controlled.

By Nathan Holloway · 5 min read

Video
Methodology4 Feb 2026

Reading the Monthly Director Report: A Walkthrough

Every active job, every committed cost, every flagged variation, every dollar of cash position, in one report by the 5th of the month. Here is how to read it in 90 seconds and what to act on first.

By Nathan Holloway · 8 min read

Video
Operator Handbook8 Oct 2024

Why every builder underprices sitework in a new region

Excavation, drainage, retaining and site clean. Together they are usually 4 to 7% of the contract. Builders almost universally get them wrong on the first job in a new region. Here is what to actually budget.

By Nathan Holloway · 6 min read