Duplex build for a builder-owner

The situation

This is an anonymised composite reflecting a recurring pattern, not a specific settled transaction. A licensed builder with an established trades business decides to build a duplex on a site they own, acting as their own builder rather than engaging an external contractor, intending to sell one dwelling and retain the other as an investment.

Why it's hard

Lenders generally require a fixed-price building contract between an independent developer and a licensed builder as part of assessing construction risk, and a builder-owner acting as their own contractor removes that independent check, which some lenders treat cautiously even where the builder is genuinely well qualified and experienced.

How it can be structured

A construction facility structured with the builder-owner's business as the named contractor under a documented, arm's-length-style building contract, even where the same individual ultimately controls both sides, is the standard approach, with an independent quantity surveyor engaged specifically to verify progress claims given the lack of a genuinely independent contracting party; the exit is the sale of one dwelling and retention of the other as security or an investment asset. Lenders will typically want to see the builder's licensing, insurance and trading history as a business in its own right, separate from this specific project, to establish genuine capability rather than relying solely on the individual's trade qualification. Where the retained dwelling will support the borrower's ongoing serviceability as a rental, that income can be factored into the overall assessment once the project completes.

Because the builder and the borrower are effectively the same party in this structure, some lenders will also require a separate, licensed building supervisor or an external project manager to sign off on progress claims alongside the quantity surveyor, adding a further layer of independent verification beyond what a standard construction facility would require. Insurance is scrutinised particularly closely in this scenario, since the builder's own home warranty and public liability cover need to extend genuinely to a project they own an interest in, which not every standard trades insurance policy automatically covers without a specific endorsement. Where the retained dwelling is intended as the builder's own future residence rather than an investment, the lender will also want clarity on how that changes the eventual serviceability calculation, since owner-occupied intent is assessed differently to a straightforward rental holding. A clear, itemised cost breakdown separating labour the builder is contributing directly from materials and subcontracted trades helps the quantity surveyor verify progress claims accurately throughout the build.

What it typically costs

Pricing reflects the additional independent verification required given the builder-owner structure, generally modestly above a standard construction facility with a fully independent builder, quoted on enquiry once a lender has reviewed the builder's credentials and the project feasibility. Costs include standard construction finance fees alongside the quantity surveyor's independent verification role.

Timeline

1. Same day — scoping call confirming the builder's licensing, business history and the project plan.
2. 5–10 business days — feasibility and building contract documentation, including QS engagement.
3. 3–5 business days — lender matching and submission.
4. 10–15 business days — credit approval and offer.
5. 5–10 business days — documentation and first drawdown.

Questions we'd ask you

1. What is your builder's licence history, and how long has your trades business been operating?
2. Will the retained dwelling be sold, rented, or used as your own residence once complete?
3. What insurance does your building business carry for a project of this kind?
4. Have you engaged an independent quantity surveyor to verify progress claims?
5. What is your plan for the sale proceeds from the dwelling you intend to sell?

Related

Construction finance · Builders & trades · Property developers · QS report