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Acorn Mortgage Desk · Self-Build & Custom Build Finance

Turn Blueprint Plans Into Reality with Stage-Funded Self-Build Mortgages

Fund plot acquisition and up to 85%–90% of construction costs. Choose between traditional arrears drawdowns or advance stage payments to protect cashflow before materials are purchased.

Four pillars of self-build financing

Cashflow security

Arrears vs. Advance Stage Payments

Compare traditional valuation-arrears payments, released after RICS inspections, with advance funding released before each stage.

Day-one land purchases

Plot Acquisition & Outline Planning

Secure indicative plot funding with acceptable planning, or use unencumbered land as equity for working capital.

Timber frame & ICF

Modern Methods of Construction (MMC)

Specialist underwriting for eco-builds, Passivhaus, modular homes and systems requiring manufacturer deposits.

Refinance or retain

Flexible End-State Conversions

Move the completed build onto a residential or Buy-to-Let mortgage, subject to completion certification and product terms.

Self-Build Cashflow & Stage Drawdown Calculator

A. Land & construction costs

£250,000
£50,000£1,000,000
£450,000
£100,000£2,000,000
£950,000
£250,000£4,000,000
£150,000
£20,000£500,000

B. Funding structure

Indicative illustration only. Facility limit is the lower of 85% of total cost or 75% of GDV. Actual stage releases follow lender valuation and cashflow rules.

Total project cost

£700,000

Maximum self-build facility

£595,000

Six-stage drawdown schedule

Stage 1 · Land purchase & site preparation£148,750
Stage 2 · Foundations & substructure£89,250
Stage 3 · Wallplate / eaves level£89,250
Stage 4 · Wind & watertight enclosure£119,000
Stage 5 · First & second fix£113,050
Stage 6 · Completion & final retention£35,700

Cashflow Insight

Advance stage funding releases funds at the start of each phase, reducing reliance on short-term bridging or expensive overdrafts during construction.

Download Your Self-Build Cashflow & Drawdown Schedule (PDF)

Create a bank-ready six-page dossier with stage payments, contingency planning and structural warranty requirements.

Send these figures straight to a specialist broker — no need to re-enter your numbers.

Apply with These Figures

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Important Regulatory & Structural Warranty Notice

Acorn.mortgage (Trading style of Paul Thompson) is authorised and regulated by the Financial Conduct Authority (FCA #660207). YOUR HOME MAY BE REPOSSESSED IF YOU DO NOT KEEP UP REPAYMENTS ON YOUR MORTGAGE OR ANY OTHER DEBT SECURED ON IT. Self-build mortgage advances are subject to stage valuations by independent RICS surveyors and building control approval. Lenders require an acceptable 10-year structural warranty (e.g. NHBC, Zone, Checkmate) or Professional Consultant’s Certificate (PCC) before final retention release.