Mortgage guide

Development finance for self build

Development finance for self build is a specialist funding route used where a borrower does not meet residential affordability criteria, or where the intended exit is sale or cash repayment rather than long-term mortgage lending. It is fundamentally different from a self-build mortgage and is underwritten on project viability and exit strategy, not personal income.

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Development finance for self build

Development finance for self build is a specialist funding route used where a borrower does not meet residential affordability criteria, or where the intended exit is sale or cash repayment rather than long-term mortgage lending. It is fundamentally different from a self-build mortgage and is underwritten on project viability and exit strategy, not personal income.

Suitable where residential affordability is insufficient

Unlike self-build mortgages, development finance does not rely on income multiples or residential affordability stress testing. Instead, lenders assess the scheme based on build costs, gross development value (GDV), and the credibility of the exit. This makes it suitable for borrowers who are asset-rich but income-light, or whose income structure is incompatible with residential lending.

Designed for sale or cash exits

Development finance is commonly used where the completed property will be sold, refinanced onto a buy-to-let mortgage, or repaid using other capital. There is no requirement for the loan to convert into a residential mortgage on completion, which removes a key constraint present in self-build lending.

Higher leverage against build costs and GDV

Development lenders typically advance funds based on a combination of loan-to-cost (LTC) and loan-to-gross-development-value (LTGDV). Funding of up to 65%-75% of GDV is common, with build costs often funded at a higher percentage than under self-build mortgage structures, subject to risk profile and exit strength.

Stage-released funding with commercial controls

Funds are released in tranches against verified build progress, with monitoring surveyors signing off each stage. Lenders apply commercial-style controls including interest roll-up, retained contingencies, and fixed build cost oversight, reflecting the higher risk profile compared to residential lending.

Pricing and term structure

Development finance is short-term by design, typically running for 6-24 months. Pricing is higher than residential self-build mortgages and is usually quoted monthly rather than annually. Interest is often rolled up and repaid at exit, reducing cashflow pressure during construction.

Appropriate for complex or higher-risk schemes

Development finance can accommodate projects that fall outside residential lender appetite, including non-standard construction, significant structural works, change-of-use schemes, or properties that are uninhabitable at outset.

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Indicative estimate only, based on the figures you enter and the ceilings shown. Lenders also assess experience, planning, the build contract and the exit. This is not an offer of finance. Your property may be repossessed if you do not keep up repayments on a loan secured on it.

Self build mortgage criteria

For context, these are the wider product terms covered by this guide. Availability and eligibility depend on your circumstances and the lender.

Self build mortgage criteria
CriteriaDetail
Loan to Value (LTV)Varies by lender, assessed against the land value and the projected completed value
Build costs fundedVaries by lender and case, released in stages against build progress
TermSet by the lender, subject to age and affordability
Repayment typeInterest only or repayment
Product optionsFixed, variable or base rate tracker, depending on the lender
Barn conversionsYes, with lenders that accept conversion projects

About the author

Joseph Lane CeMAP is an expert development finance broker

Founder, CEO

Calls and emails here go to Joseph personally, not to a general inbox.

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+44 7487 829005joe@mortgagelane.comMore about Joseph

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Frequently asked questions

Is development finance better than bridging for a self-build?

Development finance suits larger or multi-unit schemes built for sale, while a self-build mortgage suits one home to live in. A bridge fills gaps in either, such as securing land before the main finance is approved.

Can you get a self build mortgage on a part-built development?

Some lenders will consider self build mortgages on part-built properties, but the criteria are stricter. Lenders assess the existing works, professional certification, remaining costs and valuation risk before agreeing to fund a partially completed build.

What is build to rent development finance?

Build to rent development finance funds the construction of homes designed to be held and let as a single professionally managed block or single-family rental estate, instead of being sold unit by unit. The facility is repaid by a refinance against the stabilised rent or by a sale to an institutional investor, and on the cases we arrange the build is funded on the residential development ceilings.

How long does build to rent development finance take to arrange?

How long build to rent development finance takes to arrange depends on the scheme. The timeline from a complete rental appraisal to first drawdown is driven by the investment valuation, the monitoring surveyor's review, legal work on any forward-funding or sale agreement and, for a higher-risk block, the Building Safety Regulator's approval. Forward-funding negotiations can take longer, and an adviser sets out the timetable once the package is complete.

Can a business get development finance to build its own premises?

A business can get commercial development finance to build or convert its own premises, assessed on the asset's value and on the business's accounts and the debt service coverage of the stressed annual payment that the exit lender requires. The completed building refinances onto an owner-occupier commercial mortgage serviced from trading.

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