What is GDV vs GDC in development finance?
Almost every development finance conversation eventually comes back to two figures: Gross Development Value (GDV) and Gross Development Cost (GDC), sometimes referred to as total project cost.
Developers often have an instinctive feel for both numbers (what the finished scheme will be worth, and roughly what it will cost to build), but the way lenders actually use these two figures together to size a facility is less widely understood, and it's the single biggest factor in how much you can actually borrow.
Get this right before you approach a lender, and you'll have a realistic sense of what's fundable before you spend time and money on valuations and legal costs. Get it wrong, and you risk discovering partway through underwriting that your scheme can raise considerably less than you assumed.
What is Gross Development Value (GDV)?
GDV is the estimated market value of your scheme once it's fully built and finished, valued as if it were complete and ready to sell or let on the open market today. It's not what you hope the market will do over the build period, and it's not a figure plucked from a sales brochure. A properly prepared GDV is built from comparable evidence: recent sales of similar finished properties in the same area, adjusted for specification, size and condition.
GDV is assessed under the special assumption that the development is already complete as of the valuation date. It deliberately strips out the uncertainty of the build period itself.
Lenders will instruct their own valuer to independently assess GDV. Your own estimate, however well-researched, is a starting point for discussion, not the figure the facility gets sized against.
GDV typically receives more conservative scrutiny for schemes with a longer build programme, because there's more time for market conditions to change between underwriting and the actual sale or letting.
What is Gross Development Cost (GDC)?
GDC is the total cost of delivering the scheme from where you stand today through to a finished, sellable or lettable product. It's a more comprehensive figure than just the build cost, and developers who understate it by focusing only on construction costs are one of the most common reasons a development appraisal doesn't hold up under a lender's scrutiny. A properly built GDC typically includes:
Land or property purchase cost, including stamp duty and acquisition costs.
Build costs, ideally from a quantity surveyor's cost plan rather than a contractor's estimate alone.
Professional fees, like those for an architect, structural engineer, planning consultant, QS, project manager, and any other consultants needed to deliver the scheme.
Statutory costs, such as planning application fees, building control, and any Section 106 or CIL contributions.
Finance costs, including arrangement fees, interest on the facility across the build period, and exit fees.
Contingency, which is a buffer against cost overruns and unforeseen issues, sized appropriately to the scheme's complexity and risk.
Sales and marketing costs, where the exit is a sale rather than a retained investment.
Lenders will often work with their own monitoring surveyor to test your GDC figure against build cost data and comparable schemes, and a contingency allowance that looks thin for the scheme's complexity is one of the fastest ways to trigger further questions.
How do lenders use GDV and GDC together to size a facility?
Lenders apply two different ratios, one against GDV and one against GDC (total cost), and the final loan is capped at whichever of the two calculations produces the lower number.
To work this out, you can:
Calculate the maximum loan under the Loan-to-GDV ratio. This is typically up to 60% of GDV for senior debt at Mayflower, rising to 70–75% under a stretch senior structure.
Calculate the maximum loan under the Loan-to-Cost ratio. This looks at how much of total project cost (GDC) the lender is prepared to fund, which is often a higher percentage, but applied to a different base figure.
Take the lower of the two results. Whichever ratio produces the smaller loan amount becomes the actual ceiling on what the lender will advance.
Why does it work this way?
Because the two ratios are protecting the lender against different risks. The Loan-to-GDV ratio protects against the finished scheme being worth less than expected, or the market moving against you before you sell or refinance. The Loan-to-Cost ratio protects against the build itself overrunning, or the scheme having so little profit margin built in that small cost increases wipe it out entirely. A lender needs to pass both tests, not just one.
This could look like:
Scenario 1: Low land cost, high profit margin (a well-margined scheme)
Because the land is cheap relative to the finished value, the Loan-to-GDV ratio hits its cap at a relatively low loan amount compared to what the Loan-to-Cost calculation would allow on its own. The GDV ratio is the more restrictive of the two, so it's the one that sets the ceiling on what the lender will advance.
Scenario 2: High land cost, tighter margin
When land cost is high, the scheme's profit margin is squeezed and the cost base becomes a larger proportion of GDV. In this case the Loan-to-Cost cap is reached first — before the GDV ratio would become a constraint. The GDC ratio binds instead.
In practice, well-margined schemes (where the land was bought sensibly and the finished value comfortably exceeds total cost) tend to be capped by the GDV ratio. Tighter-margin schemes, where land cost is a larger share of GDV, tend to be capped by the GDC ratio instead. Understanding which one is likely to bind on your scheme, before you approach a lender, tells you roughly how much you can actually raise.
How does this tie into Mayflower's funding tiers?
The four tiers Mayflower structures development finance facilities across (Senior Debt, Stretch Senior, Mezzanine, and Equity Finance) are really four different answers to the same GDV-and-GDC sizing exercise, layered on top of each other:
Senior Debt: up to 60% of GDV, the most conservative position, sized primarily against the finished value.
Stretch Senior: 70 - 75% of GDV, a single facility taking a larger share of the GDV-based lending, for borrowers and schemes the lender has more confidence in.
Mezzanine Finance: layered on top of senior debt, taking total funding to 85 - 90% of total project cost (GDC), explicitly closing the gap that the GDV-based senior facility leaves.
Equity Finance: funding up to 95 - 100% of cost, for schemes where even the combined senior and mezzanine layers don't reach the funding level required.
Notice how the lower tiers are expressed as a percentage of GDV, and the higher tiers shift the conversation to a percentage of GDC. That happens as the loan moves further up the funding stack; the binding question shifts from ‘what's this worth when it's finished?' to ‘how much of the actual cost are we now covering?' Each additional layer is priced and structured to reflect that shift in risk.
How can you strengthen your numbers before approaching a lender?
Commission an independent GDV assessment early. A RICS-qualified valuer or an experienced local agent who gives you a realistic, evidence-based GDV before you apply avoids surprises once the lender's own valuer is instructed.
Build your GDC from a proper cost plan, not a rough estimate. A quantity surveyor's cost plan, covering build costs, fees, statutory costs and contingency, gives you (and your lender) a defensible figure rather than a guess.
Stress-test your numbers against a lower GDV and a higher GDC. Before you commit to a site, check what happens to your facility size and profit margin if the finished value comes in 5-10% lower than hoped, or costs run 10% over.
Hold a realistic contingency. An unrealistically thin contingency makes your GDC look artificially low, which can flatter your appraisal on paper but will be challenged by a lender's monitoring surveyor.
Understand which ratio is likely to bind on your scheme before you apply. This tells you which figure to focus your evidence and preparation on, and helps set realistic expectations about facility size from the outset.
Work with a broker who can model both ratios against multiple lenders. Lenders vary in how they weight GDV versus GDC, and in where their LTV and LTC caps sit. Matching your scheme to the right lender can materially change the facility size on offer.
Common mistakes to avoid
The most common error we hear of is quoting only one ratio and assuming it determines how much you can raise. Lenders apply both the GDV and GDC ratios and use whichever produces the lower loan amount, so focusing on just one gives a misleading picture of what you can actually borrow.
It's also easy to understate GDC by omitting fees, contingency, or financing costs. A cost figure that only reflects the build contract looks better on paper, but a lender's assessment will adjust for the full picture. Usually reducing the loan size you were expecting as a result.
On the GDV side, the equivalent mistake is using asking prices rather than achieved sales as the basis for your valuation. Lenders value against comparable evidence of actual completed transactions, not aspirational pricing, so an optimistic GDV is likely to be revised downward.
Build programme length is also worth factoring in from the start. A longer programme gives the market more time to move against you, and lenders will often apply more caution to GDV on longer schemes to account for that uncertainty.
Finally, don't treat contingency as optional padding. A thin contingency increases the likelihood of a mid-build funding gap, which is precisely the scenario lenders stress-test against when assessing your application.
Have you got more questions on development finance?
If you want a clearer sense of how much your scheme could realistically raise, it's worth working through the GDV and GDC numbers properly before you approach a lender.Book a free call with Mayflower to talk through your appraisal, or visit our development financepage to see how our Senior Debt, Stretch Senior, Mezzanine and Equity Finance tiers are structured around these figures.
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