The capital stack in property development: layers, waterfall and worked example

The short answer

The capital stack is the layered structure of funding behind a property development, ranked by who is repaid first and who carries the most risk. From the bottom it runs senior debt, mezzanine debt, preferred equity and common equity: senior debt is repaid first and costs least, common equity is repaid last and carries the most risk and the most upside. Building an optimal stack means matching each layer to the scheme so the blended cost of capital is as low as the risk allows.

The capital stack is the full set of funding layers behind a development, arranged in order of repayment priority. It is the single most useful lens for understanding how a scheme is financed, because it tells you two things at once: who gets their money back first, and who is taking the most risk for the most reward. Every source of money in a project, from the senior bank loan to the developer's own cash, occupies a defined rung, and its position on that ladder sets both its cost and its risk.

We are a principal mezzanine lender that also arranges the rest of the stack whole of market. This guide sets out how the layers fit together, who is paid in what order, and how to assemble a structure that stands up.

What is the capital stack in property development?

The capital stack is a ranking of every layer of capital funding a scheme, from the safest and lowest-cost at the bottom to the riskiest and highest-cost at the top. It exists because a development is rarely funded by a single source. Senior debt does most of the heavy lifting, but it will not cover the whole cost, so further layers are stacked on top until the total is funded. The order of those layers is not cosmetic: it is a legal hierarchy that dictates who is repaid first when the scheme sells, and who bears the loss if it sells for less than hoped.

Two forces run in opposite directions up the stack. As you climb, the cost of each layer rises, because each one is repaid later and carries more risk. At the same time, the potential return rises, because the layers nearer the top share in the upside. Senior debt is cheap and safe; common equity is expensive to the project and risky, but it keeps everything left over.

The four layers

A full development stack has up to four layers. Not every scheme uses all four, but the order never changes.

Senior debt

Senior debt is the largest and safest layer, secured by a first charge over the site and repaid before anything else. It typically covers 55 to 70 percent of development cost and is priced the lowest of any layer because the first charge protects it. This is the foundation of the stack: it sets the terms everything above it has to work around. Where the senior layer itself needs arranging, Construction Capital covers that market whole of market.

Mezzanine debt

Mezzanine debt is the middle layer, secured by a second charge and repaid after the senior lender but before any equity. It usually covers a further 15 to 30 percent of cost, lifting combined leverage to 85 to 95 percent, and is priced indicatively from 12 percent a year to reflect its subordinated position. Mezzanine is the layer we lend from our own book. It is the tool that lets a developer build a larger scheme, or more schemes at once, without tying up all their cash. Our full primer on mezzanine debt covers the mechanics.

Preferred equity

Preferred equity is an ownership interest that ranks ahead of common equity but behind all the debt. Unlike mezzanine, it is not secured by a charge; it takes a preferred return before the common equity holders see a profit. It appears when a senior lender will not permit a second charge, or when the gap is better filled by an equity-style layer than by debt. We compare the two directly in preferred equity versus mezzanine.

Common equity

Common equity is the developer's own capital, the top of the stack. It is repaid last, absorbs the first loss if the scheme underperforms, and in return keeps all the profit once every other layer is satisfied. It is the riskiest position and the one with the most upside. Where a developer wants to share that layer rather than fund it alone, JV equity partners can take a slice in exchange for a profit split.

Who gets paid first: the repayment waterfall

The repayment waterfall is the order in which the proceeds of a sale or refinance flow back to each layer. It runs from the bottom of the stack upward. When a scheme completes and the units sell, the money is applied in strict priority:

Senior debt is repaid in full first, principal and interest.
Mezzanine debt is repaid next, once the senior lender is whole.
Preferred equity receives its preferred return after the debt is cleared.
Common equity keeps whatever remains, which is the developer's profit.

The waterfall works the same way in a default, and this is where position matters most. If a scheme sells for less than the total funding, the shortfall is absorbed from the top down. Common equity is wiped out first, then preferred equity, then mezzanine, and only in a severe shortfall does the senior lender take a loss. That is exactly why senior debt is cheap and common equity is expensive to the project: the price of each layer is the price of its place in this queue.

Worked example: a £5m development

The clearest way to see the stack is to build one. Take an illustrative scheme with a total cost of £5m and a gross development value that supports a healthy profit on cost. Here is how a high-leverage stack might be assembled.

Layer	% of cost	Amount	Indicative cost	Repaid
Senior debt	65%	£3.25m	7.5% a year	1st
Mezzanine	25%	£1.25m	15% a year	2nd
Common equity	10%	£500k	Keeps the profit	Last
Total	100%	£5m	Blended near 10%

Illustrative only. Every scheme is priced and structured case by case.

Without the mezzanine layer, the developer would need £1.75m of equity to sit behind the £3.25m senior loan. With mezzanine filling 25 percent of cost, the equity requirement drops to £500k, and the £1.25m freed up can seed the next scheme. The blended cost of the whole stack lands close to 10 percent a year, even though mezzanine on its own is priced at 15 percent, because that rate applies only to the middle slice. You can run your own numbers on the mezzanine leverage calculator.

How to build an optimal capital stack

An optimal stack is not the one with the most leverage. It is the one that funds the scheme at the lowest blended cost the risk will bear, while leaving enough headroom to survive a wobble. Building it means working from the bottom up:

Start with senior. Establish how much first-charge debt the scheme supports, because every layer above it is priced off what is left.
Size the gap. The difference between the senior facility, your available equity and the total cost is the gap the middle layer has to fill.
Choose the middle layer. Mezzanine debt is usually the cheaper option; preferred equity fits when the senior lender will not allow a second charge. Our guide to structuring a 90 percent plus LTC stack works through this step in detail.
Keep a contingency. A stack with no slack is fragile. Preserving some equity or facility headroom protects you against cost overruns.
Match the exit. Every layer is repaid from the same sale or refinance, so the exit has to be realistic enough to clear the whole stack with margin to spare.

Risk and return by layer

The logic of the stack is that risk and return climb together. Each step up trades safety for reward:

Layer	Risk	Cost to project	Upside
Senior debt	Lowest	Lowest	Fixed interest only
Mezzanine debt	Moderate	Higher	Fixed interest only
Preferred equity	High	Higher still	Preferred return, sometimes profit share
Common equity	Highest	Residual	All remaining profit

For the developer, adding debt layers is leverage: it lifts the return on the equity actually deployed when a scheme performs, and it magnifies the pain when it does not. The art is using enough leverage to make the equity work hard without loading the scheme so heavily that a modest setback wipes out the margin.

Leverage against cost and against value

Two measures frame how tall a stack can go. Loan to cost measures each layer against the total development cost, and it is the figure most often quoted for senior and mezzanine leverage: a combined 90 percent loan to cost means 90 percent of the build cost is funded by debt. Loan to gross development value, or loan to GDV, measures the same debt against the finished value of the scheme rather than its cost. Lenders watch both. A stack can look aggressive on loan to cost yet sit comfortably against GDV if the scheme carries a healthy profit margin, because the value on completion is well above the cost of getting there. The gap between cost and gross development value is, in effect, the cushion that protects the upper layers of the stack if sales come in soft.

What are the requirements for capital stacking?

Assembling a multi-layer stack is not automatic. Lenders in the upper layers set conditions before they will sit behind, or above, one another:

A senior lender that permits subordinate layers. The senior facility has to allow a second charge and sign an intercreditor agreement, or the middle layer cannot be debt at all.
Sufficient margin. The scheme needs enough profit on cost to absorb the higher-priced upper layers and still leave the developer a return.
Security and structure. A clean special purpose vehicle holding the site, a first and second charge that can be registered in order, and personal guarantees where the mezzanine lender requires them.
Certainty on planning and cost. Full planning permission and a professional, fixed cost plan, so every layer is lending against a defined scheme rather than a moving target.
A credible exit. One realistic sale or refinance that repays the entire stack, since all the layers draw on the same event.

What is the 80/20 rule in the capital stack?

The 80/20 rule is a rough shorthand, not a fixed law. In a private equity or development context it usually describes a split where debt funds the large majority of a project, often around 80 percent, and equity provides the smaller remainder, around 20 percent, while the equity keeps most of the residual profit once the debt is repaid. It captures the basic leverage bargain of the stack: a thin slice of equity controls a much larger asset, and is rewarded with the upside for taking the first-loss position. The exact ratio varies with the scheme, the developer's track record and the appetite of each layer, so treat 80/20 as an illustration of the principle rather than a target to hit.

Practical considerations for UK developers

A few things decide how much of a stack you can actually assemble, and on what terms:

Track record. Completed schemes are the single biggest factor in the leverage and pricing a lender will offer. More completions generally means a taller, cheaper stack.
Profit on cost. A scheme needs enough margin, typically 20 percent or better, to absorb higher-cost layers and still make sense.
Planning and cost certainty. Full planning permission and a professional cost plan give every layer the confidence to lend.
The intercreditor agreement. Any senior plus mezzanine structure needs one, governing drawdown priority, the waterfall, standstill and enforcement between the two lenders. It is a known quantity between active funders, not usually a fight. See our guide to intercreditor agreements.
The exit. Sales rates and values move, so the exit that repays the stack has to be tested against realistic, not optimistic, assumptions.

Build it with us

We lend the mezzanine layer from our own book and arrange senior and equity whole of market where they fit better elsewhere. Start with our overview of mezzanine finance or see how it works, then send us the scheme with costs, GDV and your senior terms if you have them.