What Does the Money Cost?
Why WACC is an underused framework for evaluating real estate investments, development deals, and affordable housing
Why WACC Belongs in Real Estate Underwriting
Real estate people love metrics and acronyms, but that’s another conversation.
We talk about cap rates, IRR, cash-on-cash return, yield-on-cost, debt service coverage, loan-to-value, residual land value, and development spread. Each of these metrics is useful. Each tells us something different about the property, the financing, or the risk profile of a deal.
But there is one question I think real estate professionals do not ask often enough:
What does the money actually cost?
That is where the Weighted Average Cost of Capital, or WACC, becomes useful. WACC is a common corporate finance concept, but I think it is underused in real estate, especially in real estate development and affordable housing development. At its core, WACC is the blended cost of the capital used to finance an investment. It asks a simple but important question: if this property is financed with debt, equity, and other capital sources, what return does the property need to generate to justify that capital stack?
That question matters because a deal does not create value simply because the projected return is positive. It creates value when the return generated by the property exceeds the cost of the capital required to buy it, build it, or preserve it.
Put differently: before we ask whether the return is attractive, we should understand what the capital requires.
WACC in Plain English
The formal definition of WACC is the weighted average cost of a company’s capital across sources such as debt, equity, and preferred stock. In corporate finance, it is often used as a discount rate when valuing future cash flows. But we do not need to overcomplicate the concept. WACC is really about one thing: understanding the cost of the money.
The formula is usually shown like this:
Where:
E = value of equity
D = value of debt
V = total value of debt and equity
Re = cost of equity
Rd = cost of debt
T = tax rate
The formula may look technical, but the concept is practical. Debt has a cost. Equity has a cost. Preferred equity has a cost. In real estate, even capital that appears “cheap” has a cost. A soft public loan may have a below-market interest rate, but it may also come with affordability restrictions, reporting requirements, distribution limits, and approval rights. Tax credit equity can dramatically reduce the need for conventional debt, but it also brings delivery obligations, adjuster risk, guarantees, and long-term compliance.
The cost of capital is not always visible in the interest rate. Sometimes it is hidden in the structure. A simple example helps. Suppose a project is financed with 60% debt at 7% and 40% equity requiring a 14% return.
The simplified WACC would be:
60% × 7% = 4.2%
40% × 14% = 5.6%
Blended cost of capital = 9.8%
That does not mean every deal projected to earn more than 9.8% is good, or every deal projected below 9.8% is bad. Real estate is more nuanced than that. But it gives the investor or developer a starting point.
Is the property expected to generate enough return to compensate the people and institutions providing the capital?
That is the question WACC forces us to ask.
Why I Think WACC Is Underused in Real Estate
Real estate underwriting often starts with the asset.
What are the rents? What is the vacancy? What is the cap rate? What is the exit value? What is the stabilized NOI? What is the IRR? What is the yield-on-cost?
Those are important questions, but they tend to focus on the return side of the equation. WACC connects the return to the capital required to produce it.
A projected 15% IRR might look attractive on the surface. But what if the deal requires expensive preferred equity, floating-rate construction debt, personal guarantees, a long entitlement process, and uncertain exit pricing? Suddenly, that 15% return may not be as compelling.
On the other hand, a 7% or 8% return may look modest. But what if the project is supported by low-cost permanent debt, stable rental assistance, predictable cash flow, and limited downside risk? In that case, the return may be reasonable for the risk being taken.
That is why WACC is helpful. It does not replace IRR, cap rates, DSCR, or yield-on-cost. It gives those metrics context.
The broader corporate finance point is that companies create value when they invest capital at returns above their cost of capital. The same logic applies to real estate. A property is not attractive in the abstract. It is attractive at a certain price, with a certain business plan, using a certain capital stack.
Translating WACC to Real Estate
In corporate finance, WACC is usually framed around debt and equity. In real estate, the capital stack can be much more layered.
A straightforward acquisition might include senior debt and sponsor equity. A development deal might include land equity, construction debt, mezzanine debt, preferred equity, and common equity. An affordable housing deal might include tax credit equity, tax-exempt bonds, subordinate public loans, grants, deferred developer fee, operating subsidies, property tax abatements, and sponsor funds.
Each source has a different place in the stack. Each source has a different risk profile. Each source has a different expectation.
The senior lender wants to be repaid with interest and will focus on collateral, loan-to-value, debt yield, and debt service coverage. The preferred equity investor may want a fixed return and priority over common equity. The common equity investor wants upside after everyone else is paid. The public lender may charge a low interest rate, but it may also require long-term affordability, compliance, reporting, and approval rights.
WACC helps organize those expectations into one framework.
It gives the developer a way to ask: what is the blended return requirement embedded in this capital stack?
This matters because cheaper capital is not always better capital. Sometimes cheap capital is patient, flexible, and mission-aligned. Other times, cheap capital comes with restrictions that limit flexibility, slow execution, or reduce future optionality.
The goal is not simply to find the lowest-cost money. The goal is to create a capital stack that fits the risk, timing, purpose, and economics of the project.
Why This Matters Even More in Development
Development is not one risk. It is a sequence of risks.
There is land acquisition risk. Entitlement risk. Design risk. Environmental risk. Construction pricing risk. Interest rate risk. Lease-up risk. Operating risk. Permanent financing risk.
A project also changes risk categories over time. A raw piece of land waiting for rezoning is not the same risk as a fully entitled project with approved plans. A building under construction is not the same risk as a stabilized operating asset. A project approaching conversion is not the same risk as a project still trying to close its construction loan.
That is why using one return target for every real estate deal can be misleading.
A developer may say, “We need a 15% IRR.” But 15% for what? A speculative ground-up development? A stabilized acquisition? A preservation deal? A fully subsidized affordable housing development? A mixed-income public-private partnership?
The required return should reflect the risk, timing, and capital stack.
WACC does not eliminate judgment. It improves judgment by making the assumptions more visible.
In development, cost of capital is not just a finance concept. It is also a project management concept. Delays increase carrying costs. Cost overruns require more capital. Higher interest rates reduce proceeds. Investor expectations shift over time. A project that cleared the cost of capital at initial underwriting may no longer clear it two years later if the budget, schedule, interest rate environment, or operating assumptions have changed.
That is why I find the framework useful. It keeps the conversation grounded.
Affordable Housing and the Hidden Cost of Complexity
Affordable housing makes this even more important.
In many affordable housing transactions, the apparent cost of capital may be lower than in a conventional market-rate development. A project may benefit from tax credit equity, tax-exempt bonds, soft public debt, grants, rental assistance, property tax abatements, or other subsidy sources.
But affordable housing also comes with a hidden cost: complexity.
Rents are restricted. Income limits apply. Compliance is ongoing. Public approvals can be layered. Capital sources may have different deadlines, underwriting standards, and closing requirements. Residual cash flow may be limited. Developer fees may be deferred. Long-term affordability restrictions may reduce future optionality.
So the question is not simply, “Did we lower the interest rate?” or “Did we reduce the amount of conventional debt?”
The better question is:
Did we create a capital stack that allows the project to work financially while still achieving the public purpose?
That is where WACC becomes a helpful framework, even if it is not a perfect answer.
Affordable housing often lowers the visible cost of capital but increases the hidden cost of complexity.
That does not mean the tradeoff is bad. In many cases, it is exactly the tradeoff required to create long-term affordable housing. But it should be understood clearly. Public capital, tax credit equity, and soft debt can make a project possible, but they also shape the economics, timeline, operations, and long-term flexibility of the property.
Mission does not eliminate math. WACC helps connect the mission to the math.
How I Use WACC as a Developer
I do not use WACC as the only metric in real estate. It is not a magic number. It can create false precision if the assumptions are weak, if the capital stack changes over time, or if the cost of equity is guessed without understanding what investors actually require.
But I do use it as a discipline.
When I look at a development opportunity, I am not only asking whether the IRR looks attractive. I am asking whether the return is appropriate for the capital stack required to get the project built, leased, stabilized, and converted.
WACC helps me ask better questions.
What does each source of capital require?
Is the projected return above the blended cost of capital?
Are we being compensated for the risk we are taking?
Is debt improving the transaction, or is it simply increasing risk?
Is the equity return appropriate given the timing, uncertainty, and residual position?
Are subordinate sources truly lowering the cost of capital, or are they shifting the cost into restrictions, compliance, and execution risk?
Does the deal still work if interest rates rise, construction costs increase, rents soften, or the schedule slips?
Those questions are often more valuable than the formula itself.
Real estate is capital intensive. Small changes in financing terms can determine whether a deal works or fails. A lower interest rate can create value. Too much debt can destroy it. Cheap capital can be helpful. Complicated capital can be expensive in ways that are not obvious on day one.
WACC gives us a way to see the capital stack a little more clearly.
The Return Has to Clear the Cost of the Money
Every real estate project has a cost of capital, whether we calculate it or not.
The lender knows its interest rate. The equity investor knows its return target. The public agency knows its policy requirements. The tax credit investor knows its pricing, and compliance expectations. The developer knows the risk it is taking to bring the project together.
WACC brings those expectations into one conversation.
That is why I believe it is an underused metric in real estate. Not because it replaces traditional underwriting tools, but because it helps explain what those tools are really trying to tell us.
A project should not move forward simply because the IRR looks good, the cap rate seems reasonable, or the story is compelling. It should move forward because the expected return is strong enough to clear the cost of the capital required, adjusted for the risk, complexity, and purpose of the investment.
In market-rate real estate, that discipline helps investors avoid overpaying or overleveraging.
In development, it helps sponsors understand whether they are being compensated for the risks they are taking.
In affordable housing, it helps balance financial feasibility with public purpose.
The question is simple, but powerful:
What does the money cost and can the property generate enough value to justify it?
Every project has a cost of capital. WACC simply forces us to look at it directly.
About the Author
Charles Sims is an affordable housing developer and community builder with over a decade of experience leading real estate projects that prioritize people, equity, and long-term impact. He has helped shape award-winning multifamily communities across the Mid-Atlantic and South Florida. Charles is passionate about creating housing that not only provides shelter but supports dignity, stability, and connection.
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