Financing an office-to-residential conversion
A conversion is priced like ground-up construction on a building that earns nothing while the work runs, and the senior loan is sized accordingly. This is where the gap comes from, which parts of a conversion scope a C-PACE programme will actually fund, how the assessment stacks with a bridge or construction loan, and why the lender consent conversation is harder on a conversion than on a retrofit.
Published 2026-09-14 · last checked 2026-09-14
A conversion is the hardest thing in commercial real estate to finance, and the reason is arithmetic rather than sentiment. You are spending ground-up construction money on a building that produces no income while the work runs, against a valuation that only exists once it is finished and leased. A senior lender sizes to that reality. What is left over is the gap, and it is usually larger than the equity you planned to put in.
That gap is the shape C-PACE fills, and the market has noticed. CoStar reported on 15 March 2026 that 2025 C-PACE lending volume reached a record $3.5 billion by most industry estimates, and that the legislation is now active in 40 states plus Washington, D.C. Urban Land reported on 26 January 2026 that the average C-PACE transaction reached $40 million in 2025, double the $19 million average in 2024. A product that used to pay for boiler replacements is now sized to carry buildings.
Where the gap actually comes from
Nothing about a conversion is a retrofit. The floor plate that made the building work as an office is the problem you are paying to solve. J.P. Morgan, writing on 27 February 2026, noted that a sprawling footprint often requires drilling light wells for interior rooms lacking windows — which is structural work, at structural cost, before a single apartment exists.
Meanwhile the collateral is worth less than it will be and more than it is. A construction lender underwriting a conversion is lending against a building whose current use is being deliberately destroyed. The loan gets sized conservatively, and the hole below it has to be filled by something — equity, mezzanine, preferred, or an assessment.
The clearest illustration of what that stack can look like is the largest C-PACE deal ever done, and it is a conversion. Nuveen Green Capital and DC Green Bank announced on 6 January 2026 that Post Brothers closed $465 million of C-PACE financing alongside a $110 million first mortgage from Mavik for The Geneva, a 604,000-square-foot office complex at 1825–1875 Connecticut Avenue NW in Washington, D.C. becoming 429 market-rate units, 42 extended-stay rentals, 61 affordable units and 57,000 square feet of commercial space. The two pieces together: $575 million.
Read the two numbers next to each other. The assessment is more than four times the first mortgage. On that deal, C-PACE was not the piece that topped up the stack — it was the stack, and the mortgage filled in around it. Post Brothers president Matt Pestronk told Urban Land on 26 January 2026 that C-PACE financing was available on better terms than construction financing. When the senior market is pricing your conversion risk, an assessment priced — per CoStar, 15 March 2026 — at roughly the 10-year Treasury plus 3%, fixed, over up to 30 years, stops being an alternative and starts being the plan.
It is not the only one. CoStar reported the same day that PACE Loan Group provided a $100 million C-PACE loan for Patmos Hosting, a 421,112-square-foot office campus conversion in Kansas City. Commercial Observer reported on 2 June 2026 that CounterpointeSRE’s previous record was $255.9 million for the Aronson Building conversion in San Francisco.
Which scope items qualify
This is where conversion projects get a pleasant surprise and then a limit.
The pleasant surprise: a conversion rebuilds precisely the systems C-PACE is designed to fund. Nuveen Green Capital’s announcement describes The Geneva’s C-PACE proceeds as funding energy and water efficiency measures including HVAC, lighting, hot water and building envelope improvements. In an office-to-residential conversion, those are not incidental line items — you are replacing the entire mechanical system because an office HVAC design cannot serve apartments, and you are opening the envelope because residential code requires light and air that the building does not have.
The NYC Accelerator PACE Financing Program Guidelines, version 3.1 revised 8 September 2025, list eligible measures including envelope work — window and door replacement, caulking, weatherstripping, air sealing, insulation — heating and cooling system upgrades, lighting, and renewable energy systems including solar thermal, solar photovoltaic, wind, geothermal and fuel cells. Commercial Observer reported on 2 June 2026 that New York City expanded eligible projects to include gut rehabilitations in addition to renovations, and that in spring 2026 it became one of the first jurisdictions to include embodied carbon in the calculation of how much C-PACE financing adaptive reuse projects are eligible for.
The limit: everything else in your budget. Unit fit-out, kitchens, leasing costs, developer fee, land carry. Those are real costs and no programme will assess them. The practical step is to have your engineer separate the eligible scope early, because that number — not the project budget — is what a provider can size against. Our C-PACE calculator runs the sizing once you have it.
Caps then apply on top. The NYC guidelines state that unless otherwise noted in the Technical Guidance Supplement, the PACE loan amount cannot exceed 30% of total project costs. Connecticut Green Bank’s guidelines, dated 15 March 2024, take a different approach: no percentage-of-value ceiling, but the term may not exceed the weighted average effective useful life of the improvements, and cannot exceed 25 years unless the Green Bank approves otherwise in its sole discretion. Two programmes, two entirely different binding constraints. Check yours before you model anything.
Stacking it with the senior loan
C-PACE is not a substitute for a construction loan on a conversion; it sits underneath one. The Geneva pairs it with a first mortgage. CoStar reported on 15 March 2026 that Harper Square in Philadelphia, a 267-unit development, combined $60 million in C-PACE with $113 million in senior construction financing from Barings and CounterpointeSRE.
What the assessment changes for the senior lender is priority. The EPA’s C-PACE page, last modified 7 July 2026, states that in the event of foreclosure, any past due payments related to the PACE lien take priority over the mortgage and other loans. That is the whole reason consent exists — and it is why a bridge or construction lender reads the term sheet carefully rather than waving it through. If you are weighing the two products against each other rather than stacking them, our bridge loan comparison covers that decision directly.
Why consent is harder on a conversion
Every C-PACE deal needs the existing mortgage holder’s written consent. Connecticut Green Bank’s guidelines require the owner to obtain written consent from any existing mortgage holder and to give thirty days’ written notice before the lien is recorded. The NYC guidelines require all holders of mortgages or deeds of trust to consent on the programme’s own form. There is no version of this that happens afterwards.
On a conversion, three things make that ask heavier than on a retrofit. The lender is being asked to accept a priority position on a building with no operating income to point at. The assessment is often large relative to the mortgage — at The Geneva, several times it. And the consent has to be secured while the capital stack is still being assembled, which means the senior lender is signing before the equity is fully committed.
None of that makes it impossible; it makes it early. The ask goes out at term sheet stage, not at closing. Our guide to the lender consent conversation sets out what to send and what to expect.
The honest version
If your conversion is small, if the eligible scope is a thin slice of the budget, or if your existing lender has already said no, C-PACE will not rescue the deal — and you should know that in week one rather than month four. When C-PACE is the wrong answer is the companion to this page.
But if you are converting an office building, the eligible scope on a conversion is unusually deep, the term is long, the rate is fixed, and the record is no longer theoretical. Start by separating the eligible scope, check the programme rules for the jurisdiction the building actually sits in — the state-by-state position is where that starts — and raise consent with your lender before anyone has drawn a capital stack on a page.
Questions people actually ask
Can C-PACE fund an office-to-residential conversion?
Yes, and the largest C-PACE transaction on record is one. Nuveen Green Capital and DC Green Bank announced on 6 January 2026 that Post Brothers had closed $465 million of C-PACE financing alongside a $110 million first mortgage from Mavik — $575 million between them — for The Geneva, the conversion of a 604,000-square-foot office complex at 1825–1875 Connecticut Avenue NW in Washington, D.C. into 429 market-rate units, 42 extended-stay rentals, 61 affordable units and 57,000 square feet of commercial space. Whether your own conversion can use C-PACE depends on the programme governing your property: CoStar reported on 15 March 2026 that C-PACE legislation is active in 40 states plus Washington, D.C., and each programme sets its own eligible scope and sizing rules.
Which parts of a conversion scope are C-PACE eligible?
The categories, not the conversion as a whole. Nuveen Green Capital's 6 January 2026 announcement for The Geneva describes the C-PACE proceeds as funding energy and water efficiency measures including HVAC, lighting, hot water and building envelope improvements. The NYC Accelerator PACE Financing Program Guidelines, version 3.1 revised 8 September 2025, list eligible measures including envelope work — window and door replacement, caulking, weatherstripping, air sealing and insulation — heating and cooling system upgrades, lighting, and renewable energy systems including solar thermal, solar photovoltaic, wind, geothermal and fuel cells. Unit fit-out, leasing costs and developer fees are not in those categories, so the eligible figure on a conversion is always smaller than the project budget.
How much of a conversion can C-PACE cover?
It is capped programme by programme, not nationally, so the cap that binds you is the one in your jurisdiction's guidelines. The NYC Accelerator PACE Financing Program Guidelines, version 3.1 revised 8 September 2025, state that unless otherwise noted in the Technical Guidance Supplement the PACE loan amount cannot exceed 30% of total project costs. The Connecticut Green Bank's C-PACE Program Guidelines, version dated 15 March 2024, set no percentage-of-value cap but limit the assessment term to no more than the weighted average effective useful life of the improvements, and to 25 years unless the Green Bank approves a longer term in its sole discretion.
Will my construction lender have to consent?
Yes, and on a conversion that conversation is the critical path. The Connecticut Green Bank's C-PACE Program Guidelines, version dated 15 March 2024, require the owner to obtain written consent to the C-PACE financing from any existing mortgage holder of the qualifying property, and to give that holder written notice at least thirty days before the benefit assessment lien is recorded. The NYC Accelerator guidelines, version 3.1 revised 8 September 2025, require all holders of mortgages or deeds of trust on the benefitted property to consent on the most recent version of the programme's own mortgage holder consent form. There is no route to closing that goes around either requirement.
What happens to the assessment when I sell the converted building?
It is attached to the property rather than to you, so it does not automatically get paid off at closing. The US Environmental Protection Agency's C-PACE page, last modified 7 July 2026, states that the assessment stays with the property in the event of a sale, assuming the buyer agrees to the transfer, and that if the buyer does not agree the seller must pay the outstanding balance. That makes the buyer's view of the assessment a negotiating point in your exit, not an afterthought.
Is C-PACE cheaper than the alternatives for a conversion?
On the rate, usually — but compare all-in cost, not headline rates. CoStar reported on 15 March 2026 that C-PACE offers lower fixed interest rates ranging from 5% to 8%, against 10% to 14% for riskier financing, that it is often priced at about the 10-year Treasury rate plus 3%, and that repayment spans up to 30 years. Post Brothers president Matt Pestronk told Urban Land, in a piece published 26 January 2026, that C-PACE financing was available on better terms than construction financing. Programme administration fees, closing costs and capitalised interest during construction sit on top of the rate and vary by programme.