Adaptive Reuse Feasibility Study: Commercial-to-Residential and Mixed-Use Conversion

An adaptive reuse feasibility study is an independent, third-party analysis of whether an existing building, designed and built for one use, can be converted to another use or mix of uses and achieve the income needed to service a specific loan. It is distinct from an appraisal, which concludes a value as-is and as-converted, and from an architect's test fit, which concludes what will physically fit. The feasibility study concludes whether the conversion pencils and, where it does, under what conditions.

The sequence is the reverse of a new-construction study. In new construction the market sizes the building. In a conversion the building sizes the market: its floor-plate depth decides how many units can have a window, its structure decides where plumbing can run, its envelope and systems decide the cost, and its age and district decide whether a tax credit is available. The study therefore begins with the building, then asks whether the uses the building can hold are uses the market will pay for, and only then builds the projection; where the result is more than one use, the mixed-use feasibility study method governs the combination.

Conversion work divides into three lending situations, and the study is written for the one in front of the lender.

The first is the owner-occupied conversion financed under SBA 7(a) or 504, where an operating business buys a building, occupies at least 51 percent of it, and converts the remainder, usually upper floors, to apartments or offices for lease. The square footage test comes first, and the main-street version of this project is covered in full on the SBA mixed-use feasibility study page.

The second is the historic rehabilitation, where a certified historic structure in a National Register district is converted with the federal 20 percent rehabilitation tax credit as a source, under the Secretary of the Interior's standards and the state historic preservation office's review. The credit changes the capital stack and the design constraints at once, and the study carries both.

The third is the by-right conversion of an office, retail or warehouse building to residential or mixed-use under the state statutes enacted between 2022 and 2026, financed conventionally and often by an agency lender on the residential component, where the entitlement risk that used to dominate such projects has been replaced by a statutory checklist and the risk has moved to the building and the cost.

No federal regulation makes a conversion study automatic. Under 13 CFR 120.160(b), SBA may require a feasibility study, and SOP 50 10 8.1, in force for loans numbered on or after October 1, 2026, leaves the decision with the lender or CDC; in a conversion the prior use's income says nothing about the next use, so the file rests entirely on projections and lenders request a study in nearly every case. Under 7 CFR 5001.306, a USDA Business and Industry guaranteed loan above $1 million to a new business requires an independent feasibility study, and a converted building is a new business whatever stood there before. Conventional lenders and the agency lenders who finance the residential component of a conversion apply their own credit policies, which for a building with no operating history in its new use include a third-party review of the conversion budget and the market for the new use.

The reader is a credit officer, an SBA district office, a CDC loan committee, a USDA state office, a historic tax credit investor's counsel, or an agency underwriter reading only the residential half. The study is written for those readers, not for the borrower, and MMCG accepts no referral fees, contingent fees or financing arrangements that would compromise that position.

Between 2022 and 2026 a run of state laws removed the local discretionary approvals that conversion and mixed-use projects used to require, and the study is written into the specific statute that governs the subject's city and county.

Texas SB 840, effective September 1, 2025, permits residential and mixed-use development on sites zoned for office, commercial or warehouse use without rezoning in municipalities of more than 150,000 people within counties of more than 300,000, and sets conversion rules for buildings at least five years old where at least 65 percent of the building becomes multifamily. The law reaches no county and no smaller city, so the study states whether the subject's municipality is inside the threshold.

Washington's E2SSB 6026, signed March 27, 2026 and effective June 11, 2026, legalizes residential use in commercial and mixed-use zones and limits ground-floor commercial mandates, and gives local governments eighteen months from the effective date to bring their codes into compliance. In the interim the study states whether the subject's jurisdiction has acted.

New Hampshire's HB 631, codified at RSA 674:77 and 78, requires multifamily by right on commercially zoned land from July 1, 2026 and exempts adaptive-reuse conversions from certain dimensional limits.

Virginia's section 15.2-2209.4, effective July 1, 2026, caps minimum parking at one half space per unit for residential and mixed-use projects near transit, which for a converted office building with a fixed parking supply is often the difference between a feasible unit count and an infeasible one.

California's AB 2011 and SB 6 opened commercially zoned land to residential development subject to affordability and labor standards, AB 2097 removed parking minimums within a half mile of major transit, and SB 423 extended the streamlined ministerial approval of SB 35. The study states which statute the subject qualifies under and which standards it triggers. Florida's Live Local Act, which opens commercially and industrially zoned land to qualifying affordable multifamily, is reviewed in MMCG's analysis of the Live Local Act.

The consequence for underwriting is that the chapter a conversion study used to spend on entitlement risk has become, in these states, a table of statutory thresholds with the subject's figures beside them. The study's weight has moved to three things: the building, the cost and the market for the new use.

The cost side has not eased. Rider Levett Bucknall's national construction cost index rose 4.45 percent in the year to July 2026, with the latest quarterly increase the highest in two years and liquid asphalt up 16.4 percent. Conversion carries items new construction does not: selective demolition, hazardous material abatement in any building of the vintage most conversions involve, structural reinforcement for new openings and shafts, and the fire separation, egress and elevator work that a change from a commercial to a residential occupancy requires. The study prices each as its own line.

The study's first chapter is the building, and it answers five questions before the market is consulted.

Floor plate and window line. Residential units need daylight and a code-compliant window in every habitable room, and a floor plate more than about sixty feet from exterior wall to core leaves a dark interior that cannot be a bedroom. The study measures the plate, the depth from window to core, and the ratio of perimeter to area, and derives the unit count and mix that the plate supports. A narrow main-street building converts floor by floor; a deep suburban office building may convert only at its perimeter, with the core given to corridor, storage and amenity, and the study states the yield in net rentable square feet per gross square foot of building.

Structure. Plumbing for kitchens and bathrooms on every floor needs vertical runs the original building never had, and the study records the structural system, the floor-to-floor height, the location and size of new shafts, and the structural engineer's finding on where they can be cut.

Envelope and systems. Operable windows, insulation, a residential ventilation system, individual metering and in-unit HVAC replace the central systems of a commercial building, and the study prices the replacement rather than assuming reuse.

Code. A change of occupancy from business or mercantile to residential triggers fire separation between any remaining commercial floor and the residential floors, a second means of egress, sprinklers, accessibility under the applicable code, and in any building of three or more stories an elevator where none exists. The study lists each triggered item from the code official's determination or the architect's code study and prices it.

Historic status and the credit. Where the building is a contributing structure in a National Register district or individually listed, it is a certified historic structure for the federal 20 percent rehabilitation tax credit, and the Secretary of the Interior's standards govern what can be done to its exterior and its character-defining interior spaces. The study records the status, the state historic preservation office's position, the substantial rehabilitation test that qualified expenditures must exceed the greater of $5,000 or the adjusted basis, and the design constraints the credit imposes on unit layout, window replacement and storefront treatment.

Only once the building has fixed the program does the study turn to the market, and it analyzes each resulting use on its own evidence.

Residential floors follow the multifamily method: rent and vacancy from the American Community Survey for the city and the tract, the HUD Fair Market Rent schedule for the county, dated listings with unit size so that rent per square foot can be derived, the municipal housing study where one exists, and the pipeline of permitted and under-construction units. In most small and mid-sized downtowns the published evidence is a citywide median, a handful of new-build listings and an older-product floor, and the study says so and positions the converted units between the Fair Market Rent and the new-build listing according to the finish level the building and the credit's standards allow. See the multifamily feasibility study page.

A retained or new commercial floor follows the retail method: the downtown trade area, the published leakage and surplus analysis, the competitive set verified property by property, and, where an operating business occupies it, the operator's projection from the concept's public benchmarks and the local wage base with an imputed market rent carried as a check. A ground floor that must stay commercial under the statute or the district's guidelines, but for which the market shows no tenant, is a cost the residential must carry, and the study runs the ground-floor-dark case. See the retail feasibility study page.

Where the conversion creates a hotel, the hotel method applies with its own segmented demand, verified competitive set, ramp and USALI projection. See the hotel feasibility study page.

The conversion budget is the study's second decisive chapter, and it is benchmarked against the public record rather than taken from the developer.

The record for small historic mixed-use conversions is the state historic credit award lists, which publish total project cost by project. The most recent round in Ohio shows projects of this type, a restaurant or bar at grade and four to twelve apartments on the floors above in two- to four-story blocks, at total project costs from about $1.3 million to $5.0 million, with a new elevator among the larger single items where one was added. Those lists do not publish building area, so they support a total-budget check rather than a cost per square foot, and the study says so. Where a per-square-foot figure is available, as for a 17,000-square-foot Indiana garage converted to a brewery and restaurant at more than $171 per square foot, the study states its scope and its vintage. New-build apartment cost in the same market serves as a ceiling: a 120-unit downtown Columbus, Indiana building with structured parking and commercial space was estimated at $30.9 million in 2025, about $257,500 per unit, and a conversion that approaches that figure has lost the argument for converting.

The study presents the budget by line item: acquisition, selective demolition and abatement, structural work, shafts and vertical circulation, envelope, mechanical, electrical and plumbing, fire protection and life safety, the elevator, residential fit-out by unit, commercial fit-out, site and parking, soft cost, permit and utility connection fees from the published municipal schedule, financing cost, the credit's syndication or bridge cost, and reserves. It states the contingency the lender should carry for a building whose conditions are not fully known until demolition opens the walls, and it escalates every pre-2026 benchmark at the current index.

The capital stack is stated by program and source. Under SBA 504 an owner-occupied conversion by an established operator sits at the 10 percent borrower contribution and by a new entity at 15 percent, since a converted main-street building is general-purpose collateral; the 25-year debenture applies where real estate is 51 percent or more of proceeds; and where the operator's staffing does not meet the job standard of one job per $95,000 of debenture, the public policy goal at 13 CFR 120.862 for revitalizing a business district with a written revitalization or redevelopment plan is the usual substitute. The combined SBA exposure across 7(a) and 504 is $10 million. The federal historic credit is carried as a source with its timing and its monetization cost, and the study presents the stack with and without it because lenders differ on whether it counts toward the borrower's contribution. State credits are confirmed with the state office rather than carried from a prior year; Indiana, for example, eliminated its commercial credit in 2016. Under USDA B&I, a converted mixed-use building must earn at least 50 percent of projected revenue from business use, and housing whose primary purpose is independent housing is ineligible. Conventional and agency lenders size the residential to their own DSCR and loan-to-value and the commercial, where it is counted at all, to a haircut net operating income.

The DSCR is reported at each year on the full debt service, decomposed by use where more than one use remains, with the ground-floor-dark case, the residential vacancy steps, the absorption delay and the cost-overrun case run. The conversion-specific case is the overrun: hard cost escalated by the contingency the study recommends, with the DSCR and the additional equity or reserve that result. The study concludes feasible, feasible with conditions, or not feasible, and states the condition in the lender's terms, which in a conversion is most often a fixed-price contract or a guaranteed maximum price, a pre-lease or owner-occupancy of the commercial floor, or a reserve that carries the project through lease-up.

Main-street commercial blocks, two and three stories with a storefront below and vacant or underused upper floors, are the most common conversion in SBA lending and the easiest to convert: shallow plates, windows on two sides, and a district listing that brings the federal credit. Their constraint is code, above all egress and the elevator question, and their market is the downtown residential submarket. The Columbus, Indiana case study is this type.

Suburban and downtown office buildings are the conversions the state statutes were written for and the hardest to convert: deep plates, sealed curtain walls, central systems and a core that cannot be moved. Their feasibility turns on the plate-depth yield, the envelope replacement cost and whether the acquisition basis reflects the building's loss of value as an office rather than its replacement cost.

Warehouses and industrial buildings offer high ceilings, heavy structure and large plates, and convert to loft residential at the perimeter with interior space given to amenity, storage or a commercial use. Their constraint is environmental: the study records the Phase I and any Phase II findings and the abatement and remediation cost.

Retail buildings and former department stores, big boxes and enclosed malls convert to residential only at the perimeter, to mixed-use with new openings cut through the roof or the plate, or to uses that do not need windows: storage, medical, education, data. The study tests each program the plate supports, in the manner of a highest and best use study, and reports which one the market and the budget favor.

Institutional buildings, schools, churches, hospitals and courthouses, carry heavy structure, generous floor-to-floor heights and, often, a listing that brings the credit, together with layouts that resist residential subdivision and parking that reflects their original use. Their feasibility turns on the unit yield against the preservation standards.

An MMCG adaptive reuse feasibility study runs between 100 and 150 pages and includes the building analysis with plate, structure, envelope, code and historic status, the program the building supports with unit count and mix, the statutory eligibility table for the subject's jurisdiction, the market analysis for each resulting use on its own evidence, the conversion budget by line item benchmarked against the public record with the recommended contingency, the capital stack by program with the historic credit as a timed source, the DSCR schedule by year with its decomposition by use, the ground-floor-dark, absorption and cost-overrun sensitivities, and a signed conclusion. Comparables and competitors are verified against public records, award lists and dated listings under MMCG's methodology, and the study states which figures are primary-verified, which are carried from licensed or older sources, and which could not be verified and are carried as stated assumptions.

Standard delivery is 9 to 16 business days from engagement and receipt of the project file, including the architect's test fit and the code study where they exist, with rush delivery from 5 business days. Fees begin at $4,900 for a single-building SBA 7(a) conversion study and range from $7,500 to $15,000 for SBA 504 and historic credit studies depending on the number of resulting uses, units and scenarios. Conventional, agency and multi-building conversion studies are quoted on scope. Payment is 50 percent at engagement and 50 percent at delivery. MMCG has offered a contractual acceptance commitment on every study since founding: revisions required by the lender or agency are made at no additional cost.