DSCR Loans on Mixed-Use STR Properties: What Qualifies

Why mixed-use is a threshold question before it's a math question

A DSCR loan is, by design, a residential investment-property product. Before any revenue projection or ratio calculation matters, a mixed-use property — think ground-floor retail with residential units above, or a live/work property with a commercial storefront component — has to clear a minimum residential-use threshold to even be eligible for that residential DSCR program in the first place. Fall meaningfully short of that threshold and the property needs commercial or mixed-use commercial financing instead, which is a different product with different underwriting entirely.

The threshold is generally expressed as a percentage — commonly measured by square footage, sometimes by income share — that has to be predominantly residential. Exact percentages and measurement methods vary by lender and program, so this is a confirm-directly item, not something to assume from a generic rule of thumb.

This gate typically gets checked at the appraisal stage rather than left to a borrower's self-assessment. The appraiser measuring the property will generally document the split between residential and non-residential square footage as part of the standard appraisal report, which means the residential-percentage question usually gets a definitive, third-party answer before the loan gets very far into underwriting — it isn't a negotiable estimate late in the process.

How this interacts with a short-term-rental use case specifically

For a mixed-use property where the residential portion is being operated as a short-term rental, both qualification layers stack: the residential-percentage threshold has to clear for the property to be DSCR-eligible at all, and then the STR-specific revenue methodology — comp-based projections, cap adjustments for any nightly limits, trailing-12-month data — applies to whatever the qualifying residential income actually is.

There's also a local-legality layer that stacks on top of the two lending questions. STR ordinances sometimes treat mixed-use buildings differently than pure residential buildings — for instance, some jurisdictions restrict nightly rentals in buildings with certain zoning classifications regardless of the specific unit's use. Confirm the zoning and any STR-specific carve-outs for mixed-use buildings against the legality hub before assuming the residential units are automatically eligible for nightly rental just because they're eligible for DSCR financing.

A worked example blending unit types

Picture a small mixed-use building: three residential units above a single ground-floor commercial storefront, where the residential square footage comfortably clears the program's minimum residential-use threshold. The residential units are what get evaluated under the DSCR methodology — say each unit is being run as a furnished mid-term or short-term rental with its own trailing-12-month projected income.

That asymmetry — the loan covers the whole property but only part of its income qualifies — is exactly why the residential-percentage threshold matters so much upfront. A property with a smaller residential share and a proportionally larger commercial component can look fine on total building income and still fail to qualify, because the ratio is only allowed to count the residential slice.

It's worth stress-testing that same worked example against a lower residential share to see how quickly the math turns. If the same $54,000 in qualifying residential income sat inside a building where the commercial storefront represented a much larger share of total space and debt, the fixed PITIA on the whole property wouldn't change, but the property's overall size and mortgage would likely be larger to reflect the added commercial square footage — pushing the ratio down even though the residential units' performance stayed identical. Scale matters as much as the percentage split itself.

What to confirm before you underwrite a mixed-use STR deal

Get the residential-use percentage measured and documented early — typically from the property's actual floor plans or a prior appraisal — rather than estimating it. Confirm with your specific lender both their minimum threshold and whether their program allows any blending of commercial income into the ratio, since that varies and materially changes what the property can qualify for.

1. Document the residential-versus-commercial square footage or income split from floor plans or appraisal records.
2. Confirm your target lender's minimum residential-use threshold for DSCR eligibility.
3. Confirm whether the specific program allows commercial income to blend into the ratio, or excludes it entirely.
4. Run the STR/MTR revenue methodology only on the qualifying residential portion, then divide by PITIA on the full property debt.

The bottom line for mixed-use STR deals

Mixed-use adds a qualification gate that a purely residential STR property doesn't have to clear — the residential-percentage threshold — and it typically narrows which income counts toward the ratio even after that gate is cleared. Neither of those is a deal-killer by default, but both need to be confirmed with your specific lender before you build a purchase decision around an assumed DSCR.