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DC Two-Unit Rowhome BRRRR Underwriting 2026: English Basement Math
By Jason Taken · Principal
How to underwrite a DC two-unit rowhome BRRRR with a legal English basement in 2026: rehab budget, rent split, appraisal risk, and DSCR refinance sizing.
The DC rowhome with a walk-out basement is one of the best BRRRR setups in the country. You buy a tired single-family house, rehab the upper floors for a family or roommate tenant, and legalize the lower level as a separate apartment. Two rents from one lot can carry a mortgage that one rent never could.
The catch is underwriting. The refinance only works if the appraiser counts two units, the DSCR ratio clears on combined rent, and the basement is legal by the time you apply. This guide walks through each step for 2026: buy, rehab, rent, refinance, and repeat. For the broader DC version of the strategy, see our DC BRRRR strategy guide.
Why the two-unit rowhome works in DC
A single-family rowhome in Petworth or Brookland often rents for less than it costs to finance at today’s rates. Adding a second legal unit changes the math in three ways:
- Combined rent rises by $1,800–$2,500 per month.
- Appraised value can rise, because two-unit comps and income support a higher number.
- Vacancy risk splits, since losing one tenant does not cut income to zero.
DC also exempts most small owners from rent control. Buildings owned by a natural person with four or fewer rental units qualify for an exemption, which keeps your rent-setting flexible. Our DC rent control investor guide explains how to claim it.
Step 1: Buy right — what to look for
Not every basement can become a legal unit. Screen every property with these checks before you make an offer.
| Check | What you want | Why it matters |
|---|---|---|
| Ceiling height | Close to code height, or room to lower the slab | Digging down costs $40,000–$90,000 |
| Separate entrance | Front or rear walk-out | Adding one needs an areaway and often public space approval |
| Zoning | A residential zone that allows two units by right | Some zones need a special exception |
| Water and sewer line | Recent camera scope | Old lines under the basement slab fail during a dig |
| Egress windows | Existing openings you can enlarge | New openings in a party-wall home need engineering |
| Historic district | Know before you plan exterior changes | Areaway and window changes may need review |
Our DC ADU and English basement financing page covers the permit path for the lower unit.
Step 2: Rehab budget for two units
A two-unit conversion is more than a finished basement. You are building a second home with its own kitchen, bath, electrical service, and fire separation.
Budget: 1,800 sq ft rowhome with 650 sq ft basement unit
| Category | Upper unit | Basement unit |
|---|---|---|
| Demo and haul-off | $9,000 | $8,000 |
| Structural (beams, underpinning if needed) | $6,000 | $25,000 |
| Electrical (new service, separate meter) | $14,000 | $12,000 |
| Plumbing | $12,000 | $14,000 |
| HVAC | $12,000 | $9,000 |
| Kitchen | $28,000 | $18,000 |
| Bathrooms | $22,000 | $12,000 |
| Fire separation and sound insulation | — | $9,000 |
| Egress windows and areaway | — | $11,000 |
| Floors, drywall, paint | $22,000 | $12,000 |
| Architect, engineer, permits | $10,000 | $8,000 |
| Contingency (15%) | $20,250 | $20,700 |
| Subtotal | $155,250 | $158,700 |
| Total rehab | $313,950 |
The basement often costs as much as the upper floors because of structural work, separation, and egress. That surprises many first-time DC investors. For how DOB and historic review add to the bill, read our DC rowhome rehab cost bands guide.
Step 3: Rent both units — building the rent roll
The DSCR refinance is sized on rent. Your goal is two signed leases at market rent before the appraiser visits.
| Unit | Layout | Monthly rent (example) |
|---|---|---|
| Upper (floors 1–2) | 3 bed, 2.5 bath | $3,900 |
| Basement | 1 bed, 1 bath | $2,150 |
| Combined | $6,050 |
Before you lease, complete these steps:
- Get a two-unit certificate of occupancy from DOB.
- Obtain a Basic Business License for rental housing for the property. See our DC rental BBL and registration guide.
- File the rent control exemption if you qualify.
- Use a lease that complies with DC tenant law. DC tenant protections are strong, so screen carefully.
Step 4: Refinance — sizing the DSCR loan
Here is where the deal proves itself. The appraiser uses two-unit comps and your leases. The lender checks whether rent covers the new payment.
Worked example: Petworth two-unit BRRRR
| Line | Amount |
|---|---|
| Purchase (single-family, dated) | $585,000 |
| Rehab (two units) | $313,950 |
| Hard money carry: 8 months at 10.99% | $52,400 |
| Closing costs (purchase) | $24,000 |
| All-in cost | $975,350 |
| Appraised value as two-unit | $1,225,000 |
| DSCR cash-out at 75% LTV | $918,750 |
| Cash left in the deal | ~$56,600 |
DSCR check on the new loan
| Item | Monthly |
|---|---|
| Combined rent | $6,050 |
| Principal and interest ($918,750 at 7.25%, 30 years) | $6,267 |
| Property tax (Class 1 at $0.85 per $100) | $868 |
| Insurance | $260 |
| Total payment (PITI) | $7,395 |
| DSCR | 0.82 |
A 0.82 ratio fails most programs. That is the most common mistake in DC BRRRR math: pulling the maximum cash-out instead of sizing to rent. Re-run the numbers at a lower loan amount.
| Loan amount | PITI | DSCR | Cash left in deal |
|---|---|---|---|
| $918,750 (75% LTV) | $7,395 | 0.82 | $56,600 |
| $780,000 | $6,449 | 0.94 | $195,350 |
| $700,000 | $5,903 | 1.02 | $275,350 |
At $700,000, DSCR clears 1.0 and the property carries itself. You leave more cash in the deal, but you own a performing two-unit asset with room to grow rent. Use our DSCR calculator to run your own rent and rate.
How rate and appraisal move the $700,000 loan
The $700,000 option clears 1.0 with little room. Two inputs can move it before you close: the rate you lock and the appraised value, which also sets the tax bill.
| Change | Monthly PITI | DSCR |
|---|---|---|
| Rate 6.75% | $5,668 | 1.07 |
| Rate 7.25% (base) | $5,903 | 1.02 |
| Rate 7.75% | $6,143 | 0.98 |
| Appraisal $1,150,000 (lower tax) | $5,850 | 1.03 |
| Appraisal $1,300,000 (higher tax) | $5,956 | 1.02 |
The rate matters far more than the appraisal. A half-point increase pushes this file below 1.0. At 7.25%, the largest loan that still hits 1.0 is about $721,500. To reach 1.10, the loan drops to about $641,000. Lock early, or size the loan to the higher rate you might get.
Zoning and occupancy rules for a DC flat
A two-unit rowhouse is called a flat under DC zoning. The rules decide whether your second rent is legal:
- RF-1 allows two units by right. The DC Office of Zoning’s RF rules permit two dwelling units in the main building, or one in the main building and one in an accessory building.
- A conversion needs a permit. DOB says converting a single dwelling into a two-family flat requires an approved permit.
- A flat needs a certificate of occupancy. Per DOB’s certificate of occupancy FAQs, residential buildings with two or more units need one. A single-family home does not.
- A third unit is a different project. Converting to three or more units in RF zones generally needs a special exception from the Board of Zoning Adjustment, plus 900 square feet of lot area per unit.
Confirm the zone on the DC zoning map before you pay for plans. An appraiser will look for the certificate of occupancy before counting the lower unit.
Levers that improve DC two-unit DSCR
If the ratio comes up short, work these levers before you give up on cash-out.
- Lease the basement furnished for mid-term stays. Traveling nurses and government contractors pay a premium. See mid-term rental financing in DC.
- Buy down the rate. Points reduce the payment and lift DSCR.
- Choose interest-only for part of the term, if the program allows it.
- Appeal the tax assessment if it jumped after rehab.
- Shop insurance with a carrier that writes small DC rentals.
Appraisal risks specific to DC two-unit rowhomes
| Risk | How to reduce it |
|---|---|
| Appraiser uses single-family comps only | Provide two-unit sales from the same ward |
| Basement valued as rec room | Show the certificate of occupancy and lease |
| Low ceiling height noted | Document the permit and final inspection |
| Rent comps below your lease | Provide three nearby basement leases |
| Unpermitted prior work | Close all open permits before ordering the appraisal |
Step 5: Repeat — scaling the strategy
Once your first two-unit rowhome is refinanced, the next file gets easier. You have a contractor who knows the basement process, an architect who knows DOB, and a leasing track record. Many DC operators run two or three conversions a year and later combine them into one portfolio refinance in Washington DC.
If you want to compare this plan against suburban BRRRR, our DC vs suburbs BRRRR guide runs the same math on Prince George’s County and Northern Virginia houses.
Two-unit BRRRR checklist
- Basement ceiling height and entrance verified before offer
- Zoning allows two units without a special exception
- Sewer line scoped
- Architect and engineer engaged before closing
- Rehab budget separates upper and lower units
- Two-unit certificate of occupancy and BBL issued
- Both units leased at market rent
- DSCR sized to rent, not maximum LTV
- Rent control exemption filed if eligible
Bottom line
A DC two-unit rowhome BRRRR can build real equity, but only when the basement is legal, the appraiser counts two units, and the loan is sized to rent. Buy with the conversion in mind, budget the basement as a full apartment, and let the DSCR ratio set your cash-out.
Start with a BRRRR scenario review or call (833) 264-7776. We fund the hard money purchase and rehab at 8.99%–13.5% and the DSCR refinance at 5.75%–10.5%.
Rates, terms and conditions offered only to qualified borrowers. Jaken Finance Group only finances non-owner occupied investment properties.