Office To Residential Conversion Calculator

Office-to-residential conversion is a major post-COVID real estate trend.

Office basis / SF

Building SF

Conversion / SF

Post-conversion units

Post-value per unit

Entitlement cost

Conversion uplift

$24,500,000

Total conversion cost

$75,500,000

Post-conversion value

$100,000,000

How the math works

Office basis = basis × SF. Total cost = basis + conversion SF + entitlement. Uplift = post − total.

$150 × 200k = $30M + $225 × 200k = $45M + $500k = $75.5M. 200 × $500k = $100M. Uplift $24.5M.

How to Use

Enter office building cost basis.
Enter conversion cost per sqft.
Enter post-conversion units.
Enter post-conversion value per unit.
Enter permit/entitlement cost.
Read conversion economics.

Frequently Asked Questions

Why office-to-residential?

Office vacancy at 15-25% in major markets (2023-2024). Residential in high demand. Older Class B/C office buildings often can't compete with new construction. Conversion unlocks value vs demolition. Cities like DC, Chicago, SF, Boston offer incentives. Key question: which buildings work? Pre-war buildings (small floorplates, operable windows): work. Post-war slabs (deep floorplates, sealed windows): don't work.

Which buildings convert?

Good candidates: pre-1960 construction, floorplate <20,000 SF, floor depth <35 ft, operable windows, residential-compatible MEP, favorable zoning. Bad candidates: post-1960 slab construction, deep floorplates (>50 ft), mechanical penthouse (hard to retrofit residential). Many trophy 1980s office: impossible to convert without gut renovation. Pre-war brick + timber often ideal. Historic district eligibility helps funding.

Conversion cost?

$150-350 PSF typical. Lower end: light conversion of small pre-war building with existing plumbing. Higher end: deep retrofit of modern slab building. Includes: new plumbing, new HVAC (per-unit), new electrical, unit partitioning, kitchen/bath fit-out, flooring, window replacement. Sometimes: facade/envelope upgrades, elevator replacement. Historic rehabs often trigger historic tax credit (20% federal + state credits). Can offset 20-40% of conversion cost.

Time and risk?

Conversion timeline: 18-30 months typical. Risks: zoning delays, structural issues uncovered in demo, window replacement complexity, environmental (asbestos/lead remediation), historic compliance. Budget 15-30% contingency. Conversion economics work when: residential $400-800/SF achievable, conversion cost <50% of achievable residential value, city incentives available. Not all office buildings pencil even in distressed markets.