Commercial Real Estate Finance, Bifurcated Ground Leases & Leasehold Underwriting
Commercial Ground Lease CPI-Collared Reset & Coverage Formula
Calculate 99-Year Bifurcated Commercial Ground Lease CPI-Collared Periodic Rent Reset ($M), Residual Leasehold Net Operating Income ($M), Senior Ground-Rent Coverage Ratio, and Ground Rent % of Property NOI.
Bound 10-year ground-lease CPI escalations with MIN/MAX collars to protect leasehold equity!
In a bifurcated 99-year commercial ground lease, the fee-simple landowner enjoys a super-senior claim ahead of the leasehold mortgage lender—if the building operator defaults on ground rent, the landowner can wipe out the leasehold estate and take the building! Modern institutional ground leases replace volatile fair-market-value appraisal resets (which bankrupted several Manhattan office leaseholds) with 10-year CPI-Collared Escalations: Reset_Rent = Base_Ground_Rent * (1 + MIN(Cumulative_Cap, MAX(Cumulative_Floor, Cumulative_CPI_Growth)))! Leasehold lenders then verify Senior Ground-Rent Coverage = Pre_Ground_NOI / Reset_Ground_Rent (>= 3.5x–4.0x) and Ground Rent Share = Reset_Ground_Rent / Pre_Ground_NOI (<= 25%–30%)!
Verify on a Trophy Urban Multifamily Ground Lease—Base_Ground_Rent = $1.20M/yr (B2), Cumulative_10Yr_CPI = 0.28 (28.0% inflation surge, B3), Cumulative_10Yr_Floor = 0.10 (10.0%, B4), Cumulative_10Yr_Cap = 0.25 (25.0%, B5 -> Collared Reset Ground Rent = 1.20 * (1 + MIN(0.25, MAX(0.10, 0.28))) = $1.50M/yr in E2, saving $36k/yr vs uncapped CPI!), and Property_Pre_Ground_NOI = $6.00M/yr (B6): Leasehold NOI After Ground Rent is $4.50M/yr (E3), Senior Ground-Rent Coverage is 6.00 / 1.50 = 4.0000x (E4), and Ground Rent Share of NOI is 0.2500 (25.00% in E5)!
| Ground Lease Reset Metric ($1.2M Base, 28% CPI, 10%–25% Collar, $6.0M NOI) | Formula | Verified Output |
|---|---|---|
| Collared Reset Ground Rent ($M) | Base_Rent * (1 + MIN(Cap, MAX(Floor, CPI))) | $1.50M ($1.32M @ 4% CPI) |
| Leasehold Residual NOI ($M) | Pre_Ground_NOI - Reset_Ground_Rent | $4.50M ($4.68M @ 4% CPI) |
| Ground-Rent Coverage Ratio (x) | Pre_Ground_NOI / Reset_Ground_Rent | 4.0000x (4.5455x @ 4% CPI) |
| Ground Rent Share of NOI | Reset_Ground_Rent / Pre_Ground_NOI | 0.2500 (0.2200 @ 4% CPI) |
CPI-Collared Ground Rent & Coverage Ratio Formula
Validate Base_Rent > 0, CPI > -0.50, 0 <= Floor <= Cap < 2, and Pre_Ground_NOI > 0!
=LET(gr_0, B2, cp_i, B3, fl_r, B4, cp_m, B5, no_i, B6, IF(OR(gr_0 <= 0, cp_i <= -0.5, fl_r < 0, cp_m < fl_r, cp_m >= 2, no_i <= 0), "Invalid Ground-Lease Collar", LET(gr_1, gr_0 * (1 + MIN(cp_m, MAX(fl_r, cp_i))), ROUND(no_i / gr_1, 4))))Disinflation Floor Activation Check (Set 10-Year Cumulative CPI = 4.0%)
Drop Cumulative_10Yr_CPI B3 to 0.04 (below the 10.0% floor): MAX(0.10, 0.04) activates the landowner’s 10% minimum floor so Reset Ground Rent E2 steps up to $1.32M/yr, leaving $4.68M Leasehold NOI (E3) at 4.5455x coverage (E4)!
=IF(ISTEXT(E4), E4, ROUND((B2 * (1 + MIN(B5, MAX(B4, B3)))) / B6, 4))Try the example
Use the original values or change them to test your understanding.