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Calcimator

Affordable Housing Requirement Calculator

Calculate inclusionary housing units required for a development, affordable rent limits, density bonuses, and fee-in-lieu costs.

Inputs

$
years

Results

Required Affordable Units

15

Max Affordable Rent

$1,350.00

Market-Rate Units85
Total Units (with bonus)100
Density Bonus Units0
Max Housing Cost$1,500.00
Target Income$60,000.00
Total Fee In Lieu$0.00
Annual Revenue Gap$94,500.00
Three Bed3
How to Use This Calculator
  1. Enter Total Proposed Units, Inclusionary Rate, and Area Median Income for the jurisdiction.
  2. Select an AMI Target Level (30% Extremely Low up to 120% Workforce) and set the Affordability Period.
  3. Optionally add a Density Bonus, and choose Build On-Site Units or Pay Fee In Lieu (with Fee In Lieu per Unit if paying).
  4. Review Required Affordable Units and Max Affordable Rent (/mo).
  5. Use Market-Rate Units, Total Units (with bonus), and Annual Revenue Gap to inform your decision.

How the result changes with Total Proposed Units

Total Proposed UnitsRequired Affordable UnitsMax Affordable Rent
50576$1,350.00
1,753263$1,350.00
3,252488$1,350.00
4,501676$1,350.00

What each input means

Total Proposed Units
Total number of residential units in the proposed development.
Inclusionary Rate
Required percentage of units set aside as affordable. Typical range is 10-20%.
AMI Target Level
Target Area Median Income level for affordable units. Lower AMI = more affordable.
Area Median Income
HUD Area Median Income for the jurisdiction (household of 4).
Affordability Period
Duration the affordable units must remain income-restricted.
Density Bonus
Additional units allowed as incentive for providing affordable housing (varies by jurisdiction).
Compliance Method
Whether the developer will build affordable units or pay a fee to an affordable housing fund.
Fee In Lieu per Unit
Fee per required affordable unit if paying in lieu of construction.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Total Proposed Units = 100, Inclusionary Rate = 15, AMI Target Level = 80, Area Median Income = 75000 = 8 input(s) provided
  2. Calculate Required Affordable Units
    Required Affordable Units
    15 = 15
  3. Calculate Max Affordable Rent
    Max Affordable Rent
    1350 = $1,350
  4. Calculate Market-Rate Units
    Market-Rate Units = max(0
    85 = 85
  5. Calculate Total Units
    Total Units
    100 = 100

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators.

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