How Tabulation Metrics Are Calculated
Shared Tabulation Explanation
|
Metric |
Formul a |
Notes |
|---|---|---|
|
Acreage |
Site area within the property line |
Denominator for FAR and DU/AC |
|
FAR (Floor Area Ratio) |
Gross SF ÷ Site Area |
TestFit's headline density metric |
|
Efficiency (EFF%) |
NRSF ÷ Gross SF |
Also read as the gross-to-net ratio |
|
NRSF / NRM |
Total Unit Area + Balcony (only if balconies are toggled on) |
Net rentable area |
|
COMMON |
Corridor area, including the run-up to stairs/lifts |
|
|
STAIR |
Staircase area |
|
|
LIFTS |
Elevator area |
|
|
AMENITY |
Area assigned to amenity spaces |
Default designation for amenity program |
|
BOH (Back of House) |
Reserved area category |
Documented by TestFit as "not yet implemented" — currently always zero |
|
UNALLOCATED |
Gross area that isn't NRSF, Common, Stair, Lifts, or Amenity |
Space the solver couldn't assign to a category — see Caveats |
|
Gross Conditioned SF |
NRSF + COMMON + STAIR + LIFTS + AMENITY + BOH |
All conditioned (air-conditioned) building area |
|
EXTERNAL |
Garage Gross Area + Balcony Area |
|
|
GROSS SF |
Gross Conditioned SF + EXTERNAL |
The numerator TestFit uses for FAR |
|
DU/AC (DU/HA) |
Total Dwelling Units ÷ Site Acreage (or Hectares) |
|
|
AVG (unit size) |
Gross Conditioned SF of units ÷ Unit Count |
|
|
AVG (parking) |
Total Garage Area ÷ Total Stalls |
|
|
Parking Ratio |
Total Stalls ÷ Total Units |
|
|
Bldg CVG% / Imp CVG% |
Building Footprint (or Impervious Area) ÷ Site Area |
Coverage percentages |
Data Center Tabulation
|
Parameter |
Definition |
How it's derived |
|---|---|---|
|
Electrical Availability (MVA) |
Mega-Volt-Amps available to use on site |
Entered directly as a site input, reflecting utility/interconnect capacity |
|
Electric Efficiency |
Usable MVA from the site |
The share of nameplate MVA that's actually usable capacity |
|
(MW) Power Per Bay |
Available power allocated to each bay |
One of two ways to define IT power (see below) — the "Use Per-Bay Power" method |
|
Target Power Density |
MW (or kW) of IT power per unit of Data Hall area |
The alternate way to define IT power; a rate applied across Data Hall area |
|
Design PUE (Power Usage Effectiveness) |
Total Facility Power ÷ Critical (IT) Power |
Set by the designer; TestFit uses it to back into non-IT power |
|
Critical (IT) Power |
Power delivered to compute equipment |
= Power Per Bay × bay count, or Target Power Density × Data Hall area, depending on method |
|
Non-IT (overhead) Power |
Power spent on cooling, electrical losses, and other facility overhead |
= Total Facility Power − Critical Power, where Total Facility Power = Design PUE × Critical Power |