Determining Building Area Flashcards
Building Efficiencies & Space Requirements
Overall Bldg Efficiency Or (Efficiency Ratio)
(Net Assignable Area / Gross Area) or (net assignable areas / net assignable area + non assignable areas)
What is excluded in Net Area
Net area does not include corridors or space for general circulation between rooms, mechanical rooms, stairways, elevators and mechanical shafts, building Core, restrooms (spaces that do not directly house the primary activities of the building)
Base Bldg Efficiency
Usable Area / Gross Area
What is excluded in Usable Area
Usable Area only pertains to tenant used areas & “secondary circulation” (circulation that is only used for one particular tenant)
List in order from Least to Greatest Areas taken of space: (Rentable Area, Gross Area, Usable Area, Net Area)
Net Area, Usable Area, Rentable Area, Gross Area
Space Type Common Efficiency Ratios:
a. Office
b. Retail Offices
c. Restaurants
d. public libraries
e. museums
f. theaters
g. hospitals
Efficiency Ratios
a. Office = .75 - .85%
b. Retail Offices = .75 - .90%
c. Restaurants = 0.65 - 0.70%
d. Libraries = .75 - .80%
e. Museums = .83 - .90%
f. Theaters = .60 - .75%
g. Hospitals = .50-.65%
List in order of efficiency: (Hospital, Museum, Theater, Restaurant, Library, Office)
Hospital, Theater, Restaurant, Library, Museum Office
Typical Space Requirements:
a. Mechanical Rooms
b. Vertical dust Space
c. Toilets
a. Mech Room = 5-9% (say 9%)
b. Vertical Dust Space (3-4 SF per 1000 SF)
c. 50 SF per Water Closet
Toilet Requirements per plumbing Code
1 per 15 people up to 55, 1 per 40 people over 55 occupants
Rentable Area vs Usable Area
Rentable area includes circulation and service spaces. In a leased office, retail, residential or industrial building, the building owner bases rents on the sum of 2 areas ( the tenant’s occupant area + the pro-rated share of areas of the building used by all tenants)
What is unique about Rentable Area
Rentable Area = Occupant area x Load Factor
