Determining Occupant Load & Egress Capacity

Flad Architects of 5 Flad Code Forum Notes : 30 July 2015

Flad Code Forum Notes 30 July 2015 1. Code Forums

a. Notes of past code forums are posted at : i. Flad Home Page / Resources / Codes / Forums / Year / Date of Forum.

b. This Code Forum will Discuss : Determining Occupant Load & Egress Capacity c. Additional information is contained in attached PowerPoint slides: PP-pages.

Determining Occupant Load & Egress Capacity – Refer to PP-1 through PP-58 2. References

a. International Building Code - 2012 edition = IBC b. NFPA 101 Life Safety Code - 2012 edition = LSC

3. Occupancy Classification vs. Function of Space/Use (PP-3) a. Occupancy Classifications are general in their application as their scope focuses on the

entire building. This affects the general building limitations (allowable area & allowable stories), construction type, the means of egress as it pertains to distance (travel distances, common path of egress, dead-end), fire protection systems, interior finishes, and the number of plumbing fixtures.

b. Functions of space/use are specific to rooms and spaces. This affects occupant load (by room, by story and for the entire building), the means of egress as it pertains to capacity (width of egress components and number of means of egress), miscellaneous life safety components (visible signals, occupant notifications, and emergency lighting), fire alarm requirements, and the number of plumbing fixtures.

4. Occupancy Classification (PP4 - PP11) a. IBC : structures or portions of structures shall be classified with respect to occupancy in

one or more of the groups listed in this section : i. Assembly (A-1, A-2, A-3, A-4, A-5) ii. Business (B) iii. Educational (E) iv. Factory and Industrial (F-1 & F-2) v. High Hazard (H-1, H-2, H-3, H-4, H-5) vi. Institutional (I-1, I-2, I-3, I-4) vii. Mercantile (M) viii. Residential (R-1, R-2, R-3, R-4) ix. Storage (S-1 & S-2) x. Utility and Miscellaneous (U)

b. LSC : The purpose for which a building or other structure, or part thereof, is used or intended to be used (3.3.188 Occupancy) i. Ambulatory Health Care (New/Exist) ii. Apartment Buildings (New/Exist) iii. Assembly (New/Exist) iv. Business (New/Exist) v. Day-Care (New/Exist) vi. Detention and Correctional (New/Exist) vii. Education (New/Exist) viii. Industrial ix. Health Care (New/Exist) x. Hotels and Dormitories (New/Exist) xi. Mercantile (New/Exist) xii. One- and Two-Family Dwellings


xiii. Residential Board and Care (New/Exist) xiv. Storage

c. Example : Flad HQ = Business (IBC), Existing Business (LSC) d. Q1 : Why classify buildings into groups? (PP12 - PP13)

i. A1 : (1) IBC

(a) It assigns an acceptable level of risk against the damages of fire respective to a particular occupancy group by limiting the building's height and area according to the building's construction type.

(b) It organizes occupancies with similar fire hazard and life safety properties into groups so that code provisions for that group can lessen the associated risks.

(2) LSC (a) It reflects the design features, usage patterns, and unique life safety needs

of the occupants. 5. Occupant Load : Function of Space (PP14 - PP17)

a. The occupant load (OL) is to reflect the maximum number of people anticipated to occupy the building at any given time and under all probable situations i. IBC : OCCUPANT LOAD. The number of persons for which the means of egress of

a building or portion thereof is designed. ii. LSC : 3.3.162.2 Occupant Load. The total number of persons that might occupy a

building or portion thereof at any one time. b. Code References

i. IBC : Table 1004.1.2 Maximum Floor Area Allowances Per Occupant ii. LSC : Table 7.3.1.2 Occupant Load Factor

6. Gross Floor Area (GFA) vs. Net Floor Area (NFA) (PP18 - PP19) a. GFA : The floor area within the inside perimeter of the exterior walls of the building

under consideration, exclusive of vent shafts and courts, without deduction for corridors, stairways, closets, the thickness of interior walls, columns or other features. The floor area of a building, or portion thereof, not provided with surrounding exterior walls shall be the usable area under the horizontal projection of the roof or floor above. The gross floor area shall not include shafts with no openings or interior courts.

b. NFA : The actual occupied area not including unoccupied accessory areas such as corridors, stairways, toilet rooms, mechanical rooms and closets

7. Function of Space (IBC) vs. Use (LSC) : Differences a. IBC : Table 1004.1.2

i. Organized alphabetically ii. Differences (More Restrictive)

(1) Kitchens = 200 gross (2) Dormitories = 200 gross (3) Galleries = 30 net (4) Pool – Decks = 15 gross (5) Storage areas = 300 gross (6) Warehouses= 500 gross (7) Manufacturing/Hazard = 200 gross

iii. In IBC, Not in LSC (1) Agricultural Building, (2) Airport Hangars (3) Assembly

(a) Exhibit Gallery/Museum (b) Fixed Seats (benches) (c) Standing (d) Outside Areas (e) Standing Space


iv. Bowling Centers v. Courtrooms (No fixed seating) vi. Dormitories vii. Mechanical viii. Parking Garages

b. LSC : Table 7.3.1.2 i. Organized by Occupant Classifications ii. Differences (More Restrictive)

(1) Kitchens = 100 gross (2) Dormitories = 50 gross (3) Galleries = 100 net (4) Pool – Decks = 30 gross (5) Storage areas = 500 gross (6) Storage (not in S or M) = 500 gross (7) Manufacturing/Hazard (Industrial) = 100 gross

iii. In LSC, Not in IBC (1) Air Traffic Control Tower (2) Assembly – Waiting Spaces (Theatre) (3) Detention & Correctional (4) Exercise Rooms (w/o equipment) (5) Locker Rooms (6) Merc – sales area on 2 or more street floors (7) Swimming Pools - Decks (8) Stages – Catwalks/Galleries

8. Occupant Load Spreadsheet (PP21 - PP22) a. Excel Spreadsheet b. Combines IBC’s “functions of use” and LSC’s “use” c. Alphabetical d. Calculates e. Occupant Loads by level f. Egress Widths by level g. How to Use?

i. Assign “Functions of Spaces” to floor plans ii. Transfer areas from plan into “B – Area” column iii. Determine “Egress Width” multiplier(s) iv. The spreadsheet calculates the rest

9. Determining Egress Capacity (PP23 - PP30) a. (3) Means of Egress (MOE) components

i. Exit Access - doors & gates, corridors & aisles, stairways, ramps, egress balconies ii. Exits - doors, stairways, exit passageways, ramps, horizontal exits iii. Exit Discharge - doors, access to a “public way” (sidewalks, egress courts, stairs,

ramps, yards), dispersal areas b. Means of Egress Sizing

i. 1005.2 Minimum width based on component. The minimum width, in inches (mm), of any means of egress components shall not be less than that specified for such component, elsewhere in this code. (1) Example

(a) Occupant load determines a stair must be 40” wide (b) Section 1009 Stairways : 44” minimum (see exceptions) (c) 44” governs (more restrictive)

ii. 1005.3.1 Stairways = 0.3” per occupant (1) Exceptions 0.2” per occupant IF all

(a) Sprinkled (throughout)


(b) Emergency voice/alarm communication system (c) Not Group H or I-2 (hospital, nursing home, etc)

(2) Minimum stairway width = 44” (a) 44” / (0.3”/occupant) = 146.6 (round down) = 146 occupants (b) 44” / (0.2”/occupant) = 220 occupants

iii. Minimum Corridor Width (1) IBC : Table 1018.2 (2) LSC : Occupant Chapters

(a) 36” (Exit Access) : New (b) 28” (Exit Access) : Exist (c) 44” : New Assembly serving 50 or more and New/Exist Ambulatory (d) 72”: Existing Education (e) 96” : New Health Care : housing, treatment or use of impatients

iv. Minimum Door Widths (1) IBC : 1008.1.1 Size of doors. The minimum width of each door opening shall L

provide a clear width of 32”. (a) Exceptions:

(i) 41.5”: Group I-2 (ii) 28”: Resident sleeping units in Group I-3 (iii) No minimum width

1) Storage closets (<10 sf) 2) Revolving Doors 3) Group R-2 and R-3 4) Dwelling/Sleeping Units

(2) LSC : 7.2.1.2.3 Minimum Door Leaf Width. (a) 7.2.1.2.3.2 Door openings in means of egress shall be not less than 32” in

clear width L (i) Exceptions:

1) 24” door leaf width : Exit access door assemblies serving a room not exceeding 70 sf and not required to be accessible

2) 28” door leaf width : Door openings serving a building not required to be accessible to persons with severe mobility impairments & existing buildings

3) 28” clear width : Resident sleeping rooms 4) No requirements : Detention & Correctional occupancies (28” (new) &

19” (exist) for resident sleeping rooms), power-operated door leaf in a 2-leaf opening, revolving doors, and 56” Minimum Stairway : Door (sole exit discharge) = 2/3 stairway width

(ii) 41.5” : New Health Care (iii) 34” & 28” (corridor doors w/no evacuation) : Existing Health Care

10. Determining Occupant Load - Example : Flad HQ (PP31 - PP55) a. Programming

i. 60,000 sf, Office building ii. Occupancy Classification = Business iii. Applicable Code(s) = IBC (2012) iv. OL = 60K/100 sf per occupant = 600 occupants v. Number of Exits = (3)

(1) OL >500 but <1000, requires (3) Exits IF (1) Story b. Schematic Design

i. Occupancy Classification = Business ii. 55,152 sf, Office building

(1) 18580 sf (Ground) + 18876 sf (1st) + 18696 sf (2nd) iii. OL = 562 occupants


(1) 186 occ (Ground) + 189 occ (1st) + 187 occ (2nd) iv. (3) Stories

(1) (2) Exits per story required c. Design Development

i. OL = 562 occupants if “business use” only (100 sf/occ) ii. OL = 869 occupants per varied functions of use

(1) Reduces OL : (a) Storage – Not mercantile (500 sf/occ) (b) Mechanical shafts (c) Open to below

(2) Increases OL (a) Assembly – Unconcentrated (15 sf/occ) (b) Classroom Area (20 sf/occ) (c) Locker Rooms (50 sf/occ)

(3) Same OL (a) Stacks (100 sf/occ)

iii. Site Plan Change = Code Change (1) Existing Design : all stairs exit at Ground Level

(a) The floor requiring the greatest egress capacity dictates the minimum stair width from that floor down to the Exit Discharge

(b) Greatest egress capacity = 87 occupants (2) New Design : Sloping site = different Exit Discharges

(a) (1) stair (east) exits at Ground Level (b) (1) stair (center) exits at 1st Level (c) (1) stair (west) exits between Ground & 1st Levels

(3) IBC : 1005.6 Egress convergence. Where the means of egress from stories above and below converge at an intermediate level, the capacity of the means of egress from the point of convergence shall not be less than the sum of the required capacities for the two adjacent stories.

(4) Stair (West & Center) = 81 + 123 = 204 converging occupants (5) 204 converging occupants x 0.3”/occ = 61.2” for exit discharge doors

11. Occupant Load Determination Process (PP56 - PP55) a. Option 1 (PDF + Excel)

i. Print-to-PDF floor plans ii. Determine Function of Use areas iii. Input areas into Occupant Load spreadsheet iv. Input Egress Width multiplier(s) v. Determine Occupant Load (OL) by level vi. Create an OL diagram indicating OL on each level vii. Verify stairways and other egress components widths meet the minimum

requirements b. Option 2 (BIM)

i. Create Area Plans in Revit ii. Set Up Parameters iii. Create a Key Schedule iv. Create an Occupancy Schedule v. Tag the OL Area Plan vi. Con : Need to manually enter area “values” in schedule to get them to tag on the

plan since shared and calculated value parameters cannot be used in a tag.

F L A D C O D E F O R U M

Determining Occupant Load and

Egress Capacity

07/30/2015 Flad Code Forum 1

O U T L I N E

• Occupancy Classification vs. Function of Use

• Occupancy Classification

– IBC vs. LSC : Similarities and Differences

• Function of Use• Function of Use

– IBC vs. LSC : Similarities and Differences

• Determining Egress Capacity

– Stairways and Other Egress Components

• Example : By Phase

– Programming-SD-DD-CD


Occupancy Classification

vs. Function of Space / Use• Occupancy Classifications

– General

– Scope : entire building

– Affects• General bldg limitations

– Allowable area

– Allowable stories

• Function of Space / Use– Specific

– Scope : rooms & spaces

– Affects• Occupant Load

– By room

– By story– Allowable stories

– Construction Type

• Means of Egress - Distance– Travel Distances

– Common Path of Egress

– Dead-End

• Fire Protection Systems

• Interior Finishes

• # of Plumbing Fixtures

– By story

– Entire bldg

• Means of Egress - Capacity– Width

– Number

• Misc LS components– Visible signals (LSC)

– Occupant Notifications

– Emergency lighting

– Fire Alarm

• # of Plumbing Fixtures


Occupancy Classifications

• IBC (10)

– Assembly

– Business

– Educational

– Factory and Industrial

– High Hazard

– Institutional

• LSC (14)

– Ambulatory Health Care

– Apartment Buildings

– Assembly

– Business

– Day-Care

– Detention and Correctional – Institutional

– Mercantile

– Residential

– Storage

– Utility and Miscellaneous

– Detention and Correctional

– Education

– Industrial

– Health Care

– Hotels and Dormitories

– Mercantile

– One- and Two-Family Dwellings

– Residential Board and Care

– Storage

Flad Code Forum07/30/2015 4


• IBC

– Assembly

– Business

– Educational

– Factory and Industrial

• LSC

– Assembly

– Business

• Ambulatory Health Care

– Education

• Day-Care

– “Factory and Industrial”

• Industrial

– No Hazard– High Hazard

– Institutional

– Mercantile

– Residential

– Storage

– Utility and Miscellaneous

– No Hazard

– “Institutional”

• Day-Care

• Detention and Correctional

• Health Care

– Mercantile

– Residential

• Apartment Buildings

• Hotels and Dormitories

• One- and Two-Family Dwellings

• Residential Board and Care

– Storage

– No Utility and Miscellaneous


Occupancy Classifications (IBC)

• Assembly

– A-1 (Theatres)

– A-2 (Restaurants)

– A-3 (Libraries)

– A-4 (Kohl Center)

– A-5 (Randall Stadium)

• Business (B)

– Professional or service-type transactions (Flad

• Institutional

– I-1 (Assisted Living)

– I-2 (Hospitals)

– I-3 (Correctional Facilities)

– I-4 (Adult/Child Day Care)

• Mercantile (M)

• Residential

– R-1 (Hotels)– Professional or service-type transactions (Flad

Architects)

– Ambulatory Care Facilities

• Educational (E)

• Factory and Industrial

– F-1 (Moderate Hazard)

– F-2 (Low Hazard)

• High Hazard

– H-1 (Detonation)

– H-2 (Deflagration )

– H-3 (Supports combustion)

– H-4 (Health Hazards)

– H-5 (Semiconductor)

– R-1 (Hotels)

– R-2 (Apartments)

– R-3 (Catch all)

– R-4 (Assisted Living)

• Storage

– S-1 (Moderate Hazard)

– S-2 (Low Hazard)

• Utility and Miscellaneous (U)



• IBC (26)

– Assembly (A-1, A-2, A-3, A-4, A-5)

– Business (B)

– Educational (E)

– Factory and Industrial (F-1 & F-2)

– High Hazard (H-1, H-2, H-3, H-4, H-5)

• LSC (14)

– Ambulatory Health Care

– Apartment Buildings

– Assembly

– Business

– Day-Care


– Institutional (I-1, I-2, I-3, I-4)

– Mercantile (M)

– Residential (R-1, R-2, R-3, R-4)

– Storage (S-1 & S-2)

– Utility and Miscellaneous (U)


– Education

– Industrial

– Health Care

– Hotels and Dormitories

– Mercantile


– Residential Board and Care

– Storage



• IBC (26)

– Assembly (A-1, A-2, A-3, A-4, A-5)

– Business (B)

– Educational (E)



• LSC (25)

– Ambulatory Health Care (New/Exist)

– Apartment Buildings (New/Exist)

– Assembly (New/Exist)

– Business (New/Exist)

– Day-Care (New/Exist)

– Detention and Correctional (New/Exist)


– Mercantile (M)





– Education (New/Exist)

– Industrial

– Health Care (New/Exist)

– Hotels and Dormitories (New/Exist)

– Mercantile (New/Exist)


– Residential Board and Care (New/Exist)

– Storage


Occupancy Classifications (LSC)

• Ambulatory Health Care (N/E)

• Apartment Buildings (N/E)

• Assembly (N/E)

– < 300

– > 300 < 1000

– > 1000

• Business (N/E)

• Health Care (N/E)

• Hotels and Dormitories (N/E)

• Mercantile (N/E)

– Regular

– Mall

– Bulk Retail

• One- and Two-Family Dwellings• Business (N/E)

• Day-Care (N/E)

– > 12 Clients

– Day Care Homes

• Detention and Correctional (N/E)

• Education (N/E)

• Industrial

– General Purpose

– Special Purpose

– High hazard

• One- and Two-Family Dwellings

• Residential Board and Care (N/E)

– Small

– Large

• Storage– Low & Ordinary Hazard

– High Hazard



• IBC (26)

– Assembly (A-1, A-2, A-3, A-4, A-5)

– Business (B)

– Educational (E)



• LSC (37)



– Assembly (New/Exist) x3


– Day-Care (New/Exist) x2



– Mercantile (M)






– Industrial x3



– Mercantile (New/Exist) x3


– Residential Board and Care (New/Exist) x2

– Storage x3



• IBC (27)

– Assembly (A-1, A-2, A-3, A-4, A-5)

– Business (B)

– Educational (E)



• LSC (37)



– Assembly (New/Exist) x3


– Day-Care (New/Exist) x2



– Mercantile (M)




– Existing Buildings (Chapter 34)



– Industrial x3



– Mercantile (New/Exist) x3


– Residential Board and Care (New/Exist) x2

– Storage x3


Occupancy Classifications Occupancy MUST match its intended purpose


Assembly A-3 : Place of Religious Worship?

Assembly A-2 : Nightclub


• EXAMPLE : Cancer Center (CC) was initially designated as an I-2 (IBC) and as a New

Health Care occupancy (LSC) by the Design Team because the hospital that was

partnered with the CC wanted the future flexibility of “converting” it to be part of

the hospital.

• The Cancer Center did not meet the definitions of a Institutional/HC occupancy :

– IBC : 308.4 Institutional Group I-2.

• This occupancy shall include buildings and structures used for medical care on a 24-hour basis

for more than five persons who are incapable of self-preservation.

– LSC : 3.3.188.7* Health Care Occupancy. An occupancy used to provide medical

or other treatment or care simultaneously to four or more patients on an

inpatient basis, where such patients are mostly incapable of self-preservation

due to age, physical or mental disability, or because of security measures not

under the occupants' control.

• SOLUTION : Design the building to meet the more stringent I-2/New HC

requirements (Construction Type, Means of Egress, etc.) but designate its

occupancy classification as Group B – Business (IBC) & New Business (LSC).


Occupant Load : Function of Space

• The occupant load (OL) is to reflect the maximum number of people anticipated to occupy the building at any given time and under all probable situations

– IBC : OCCUPANT LOAD. The number of persons for which the means of egress of a building or portion thereof is designed.

– LSC : 3.3.162.2 Occupant Load. The total number of persons that might occupy a building or portion thereof at anyone time.



You don’t build a church for Easter Sunday …


… but you design the egress components for it.


• IBC : Table 1004.1.2

Maximum Floor Area

Allowances Per

Occupant

• LSC : Table 7.3.1.2

Occupant Load Factor


Determining Occupant Load (OL)

• Description of Space

– IBC : “Function of Use”

– LSC : “Use”

• Occupant Load Factor

– Max area per Occupant

– Gross vs. Net?


Floor Areas - Gross vs. Net

• Gross Floor Area (GFA)– The floor area within the inside perimeter of the exterior walls

of the building under consideration, exclusive of vent shafts and courts, without deduction for corridors, stairways, closets, the thickness of interior walls, columns or other features.

– The floor area of a building, or portion thereof, not provided with surrounding exterior walls shall be the usable area under The floor area of a building, or portion thereof, not provided with surrounding exterior walls shall be the usable area under the horizontal projection of the roof or floor above. The gross floor area shall not include shafts with no openings or interior courts.

• Net Floor Area (NFA) – The actual occupied area not including unoccupied accessory

areas such as corridors, stairways, toilet rooms, mechanical rooms and closets


IBC vs. LSC : Differences

• IBC : Table 1004.1.2– Organized alphabetically

– Differences (More Restrictive)• Kitchens = 200 gross

• Dormitories = 200 gross

• Galleries = 30 net

• Pool – Decks = 15 gross

• Storage areas = 300 gross

• Warehouses= 500 gross

• Manufacturing/Hazard = 200 gross

– In IBC, Not in LSC

• LSC : Table 7.3.1.2– Organized by Occupant Classifications

– Differences (More Restrictive)• Kitchens = 100 gross

• Dormitories = 50 gross

• Galleries = 100 net

• Pool – Decks = 30 gross

• Storage areas = 500 gross

• Storage (not in S or M) = 500 gross

• Manuf/Hazard (Industrial) = 100 gross

– In LSC, Not in IBC– In IBC, Not in LSC• Agricultural Building

• Airport Hangars

• Assembly – Exhibit Gallery/Museum

– Fixed Seats (benches)

– Standing

– Outside Areas

– Standing Space

• Bowling Centers

• Courtrooms (No fixed seating)

• Dormitories

• Mechanical

• Parking Garages

– In LSC, Not in IBC• Air Traffic Control Tower

• Assembly – Waiting Spaces (Theatre)

• Detention & Correctional

• Exercise Rooms (w/o equipment)

• Locker Rooms

• Merc – sales area on 2 or more street floors

• Swimming Pools - Decks

• Stages – Catwalks/Galleries


OL Spreadsheet

• Excel Spreadsheet

• Combines IBC’s

“functions of use” and

LSC’s “use” LSC’s “use”

• Alphabetical

• Calculates

– Occupant Loads by level

– Egress Widths by level

• How to Use?


1. Assign “Functions of Spaces” to floor plans

2. Transfer SF from plan into “B – Area” column

3. Determine “Egress Width” multiplier(s)

4. The spreadsheet calculates the rest


Determining Egress Capacity

• (3) Means of Egress (MOE) components– Exit Access

• Doors & Gates

• Corridors & Aisles

• Stairways, Ramps, Egress Balconies

Exits– Exits• Doors, Stairways, Exit Passageways, Ramps, Horizontal Exits

– Exit Discharge• Doors

• Access to a “Public Way”– Sidewalks, egress courts, stairs, ramps, yards

• Dispersal Areas


Determining Egress Capacity (IBC)

• Section 1005 Means of Egress Sizing

– 1005.2 Minimum width based on component.

The minimum width, in inches (mm), of any means of

egress components shall not be less than that

specified for such component, elsewhere in this code.specified for such component, elsewhere in this code.

– Example

• Occupant load determines a stair must be 40” wide

• Section 1009 Stairways : 44” minimum (see exceptions)

• 44” governs (more restrictive)




– 1005.3

• 1005.3.1 Stairways = 0.3” per occupant

– Exceptions 0.2” per occupant IF all

» Sprinkled (throughout)» Sprinkled (throughout)

» Emergency voice/alarm communication system

» Not Group H or I-2 (hospital, nursing home, etc)

– Minimum stairway width = 44”

• 44” / (0.3”/occupant) = 146.6 (round down) = 146 occupants

• 44” / (0.2”/occupant) = 220 occupants




– 1005.3

• 1005.3.2 Other egress components = 0.2” per occupant

– Exceptions 0.15” per occupant IF all

» Sprinkled (throughout)» Sprinkled (throughout)

» Emergency voice/alarm communication system

» not Group H or I-2 (Hospitals, nursing home, etc)

– Minimum clear door width = 32”

• 32” / (0.2”/occupant) = 160 occupants

• 32” / (0.15”/occupant) = 213.3 (round dn) = 213 occupants


Determining Egress Capacity (LSC)

• 7.3.3 Egress Capacity : more stringent than IBC


Minimum Corridor Width

• IBC : Table 1018.2 • LSC : Occupant Chapters

– 36” (Exit Access) : New

– 28” (Exit Access) : Exist

– 44”

• New Assembly

– Serving 50 or more

• New/Exist Ambulatory

– 72”: Existing Education

– 96” : New Health Care

• Housing, treatment or use

of impatients


IBC : Minimum Door Widths

• 1008.1.1 Size of doors. The minimum width of each door opening shall … provide a clear width of 32”.

– Exceptions:Exceptions:

• 41.5”: Group I-2

• 28”: Resident sleeping units in Group I-3

• No minimum width

– Storage closets (<10 sf) :

– Revolving Doors

– Group R-2 and R-3

– Dwelling/Sleeping Units


LSC : Minimum Door Widths

• 7.2.1.2.3 Minimum Door Leaf Width. – 7.2.1.2.3.2 Door openings in means of egress shall be not less than 32” in clear

width …

– Exceptions:• 24” door leaf width : Exit access door assemblies serving a room not exceeding 70 sf and

not required to be accessible

• 28” door leaf width : – Door openings serving a building not required to be accessible to persons with severe mobility – Door openings serving a building not required to be accessible to persons with severe mobility

impairments

– Existing buildings

• 28” clear width : Resident sleeping rooms

• No requirements : – Detention & Correctional occupancies

» 28” (new) & 19” (exist) for resident sleeping rooms

– Power-operated door leaf in a 2-leaf opening

– Revolving doors

– 56” Minimum Stairway : Door (sole exit discharge) = 2/3 stairway width

– 41.5” : New Health Care

– 34” & 28” (corridor doors w/no evacuation) : Existing Health Care



• Programming

• Schematic Design

• Design Development

• Construction Documents




• Programming

– 60,000 sf, Office building

– Occupancy Classification = Business

– Applicable Code(s) = IBC (2012)

– OL = 60K/100 sf per occupant = 600 occupants


– OL = 60K/100 sf per occupant = 600 occupants

• Number of Exits = (3)

– OL >500 but <1000, requires (3) Exits IF (1) Story





• Programming

• Schematic Design– Occupancy Classification = Business

– 55,152 sf, Office building• 18580 sf (Ground) + 18876 sf (1st) + 18696 sf (2nd)


• 18580 sf (Ground) + 18876 sf (1st) + 18696 sf (2nd)

– OL = 562 occupants• 186 occ (Ground) + 189 occ (1st) + 187 occ (2nd)

– (3) Stories• (2) Exits per story required




• Programming



– OL = 562 occupants


– OL = 562 occupants

• 187 – 2nd

• 189 – 1st

• 186 - Ground


Determining MOE Capacity

• OL = 562 occupants : 187 occupants (2nd)



• OL = 562 occupants : 189 occupants (1st)



• OL = 562 occupants : 186 occupants (Ground)



• Programming


• Design Development– OL = 562 occupants if “business use” only (100 sf/occ)

– OL = 869 occupants per varied functions of use• Reduces OL :


• Reduces OL : – Storage – Not mercantile (500 sf/occ)

– Mechanical shafts

– Open to below

• Increases OL– Assembly – Unconcentrated (15 sf/occ)

– Classroom Area (20 sf/occ)

– Locker Rooms (50 sf/occ)

• Same OL– Stacks (100 sf/occ)


• OL = 869 occupants– 259 occupants (2nd)

• Means of Egress required = 2 (doesn’t meet (1), <500 occ)

• MOE Capacity– Stairways =

» (259 occupants)/(3 stairs) = 86.3 = 87 occupants per stair



» 87 occupants x 0.3”/occupant = 26.1” each stair width

» 26.1” < 44” minimum stair width = 44”

– Other egress components = (259) x 0.2 = 51.8” total width

» Corridors

• (1) Corridor = 51.8” > 36” minimum = 51.8”

» Exit Doors (@ stairways)

• (3) stairways = 17.3” each < 32” minimum = 32”


• OL = 869 occupants : 259 occupants (2nd)



• OL = 869 occupants– 241 occupants (1st)









» Corridors





• OL = 869 occupants : 241 occupants (1st)



• OL = 869 occupants– 369 occupants (Ground)



» (369 occupants)/(3 stairs) = 123 occupants per stair


» (369 occupants)/(3 stairs) = 123 occupants per stair




» Corridors




» Exit Discharge Doors

• (3) ED doors = 24.6” each < 32” minimum = 32”


• OL = 869 occupants : 369 occupants (Ground)


OL SUMMARY = 869 Total

• Ground

• 369 occupants

• # of MOE = 2

• Stairways = 44”

• Other egress

• 1st

• 241 occupants

• # of MOE = 2


• Other egress

• 2nd

• 259 occupants

• # of MOE = 2


• Other egress • Other egress

components

– Corridors = 73.8”

– Exit Doors = 32”


• Other egress

components



• Other egress

components



Code Issue : Corridor Width

• OL requires (1) corridor to be 73.8” : Solution?

• Add a north corridor … connected to south corridor


Site Plan Change = Code Change

• Existing Design : all stairs exit at Ground Level

– The floor requiring the greatest egress capacity

dictates the minimum stair width from that floor

down to the Exit Dischargedown to the Exit Discharge

• Greatest egress capacity = 87 occupants


Site Plan Change = Code Change

• NEW Design : Sloping site = different Exit Discharges

– (1) stair (east) exits at Ground Level

– (1) stair (center) exits at 1st Level

– (1) stair (west) exits between Ground & 1st Levels

• Convergence : re-evaluate stair egress loads


Egress Convergence

• IBC : 1005.6 Egress convergence.

Where the means of egress from stories above and below

converge at an intermediate level, the capacity of the means

of egress from the point of convergence shall not be less than

the sum of the required capacities for the two adjacent the sum of the required capacities for the two adjacent

stories.

– Stair (West & Center) = 81 + 123 = 204 converging occupants

– 204 converging occupants x 0.3”/occ = 61.2” for exit discharge doors


OL Determination : Option 1

1. Print-to-PDF floor plans

2. Determine Function of Use areas

3. Input areas into Occupant Load spreadsheet

4. Input Egress Width multiplier(s)4. Input Egress Width multiplier(s)

5. Determine Occupant Load (OL) by level

6. Create an OL diagram indicating OL on each level

7. Verify stairways and other egress components

widths meet the minimum requirements


BIM/CAD Application : Option 21. Create Area Plans in Revit

2. Set Up Parameters

3. Create a Key Schedule

4. Create an Occupancy Schedule

5. Tag the OL Area Plan

Con :

1

Con :

• Need to manually enter area “values” in

schedule to get them to tag on the plan

since shared and calculated value

parameters cannot be used in a tag


3

4 5

F L A D C O D E F O R U M

T H A N K Y O U F O R

AT T E N D I N G


Determining Occupant Load & Egress Capacity

Engineering

Transcript of Determining Occupant Load & Egress Capacity