Steps in initial investigation of a building site and program


A. Preliminary data

1. Surveys

Plat of Survey (site boundary and existing structure locations)
Utility Survey
Topographic surveys

Click here for example of Plat of Survey

2. Soil testing

Click here for example of soils report

3. Environmental studies made of site

a. PCB hazards
b. Asbestos hazards
c. Lead hazards


B. Gather applicable regulations

1. Contact the city building authority in area of jurisdiction where building will be built
2. Make contact with responsible persons and meet to introduce the project
3. Find out what codes and other laws apply


C. Determine storm water retention requirements
This is usually done by your civil engineer based on hydraulic calculations, but it is important to determine how much of the site is taken up by a retention pond.


D. Investigate possible flood plane requirements
This is usually done by your civil engineer, but you can ask the town in which you are building to show you their flood plane map.

E. Analyze zoning ordinance

a. Building use (occupancy) allowed on site
b. Maximum building area
c. Maximum height
d. Maximum building bulk Floor Area Ratio (FAR) building gross area divided by area of site (this is used in Chicago, but not usually in the suburbs)
e. Set back requirements
f. Parking requirements
g. Accessible Parking Requirements
h. Loading dock requirements
i. Signs


F. Analyze building code

1. Determine occupancy group classifications (building occupancy type)

Click here for a list of occupancy types

2. Determine construction type based on occupancy type, assumed area and assumed height of building.

Type I: Fire resistive: concrete or fireproofed steel

Type II: Non-combustible: concrete or steel, fireproofed or not, depending on level of protection required

Type III: Combustible: concrete, masonry, steel or wood, fireproofed or not depending on level of protection required (normally "ordinary" construction, wood joists and rafters with masonry bearing walls)

Type IV: Heavy timber, minimum sizes of beams and decks, no concealed members

Type V: Combustible: concrete, masonry, steel or wood, fireproofed or not depending on level of protection required (normally wood construction)

3. Determine height and area limitations based on construction type selected

Click here for allowable height and area by construction type

4. List fire resistance ratings for all elements

Click here for fire resistance ratings for each structural element based on construction type

5. Calculate building population for the entire building as well as for each room based on occupancy group (IBC 2003 Section 1004 "Occupant Load," page 195)

6. Determine exit requirements based on required width of each type of exit element calculated using the number of occupants each element will serve

Minimum number of exits for each area of the building as well as the building itself

Maximum travel distance to exits

c. Building compartmentalization requirements, for horizontal exits, high rises, or fire separation demising walls

d. Minimum corridor width

e. Maximum dead end corridor length

7. Stairs

a. Exit stairs must exit directly to outside - there are exceptions
b. Stair locations
c. Stair widths based on population served by each stair
d. Size: Stairs should be min. 44" wide by model codes. (Note that ADA requires a 48" wide stair where there is an area of refuge ("area of rescue assistance")
e. Stair landing width
f. Maximum door encroachment onto stair landings
g. Stair tread and riser requirements and proportions
h. Stair construction type

i. Structural requirements for stairs
j. Stair railings

1. Structural loading requirements for handrails and guards
2. Handrail return to walls
3. Handrail extension requirements
4. Handrail height
5. Handrail encroachment into stair width allowance

8. Ramps

a. Maximum slope and run
b. Minimum ramp width
c. Ramp railings
d. Ramp landings

9. Doors.

a. Door swing direction
b. Minimum door width
c. Door fire ratings
d. Special hardware requirements (panic hardware, knurled handles, closers).

10. Fire resistive requirements.

a. Occupancy separation in multiple occupancy buildings
b. Maximum area.
c. Is a "Fire wall" necessary?
d. Fire separation ratings: corridor walls, stair enclosures
e. Door fire ratings
e. Flame spread requirements for wall, floor and ceiling materials

11. "Fire protection" requirements (sprinkler system)

a. Sprinkler requirements, spacing of heads, water supply.
b. Standpipe requirements, spacing, design, water supply.
c. Fire extinguishers.
d. Fire alarm system.
e. Smoke detection system.
f. Heat detection system.
g. Smoke purge or evacuation ventilation system.

12. Light and ventilation requirements

a. Natural light and ventilation
b. Mechanical ventilation requirements

13. Structure

a. Minimum live load requirements by occupancy
b. Snow loads for roofs
c. Wind loading
dv. Seismic loading

14. Safety glazing requirements for human impact loading.

15. Emergency power supply requirements

a. Exit sign lighting
b. Emergency lighting system

16. Plumbing fixture requirements (from plumbing code)

a. Number of WCs, urinals, and lavatories required
b. Accessible toilet stall requirements
c. Drinking fountain requirements


G. OSHA (Occupational Safety and Health Administration) requirements.

1. Stairs (Width, slope, railings, landings, toe plates)
2. Ramps (width, slopes, railings)
3. Balconies and openings in floors (railings)
4. Ladders


H. Accessibility

1. Three codes need to be analyzed for accessibility requirements:

International Building Code
Americans with Disabilities Act Guidelines (1991)
Illinois Accessibility Code

2. 30" x 48" area of refuge ("rescue assistance") (spaces for wheelchairs) Provide one space for every 200 people on a floor. Increase stair width serving these areas to 48." Note that if building is provided with a supervised fire sprinkler system, you do not have to provide these areas.

3. Where there is a change in level, provide a ramp with maximum 1:12 slope. Provide landings every 30 linear feet of ramp length. Provide railings on both sides of every ramp with handrail extensions at top and bottom.

4 . All landings on ramps are 60" long. Where ramp makes a 90 degree turn, make sure landings are 60" square.

5. Provide min. 18" wall space on latch side of doors.

6. Minimum door width: 36" (32" clear plus stops and door thickness)

7. Provide one 5' x 5' toilet stall along with a 5' diameter turning area in each toilet room.

8. Accessible parking stalls should be shown 12 feet wide. By ADA requirements 1 in 8 stalls have to be 16 feet wide for van parking (Illinois requires that all accessible parking spaces be 16 foot wide).