Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


How to Calculate Building Area Modifications

This prezi will teach you step-by-step how to calculate building area modifications according to the 2009 IBC Sect. 506.1

Joshua Herrera

on 2 July 2014

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of How to Calculate Building Area Modifications

Sprinkler Increase
If a building has sprinklers installed in accordance with Section 903.3.1.1 the following values of I_s are used:
Building areas limited by Table 503 shall be permitted to be increased due to frontage ( ) and sprinkler protection ( ) in accordance with the following:
Equation 5-1, Sect. 506.1
= Allowable building area per story (ft^2)
= Tabular building area per story in accordance with Table
503 (ft^2)
= Area increase factor due to frontage as calculated in
accordance with section 506.2
= Area increase factor due to sprinkler protection as
calculated in accordance with section 506.3
1. Eliminate all perimeters that are within 20 ft. of their front.
2. Add the remaining perimeters
1. Add the perimeter of the entire building.
1. Eliminate all perimeters that are within 20 ft. of their front.
2. Multiply the remaining perimeters by their respective fronts (use 30' for all fronts > 30')
One Story
Building can increase by 300%
More than one story above grade
Building can increase by 200%
Sprinkler increase is not permitted for H-1, H-2, and H-3 occupancies.
See sect. 506.3 for exception details
Let's look at an example to learn how to calculate A_a.
We have determined the requested addition meets the code.
Allowable area (per floor): 30,090'
Tabular story limit: 2
Revised story limit (*Sect. 504.2): 3
Total allowable area: 30090' x 3 = 90270'
2009 IBC - Section 506
Allowable Building Area
Step 1:
Building Area Modifications
Calculate Frontage Increase
Allowable Building Area per Story
Plug the values of our previous equations into the allowable area equation:
Final Checklist
F = Building perimeter that fronts on a public way or open space having 20 feet (6090 mm) open minimum width.
Calculate F
P = Perimeter of the entire building.
Calculate P
W = Width of public way or open space in accordance with section 506.2.1.
Calculate W
3. Add all the values up and divide by F
If the value in brackets is not >0, then I_f=0
Calculate I_f
Calculate I_s
Calculate A_a
Table 503 in the IBC sets an allowable height and area for a building depending on its type of construction and group.
*Disclaimer: This presentation is only intended for educational purposes. All code related decisions need to follow the IBC adopted by your state or organization.
A building owner has a 1 story building shown in fig. 1.
Construction Type: IIB
Group: A-1
Building area: 6900 ft^2
Sprinklered: Yes
Fig. 1
The owner would like to increase his building to a 3 story building with an area of 25,000 ft^2 per floor.
Need to find: F, P, and W
Let's calculate the increase due to frontage and sprinklers to determine if the addition is feasible.
Table 503 limitations on this building:
- 2 stories
- 8500 ft^2 per floor
For our example I_s=3
*Sect. 504.2 allows for max building height increase and a max number of stories increased for some sprinklered buildings. See section for details.
Section 507 allows the increase of certain buildings to be virtually unlimited if they are surrounded and adjoined by public ways or yards not less than 60 feet in width. See section for details.
The value of (W/30) must be < or =1. See section 506.2.1 for exceptions.
Proposed area (per floor): 25,000'
Proposed stories: 3
Full transcript