The Ontario Building Code | Importance Factor
4.1.8.5. Importance Factor
(1) The earthquake importance factor, IE, shall be determined according to Table 4.1.8.5.
Table 4.1.8.5.
Importance Factor for Earthquake Loads and Effects, IE
Forming Part of Sentence 4.1.8.5.(1)
| Item | Column 1 | Column 2 | Column 3 |
|
| Importance Category | Importance Factor, IE |
|
|
|
| ULS | SLS(1) |
| 1. | Low | 0.8 |
|
| 2. | Normal | 1.0 |
|
| 3. | High | 1.3 |
|
| 4. | Post-disaster | 1.5 |
|
Notes to Table 4.1.8.5.:
(1) See Article 4.1.8.13.
In Plain Language
The earthquake importance factor, which scales up seismic design requirements for buildings where failure would have more serious consequences (like hospitals or emergency response facilities), is determined from a dedicated importance-factor table.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.