The Ontario Building Code | Group F, Division 2, up to 4 Storeys
3.2.2.70. Group F, Division 2, up to 4 Storeys
(1) A building classified as Group F, Division 2 is permitted to conform to Sentence (2) provided,
(a) it is not more than 4 storeys in building height, and
(b) it has a building area not more than the value in Table 3.2.2.70.A. or Table 3.2.2.70.B.
(2) The building referred to in Sentence (1) shall be of combustible construction or noncombustible construction used singly or in combination, and,
(a) floor assemblies shall be fire separations with a fire-resistance rating not less than 45 min,
(b) mezzaninesshall have, if of combustible construction, a fire-resistance rating not less than 45 min,
(c) if the buildingis not sprinklered, roof assemblies shall have, if of combustible construction, a fire-resistance rating not less than 45 min, except that in buildings not more than 1 storeyin building height, the fire-resistance rating is permitted to be waived provided the roof assembly is constructed as a fire-retardant treated wood roof system conforming to Article 3.1.14.1., and the building area is not more than,
(i) 1 600 m2if facing one street,
(ii) 2 000 m2if facing two streets, or
(iii) 2 400 m2if facing three streets,
(d) loadbearingwalls, columns and arches supporting an assembly required to have a fire-resistance rating shall,
(i) have a fire-resistance rating not less than 45 min, or
(ii) be of noncombustible construction, and
(e) loadbearingwalls, columns and arches supporting a fire separationshall have a fire-resistance rating not less than that required for the supported assembly.
Table 3.2.2.70.A.
Maximum Building Area, Group F, Division 2, up to 4 Storeys
Forming Part of Sentence 3.2.2.70.(1)
| Item | Column 1 | Column 2 | Column 3 | Column 4 |
|
| No. of Storeys | Maximum Area, m2 |
|
|
|
|
| Facing 1 Street | Facing 2 Streets | Facing 3 Streets |
| 1. | 1 | 3 200 | 4 000 | 4 800 |
| 2. | 2 | 1 600 | 2 000 | 2 400 |
| 3. | 3 | 1 070 | 1 340 | 1 600 |
| 4. | 4 | 800 | 1 000 | 1 200 |
Table 3.2.2.70.B.
Maximum Building Area, Group F, Division 2, up to 4 Storeys, Increased Area, Sprinklered
Forming Part of Sentence 3.2.2.70.(1)
| Item | Column 1 No. of Storeys | Column 2 Maximum Area, m2 |
| 1. | 1 | 9 600 |
| 2. | 2 | 4 800 |
| 3. | 3 | 3 200 |
| 4. | 4 | 2 400 |
In Plain Language
This article sets one of the specific size-and-construction packages available for a Group F, Division 2 buildings building: up to 4 storeys, area per Tables 3.2.2.70.A/B, combustible or noncombustible construction with 45-minute floor assemblies. Designers can choose whichever of the several packages in this Subsection best fits the building being planned, trading height and area against construction type, sprinklering, and fire-resistance rating requirements.
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.