Code Reference(s):

NBC20, Div. B 3.2.2.

Subject:

EMTC, Various Heights and Occupancy Types, Sprinklered

Title:

New Construction Article Summarizing All EMTC Building Types

Description:

This proposal is for the addition of a new construction Article in 3.2.2. covering a set of entirely new building types of EMTC, all in one consolidated place (i.e., Article/Table 3.2.2.93.), for the sake of simplicity and minimizing downstream effects (i.e., re-numbering) elsewhere in the Code. All new allowances match those suggested by the Transferability Report and generally mirror the IBC. Maximum permitted building heights in the Table reflect the 4.2m/floorplate allowance that is more conducive to EMTC assembly thicknesses, whose adoption is currently before the Standing Committees (SC) for acceptance into the current Code. Sprinklers are required for all proposed buildings. Maximum permitted building areas are determined in a similar fashion to those determined for the original two EMTC construction Articles. While using a Table to summarize new building types is not the typical way to add allowances to 3.2.2., this approach is surmised to be the least disruptive and most streamlined way to add nearly 20 new building archetypes. As research and pplication of EMTC continues to rapidly progress, this approach also enables easy advancement of EMTC allowances in the future.

*Note: this proposed change was provided by the Joint Task Group – Harmonized Variations for Mass Timber*

Related Proposed Change(s):

PCF02, PCF03, PCF04, PCF05, PCF06

PROPOSED CHANGE

3.2.2.93.Encapsulated Mass Timber Construction, Various Heights and Occupancies, Sprinklered

1) A building that is classified as Group A, Division 2, Group B, Division 3, Group C, Group D, Group E, or Group F, Division 2 or 3, is permitted to conform to Sentence (2) provided

a) except as permitted by Sentences 3.2.2.7.(1) and 3.2.2.18.(2), the building is sprinklered,

b) it has a building height not exceeding the number of storeys shown in Table 3.2.2.93. for the applicable major occupancy and minimum encapsulation rating,

c) it has a maximum height that conforms to the value shown in Table 3.2.2.93. for the applicable major occupancy and minimum encapsulation rating that is measured between the floor of the first storey and the uppermost floor level that does not serve a rooftop enclosure for elevator machinery, a stairway or a service room used only for service to the building,

d) it has a maximum building area that conforms to the value shown in Table 3.2.2.93. for the applicable major occupancy, and

e) except as provided in Sentences 3.1.6.3.(4) and 3.1.6.7.(1) and Article 3.1.6.4, the encapsulation rating conforms to the value shown in Table 3.2.2.93. for the applicable major occupancy and maximum building height.

(See Note A-3.2.2.93.(1) and Table 3.2.2.93. See also Articles 3.2.2.48 and 3.2.2.57)

TABLE 3.2.2.93. EMTC Requirements (1) – Forming part of Sentence 3.2.2.93.(1).

MAJOR OCCUPANCY

MAX. BUILDING HEIGHT, STOREYS

MAX. HEIGHT, m

MAX. BUILDING AREA, m2

MINIMUM ENCAPSULATION RATING, min

 

A-2

 

18

76

 

7200

 

70

12

51

50

6

26

0

 

B-3

 

10

42

 

8000

 

70

6

26

50

4

17

0

C

18

76

6000

70

8

34

0

D

18

76

7200

70

9

38

0

 

E

 

12

51

 

6000

 

70

8

34

50

6

26

0

 

F-2

 

10

42

 

4500

 

70

7

30

50

5

21

0

 

F-3

 

12

51

 

7200

 

70

8

34

50

5

21

0

2) Except as provided in Article 3.2.2.16., the building referred to in Sentence (1) is permitted to be of encapsulated mass timber construction or noncombustible construction, used singly or in combination, and

a) except as provided in Sentence (3), floor assemblies shall be fire separations with a fire-resistance rating not less than 2 hours,

b) mezzanines shall have a fire-resistance rating not less than 1 hour, and

c) loadbearing walls, columns and arches shall have a fire-resistance rating not less than that required for the supported assembly.

3) In a building classified as a Group C major occupancy that contains dwelling units that have more than one storey, subject to the requirements of Sentence 3.3.4.2.(3), the floor assemblies, including floors over basements, that are entirely contained within these dwelling units shall have a fire-resistance rating not less than 1 h, but need not be constructed as fire separations.

4) Exit shafts containing scissor stairs in the building referred to in Sentence (1) shall be constructed of concrete.

5) In buildings referred to in Sentence (1) where the roof assembly of the exit stairways or vertical service spaces used as an elevator hoistway has a building height greater than 55 m measured from grade to the highest point of the roof assembly, the enclosure for the stairway or hoistway shall be of encapsulated mass timber construction or constructed of concrete.

3.1.7.5. Rating of Supporting Construction

1) Except as permitted by Sentence (2) and by Articles 3.2.2.20. to 3.2.2.92.3.2.2.93. for mixed types of construction, all loadbearing walls, columns and arches in the storey immediately below a floor or roof assembly required to have a fire-resistance rating shall have a fire-resistance rating not less than that required for the supported floor or roof assembly.

3.1.11.5. Fire Blocks in Horizontal Concealed Spaces

4) Except for crawl spaces conforming to Sentence 3.1.11.6.(1) and except as provided in Sentence (5), in buildings or parts thereof conforming to Article 3.2.2.48., or 3.2.2.57. or 3.2.2.93., horizontal concealed spaces within a floor assembly or roof assembly of encapsulated mass timber construction shall be separated by construction conforming to Article 3.1.11.7. into compartments that are

a) not more than 600 m2 in area with no dimension more than 60 m, if the exposed construction materials within the space have a flame-spread rating not more than 25, and

b) not more than 300 m2 in area with no dimension more than 20 m, if the exposed construction materials within the space have a flame-spread rating more than 25. (See Note A-3.1.11.5.(3) and (4).)

3.1.15.2. Roof Coverings

5) Where buildings or parts thereof conforming to Article 3.2.2.48., 3.2.2.51., 3.2.2.57., or 3.2.2.60., or 3.2.2.93. include non-contiguous roof assemblies at different elevations, the roof coverings referred to in Sentences (3) and (4) are permitted to be evaluated separately to determine the roof covering classification required.

3.2.1.4. Floor Assembly over Basement

1) Except as permitted by Sentence 3.2.2.47.(3), 3.2.2.48.(3), 3.2.2.49.(3), 3.2.2.50.(3), 3.2.2.51.(3), 3.2.2.52.(3), 3.2.2.53.(3), 3.2.2.54.(3), or 3.2.2.55.(3), or 3.2.2.93.(3), a floor assembly immediately above a basement shall be constructed as a fire separation having a fire-resistance rating conforming to the requirements of Articles 3.2.2.20. to 3.2.2.92. 3.2.2.93. for a floor assembly, but not less than 45 min.

3.2.1.6. Mezzanines

1) The floor assembly of a mezzanine that is required to be considered as a storey in calculating the building height shall be constructed in conformance with the fire separation requirements for floor assemblies stated in Articles 3.2.2.20. to 3.2.2.92.3.2.2.93.

3.2.2.2. Special and Unusual Structures

1) A structure that cannot be identified with the characteristics of a building in Articles 3.2.2.20. to 3.2.2.92.3.2.2.93. shall be protected against fire spread and collapse in conformance with good fire protection engineering practice. (See Note A-3.2.2.2.(1).) (See also Notes A-3 and A-3.2.5.12.(1).)

3.2.2.11. Exterior Balconies

1) Except as provided in Sentence (2), an exterior balcony shall be constructed in accordance with the type of construction required by Articles 3.2.2.20. to 3.2.2.92.3.2.2.93., as applicable to the occupancy classification of the building.

2) The floor assembly of an exterior balcony in a building or part of a building conforming to Article 3.2.2.48., or 3.2.2.57., or 3.2.2.93. shall

a) be of noncombustible construction, or

b) be constructed in accordance with Article 3.1.6.3., but need not comply with Sentence 3.1.6.4.(1).

3.2.2.12. Exterior Passageways

1) An elevated exterior passageway used as part of a means of egress shall conform to the requirements of Articles 3.2.2.20. to 3.2.2.92.3.2.2.93. for mezzanines.

3.2.2.13. Occupancy on Roof

1) A portion of a roof that supports an occupancy shall be constructed in conformance with the fire separation requirements of Articles 3.2.2.20. to 3.2.2.92.3.2.2.93. for floor assemblies, and not the fire-resistance rating for roof assemblies.

3.2.2.14. Rooftop Enclosures

1) A rooftop enclosure for elevator machinery or for a service room shall be constructed in accordance with the type of construction required by Articles 3.2.2.20. to 3.2.2.92.3.2.2.93.

2) A rooftop enclosure for elevator machinery or for a service room, not more than one storey high, is not required to have a fire-resistance rating.

3) A rooftop enclosure for a stairway shall be constructed in accordance with the type of construction required by Articles 3.2.2.20. to 3.2.2.92.3.2.2.93.

3.2.2.16. Heavy Timber Roof Permitted

1) Unless otherwise permitted by Articles 3.2.2.20. to 3.2.2.92.3.2.2.93., a roof assembly in a building up to 2 storeys in building height is permitted to be of heavy timber construction regardless of building area or type of construction required, provided the building is sprinklered throughout.

3.2.2.18. Automatic Sprinkler System

1) Except as permitted by Sentence (2), an automatic sprinkler system conforming to the requirements of Articles 3.2.4.7., 3.2.4.8., 3.2.4.9. and 3.2.5.12. shall be installed throughout a building regulated by one or more of Articles 3.2.2.20., 3.2.2.21., 3.2.2.22., 3.2.2.23., 3.2.2.24., 3.2.2.26., 3.2.2.27., 3.2.2.29., 3.2.2.31., 3.2.2.33., 3.2.2.36., 3.2.2.37., 3.2.2.38., 3.2.2.39., 3.2.2.40., 3.2.2.41., 3.2.2.42., 3.2.2.43., 3.2.2.44., 3.2.2.45., 3.2.2.46., 3.2.2.47., 3.2.2.48., 3.2.2.49., 3.2.2.51., 3.2.2.52., 3.2.2.55., 3.2.2.56., 3.2.2.57., 3.2.2.59., 3.2.2.60., 3.2.2.61., 3.2.2.63., 3.2.2.65., 3.2.2.66., 3.2.2.67., 3.2.2.69., 3.2.2.71., 3.2.2.72., 3.2.2.73., 3.2.2.74., 3.2.2.76., 3.2.2.77., 3.2.2.79., 3.2.2.81., 3.2.2.82., 3.2.2.84., 3.2.2.86., 3.2.2.88., and 3.2.2.90. and 3.2.2.93.

2) If a storey in a building or a floor area is required to have an automatic sprinkler system installed throughout in accordance with one or more of Articles 3.2.2.20. to 3.2.2.92 3.2.2.93. or Section 3.3., the automatic sprinkler system shall also be installed throughout all lower storeys in the building notwithstanding permission in Articles 3.2.2.20. to 3.2.2.92 3.2.2.93. to construct one or more of those storeys without installing automatic sprinkler protection. (See Note A-3.2.2.18.(2).)

3.2.2.19. Buildings Containing Impeded Egress Zones

1) A building containing an impeded egress zone and conforming to the appropriate requirements of Articles 3.2.2.20. to 3.2.2.92.3.2.2.93. is not required to conform to the requirements of Articles 3.2.2.36. and 3.2.2.37. for a Group B, Division 1 major occupancy provided

a) the building is sprinklered throughout,

b) it is not more than 1 storey in building height,

c) it does not include

ii) a contained use area,

ii) sleeping accommodation,

iii) a high-hazard industrial occupancy, or

iv) a mercantile occupancy,

d) the building area is not more than 6 400 m2 if the building includes a medium-hazard industrial occupancy,

e) the impeded egress zone does not extend beyond the boundaries of the fire compartment in which it is located, and

f) the occupant load of the impeded egress zone is not more than 100.

3.2.2.23. Group A, Division 2, Any Height, Any Area, Sprinklered

1) Except as permitted by Articles 3.2.2.24. to 3.2.2.28. and 3.2.2.93., a building classified as Group A, Division 2 shall conform to Sentence (2).

3.2.2.42. Group B, Division 3, Any Height, Any Area, Sprinklered

1) Except as permitted by Articles 3.2.2.43. to 3.2.2.46. and 3.2.2.93., a building classified as Group B, Division 3 shall conform to Sentence (2).

3.2.2.47. Group C, Any Height, Any Area, Sprinklered

1) Except as permitted by Articles 3.2.2.48. to 3.2.2.55. and 3.2.2.93., a building classified as Group C shall conform to Sentence (2).

3.2.2.56. Group D, Any Height, Any Area, Sprinklered

1) Except as permitted by Articles 3.2.2.57. to 3.2.2.65. and 3.2.2.93., a building classified as Group D shall conform to Sentence (2).

3.2.2.66. Group E, Any Height, Any Area, Sprinklered

1) Except as permitted by Articles 3.2.2.67. to 3.2.2.71. and 3.2.2.93., a building classified as Group E shall conform to Sentence (2).

3.2.2.76. Group F, Division 2, Any Height, Any Area, Sprinklered

1) Except as permitted by Articles 3.2.2.77. to 3.2.2.81. and 3.2.2.93., a building classified as Group F, Division 2 shall conform to Sentence (2).

3.2.2.82. Group F, Division 3, Any Height, Any Area, Sprinklered

1) Except as permitted by Articles 3.2.2.83. to 3.2.2.92.3.2.2.93., a building classified as Group F, Division 3 shall conform to Sentence (2).

3.2.3.9. Protection of Structural Members

1) Structural members, including beams, columns and arches, that are placed wholly or partly outside the exterior face of a building and are less than 3 m from the property line or the centre line of a public thoroughfare shall be protected from exterior fire exposure by fire protection having a fire-resistance rating not less than that required for their protection from interior fire exposure, as stated in Articles 3.2.2.20. to 3.2.2.92.3.2.2.93., but not less than 1 h.

3.2.5.12. Automatic Sprinkler Systems

7) Notwithstanding the requirements of the standards referenced in Sentences (1) and (2) regarding the installation of automatic sprinkler systems, in buildings conforming to Article 3.2.2.48., 3.2.2.51., 3.2.2.57., or 3.2.2.60. or 3.2.2.93., sprinklers shall be provided for balconies and decks exceeding 610 mm in depth measured perpendicular to the exterior wall. (See Note A-3.2.5.12.(7).)

3.2.6. Additional Requirements for High Buildings

3.2.6.1. Application

2) This Subsection applies to a building or part of a building constructed in conformance with Article 3.2.2.57. or 3.2.2.93. in which the floor level of the highest storey is more than 18 m above grade.

3.3.3.7. Contained Use Areas

4) A contained use area, in a building for which Articles 3.2.2.20. to 3.2.2.92.3.2.2.93. do not require the installation of an automatic sprinkler system, is not required to be sprinklered as required by Sentence (3) provided

a) the building is designed so that during a period of 2 h after the start of a fire in the contained use area other fire compartments will not contain more than 1% by volume of contaminated air from the contained use area,

b) the building is designed so that during a period of 2 h after the start of a fire in another part of the building the contained use area will not contain more than 1% by volume of contaminated air from the other part of the building,

c) all doors are designed to be remotely released in conformance with Sentence 3.3.1.13.(6), and

d) the contained use area does not contain any rooms lined with combustible padding.

Note A-3.1.11.5.(3) and (4) Fire Blocks in Concealed Spaces. To reduce the risk of fire spread in combustible concealed spaces within the types of buildings referred to in Sentences 3.1.11.5.(3) and (4), fire blocking is required regardless of whether the horizontal concealed space is protected by sprinklers or not, unless the space is filled with noncombustible insulation so that any air gap at the top of the insulation is very small. (See also Note A-3.1.11.5.(1) for roof venting.)

A 5- or 6-storey building constructed in accordance with Article 3.2.2.51. and buildings constructed in accordance with Article 3.2.2.48., 3.2.2.57., or 3.2.2.60. or 3.2.2.93. are required to be sprinklered in accordance with NFPA 13, “Standard for the Installation of Sprinkler Systems” (see Article 3.2.5.12.). NFPA 13 generally requires sprinklering of any concealed spaces of combustible construction or where large amounts of combustibles are present. However, NFPA 13 allows combustible concealed spaces not to be sprinklered in certain cases, including where concealed spaces are filled almost entirely with noncombustible insulation, where spaces contain only materials with a low flame-spread rating, and where limited access or the size of the space makes it impractical to install sprinklers. For certain types of construction in combustible concealed spaces that are not sprinklered, NFPA 13 mandates fire blocking beyond the minimum specified in Sentence 3.1.11.5.(3).

Note A-3.2.2.93.(1) and Table 3.2.2.93. Occupancy Combinations in Buildings of Mixed Encapsulation Ratings. Buildings conforming to the building height and minimum encapsulation rating requirements and the other fire protection requirements of Article 3.2.2.93. may be entirely constructed of encapsulated mass timber construction and incorporate the multiple major occupancies otherwise permitted by Articles 3.2.2.4. to 3.2.2.6. This would also include permitting mixing of major occupancies that require different levels of encapsulation for structural mass timber elements in accordance with Table 3.2.2.93.

Objective-Based Analysis of New Provision

3.2.2.93. Encapsulated Mass Timber Construction, Various Heights and Occupancies, Sprinklered

(2)

(b), (c) [F04 – OS1.3]

(b), (c) [F04 – OP1.3]

(a), (c) [F03 – OS1.2][F04 – OS1.2, OS1.3]

(a), (c) [F03 – OP1.2][F04 – OP1.2, OP1.3]