International Building Code Chapters 3, 5, 6 and 10

2012 INTERNATIONAL BUILDING CODE (IBC)

Chapters 2, 3, 5, 6 and 10

CENG 3434: Civil Engineering Materials, Codes and Specifications

DO NOT MISPLACE

CHAPTER 6

TYPES OF CONSTRUCTION

SECTION 601 GENERAL

S Scope. The provisions of this chapter shall control the ification of buildings as to type of construction.

SECTION 602 CONSTRUCTION CLASSIFICATION

.1 General. Buildings and structures erected or to be fled, altered or extended in height or area shall be classi- in one of the five construction types defined in Sections

.. 2 through 602.5. The building elements shall have afire- tance rating not less than that specified in Table 601 and

erior walls shall have afi re- resistance rating not less than specified in Table 602. Where required to have a fire-

. lance rating by Table 601, building elements shall com- ith the applicable provisions of Section 703.2. The pro-

'on of openings, ducts and air transfer openings in !ding elements shall not be required unless required by er provisions of this code .

~ 2.1.l Minimum requirements. A building or portion reof shall not be required to co nform to the detail s of .a e of construction higher than that ty pe which meets the

minimum requirements based on occupancy even though

certain features of such a buildin g actually conform to a hi gher type of construction.

602.2 Types I and II. Types I and II construction are those types of construction in which the building elements listed in Table 601 are of noncombustible materials, except as permit- ted in Section 603 and elsewhere in this code.

602.3 Type III. Type III construction is th at type of construc- tion in which the exterior wall s are of noncombustible materi- als and the interior building elements are of any material permitted by this code. Fire-retardant-treated wood framing complying with Section 2303.2 shall be permitted within exte rior wall assemblies of a 2-hour rating or less.

602.4 Type IV. Type IV construction (Heavy Timber, HT) is that type of construction in which the exterior walls are of noncombu stible materi als and the interior building elements are of solid or laminated wood wi thout concealed spaces. The details of Type IV construction shall comply with the provi- sions of thi s section . Fire- retarda nt-treated wood framing complying with Section 2303.2 shall be permitted wi thin exterior wall assemblies wi th a 2-hour rating or less. Mini- mum solid sawn nominal dimen sion s are required for struc- tures built using Type IV construction (HT). For glued- laminated members the equivalent net finished width and depths corresponding to the minimum nominal width and

TABLE 601 FIRE-RESISTANCE RATING REQUIREMENTS FOR BUILDING ELEMENTS {HOURS)

TYPEI TYPE II TYPE Ill TYPE IV TYPE V BUILDING ELEMENT

A B Ad B Ad B HT Ad B

:nary structural fra m eg (see Section 2 02) 3' 2' 1 0 I 0 HT 1 0 g walls

xterior·g 3 2 1 0 2 2 2 1 0 1terior 3' 2" 1 0 1 0 l/HT 1 0

nbearing walls and partitions S ee Table 602

~terior

nbeari ng walls a nd partition s See

0 0 0 0 0 0 Section 0 0 1terior

602.4.6

or constructio n and associated secondary members 2 2 1 0 1 0 HT 1 0

see Section 202)

of construction a nd a ssociated secondary members I 'lib J b,c 1 b,c o c 1 b.c 0 HT J b,c 0

~ee Section 202)

' SI: I foot= 304.8 mm. loofs upports: Fire-resista nc e ratin gs of primary structural fra me and bearing wall s are permitted to be reduced by I hour where supporti ng a roo f onl y. lxcept in Group F-1 , H , M and S-1 occ up ancies, fire protection of structural members shall not be required, including protection of roof framing and decking here every part of the roof co nstruction is 20 feet or more above any floor immed iately below . Fire-retardant-treated wood members shall be allowed to be

5ed for such unprotected members. Dall occupancies, heavy timber shall be all owed where a I-h our or less fire- resistance rating is required.

approved automati c sprin kler sys tem in accordance with Section 903.3. 1.1 shall be allo wed to be sub stituted for 1-ho ur fire -resis tance-rated co nst ruction , rovided such syste m is not otherwise req uired by other provisions of th e code o r used for an all owable area increase in acco rd ance with Sec ti on 506 .3 or an !lowable height increase in accordance with Secti on 504. 2. The I-h our substitution for the fire res istance of ex terior wal ls shall no t be pe rmitted. lot less than the fire -res istance rat ing req uired by other section s of thi s code. lot less than the fire -res istan ce rating based on fire separatio n di stance (see Table 602). lot less than th e fire -resistance rat in g as referenced in Section 704. l 0

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TYPES OF CONSTRUCTION

G depths of solid sawn lumber are required as specified in Table 602.4 .

TABLE 602.4 WOOD MEMBER SIZE EQUIVALENCIES

MINIMUM NOMINAL SOLID MINIMUM GLUED-LAMINATED SAWN SIZE NET SIZE

Width, inch Depth , inch Width, inch Depth, inch

8 8 63/4 3114

6 10 5 10 1/2

6 8 5 3114

6 6 5 6

4 6 3 67/8

Fo r SI: 1 inch= 25.4 mm.

602.4.1 Columns. Wood column s shall be sawn or glued laminated and shall be not less than 8 inches (203 mm), nominal , in any dimension where suppo1ting floor loads and not less th an 6 inches (152 mm) nominal in wi dth and not less than 8 inches (203 mm) nomin al in depth where supporting roof and ceiling loads only. Columns shall be continuous or superimposed and connected in an approved manner.

602.4.2 Floor framing. Wood beams and girders shall be of sawn or glued-lamin ated timber and shall be not less than 6 inches ( I 52 mm) nominal in width and not less than 10 inches (254 mm) nomin al in depth . Framed sawn or glu ed-l amin ated timber arches, which spring from the floor line and support floor loads, shall be not less than 8 inches (203 mm) nominal in any dimension. Framed tim- ber trusses supporting floor loads shall have members of not less than 8 inches (203 mm) nominal in any dimen- sion.

602.4.3 Roof framing. Wood-frame or glued-l aminated arches for roof construction, which spring from the floo r line or from grade and do not support floor loads, shall have members not less than 6 inches (152 mm) nominal in

TABLE 602

width and have not less than 8 inches (203 mm) nomin in depth for the lower half of the height and not less than inches (152 mm) nominal in depth for the upper hal Framed or glued-laminated arches for roof construction that spring from the top of walls or wall abutments, frame timber trusses and other roof framing, which do not sup port floor loads, shall have members not less than 4 inche (1 02 mm) nominal in width and not les s than 6 inches (15 mm) nominal in depth . Spaced members shall be permit ted to be composed of two or more pieces not le'ss than inches (76 mm) nominal in thickness where blocked sol· idly throughout their intervening spaces or where space are tightly closed by a continuous wood cover plate of no less than 2 inches (5 1 mm) nominal in thickness secured the underside of the members. Splice plates shal l be n less than 3 inches (76 mm) nomin al in thickness. Wher protected by approved automatic sprinklers under the roof deck, framing members shall be not less than 3 inches (7 mm) nominal in width.

602.4.4 Floors. Floors shall be without concealed spac Wood floors shall be of sawn or glued-laminated pla splined or tongue-and-groove , of not less than 3 inches (7 mm) nominal in thickness covered with 1-inch (25 mm nominal dimension tongue-and-groove flooring , la· crosswise or diagonally, or 0.5-inch (12.7 mm) particle board or planks not less than 4 inches (102 mm) nomin in width set on edge close together and well spiked a covered with 1-inch (25 mm) nominal dimension flooring or 15/ 32-inch (12 mm) wood structural panel or 0.5 -inch- (12.7 mm) particleboard. The lumber shall be laid so th at no continuous line of joints will occur except at points of support. Floors shall not extend closer than 0.5 inch (12.7 . mm) to walls. Such 0.5 -inch (12.7 mm) space shall be cov- ·~ ered by a molding fastened to the wall and so arranged that · it will not obstruct the swelling or shrinkage movements: of the floor. Corbeling of masonry walls under the floor - shall be permitted to be used in place of molding.

FIRE-RESISTANCE RATING REQUIREMENTS FOR EXTERIOR WALLS BASED ON FIRE SEPARATION DISTANCE"· e, h

FIRE SEPARATION DISTANCE= TYPE OF CONSTRUCTION OCCUPANCY GROUP H'

OCCUPANCY OCCUPANCY X(feet) GROUP F-1, M, S-1 9 GROUP A, B, E, F-2, I, R, S-29 , U'

X<S' All 3 2

S:o;X<lO IA 3 2

Others 2

IA, IB 2 I l d 10 :o; x < 30 IIB , VB 0 0

Others 1 1 ld

X2':30 All 0 0 0

For SI: 1 foot = 304.8 mm .

a. Load-be aring exterior walls shall also comply with the fire-re sist.a nce rat in g requirements of Table 601.

b. For spec ial requirements for Group U occ upanc ies, see Section 406.3. c. See Section 706.1.1 for parry walls. d. Open parking garages co m ply in g with Section 406 shall not be required to have a fire-resistance rating.

\ J e. The fire-res ista nce ra ting of an ex te rior wall is determined based upon the fire separation di sta nce of the exteri or wall and th e story in w hi ch the wall is < .......__..,. located. .

f. For spec ial requ irements fo r Gro up H occ upanc ies, see Section 4 15 .5. g. For spec ial requ ire me nts for Group S aircraft hangars, see Section 412.4. 1.

I h . Where Tab le 705.8 perm it s non bea rin g ex terior wall s wi th unlimi ted area of un protected ope nin gs, th e required fire-resistance ratin g fo r th e exterior wall s is 0 ho urs. 108 2012 INTERNATIONAL BUILDING CODE®.

602.4.5 Roofs. Roofs shall be without concealed spaces and wood roof decks shall be sawn or glued laminated, splined or tongue-and-groove plank, not less than 2 inches (51 mm) nominal in thickness , 11/ 8-inch-thick (32 mm) wood structural panel (exterior glue), or of planks not less than 3 inches (76 mm) nominal in width, set on edge close together and laid as required for floors. Other types of decking shall be permitted to be used if providing equiva- lent.fire resistance and structural properties .

602.4.6 Partitions. Partitions shall be of solid wood con- struction formed by not less than two layers of 1-inch (25 mm) matched boards or laminated construction 4 inches (102 mm) thick, or of 1-hour fire-resistance-rated con-

602.4.7 Exterior structural members. Where a horizon- tal separation of 20 feet (6096 mm) or more is provided, wood columns and arches conforming to heavy timber sizes shall be permitted to be used externally.

02.5 Type V. Type V construction is that type of construc- ·on in which the structural elements, exterior walls and inte-

rior walls are of any materials permitted by this code.

SECTION 603 COMBUSTIBLE MATERIAL IN TYPE I AND II

CONSTRUCTION

3.LAIJowable materials. Combustible materials shall be "tted in buildings of Type I or II construction in the fol-

wing applications and in accordance with Sections 603 .1.1 ough 603 .1.3 :

1. Fire-retardant-treated wood shall be permitted in:

1.1. Nonbearing partitions where the required fire- resistance rating is 2 hours or less.

1.2. Nonbearing exterior walls where fire-resistance rated construction is not required.

1.3. Roof construction, including girders, trusses, framing and decking .

Exception: In buildings of Type IA construction exceeding two stories above grade plane, fire-retar- dant-treated wood is not permitted in roof construction where the vertical distance from the upper floor to the

• roof is less than 20 feet (6096 mm).

2. Thermal and acoustical insulation, other than foam plastics, having aflame spread index of not more than 25.

l. Insulation placed between two layers of non- combustible materials without an intervening airspace shall be allowed to have a flame spread index of not more than 100.

2. Insulation installed between a finished floor and solid decking without intervening airspace shall be allowed to have a flame spread index of not more than 200.

3. Foam plastics in accordance with Chapter 26 .

TYPES OF CONSTRUCTION

4. Roof coverings that have an A, B or C classifi- cation.

5. Interior floor finish and floor covering materi- als installed in accordance with Section 804.

6. Millwork such as doors, door frames, window sashes and frames.

7. Interior wall and ceiling finishes installed in accordance with Sections 801 and 803 .

8. Trim installed in accordance with Section 806.

9. Where not installed greater than 15 feet (4572 mm) above grade, show windows, nailing or furring strips and wooden bulkheads below show windows, including their frames, aprons and show cases.

10. Finish flooring installed in accordance with Section 805.

11. Partitions dividing portions of stores, offices or similar places occupied by one tenant only and that do not establish a corridor serving an occu- pant load of 30 or more shall be permitted to be constructed of fire-retardant-treated wood, !- hour fire -resistance-rated construction or of wood panels or similar light construction up to 6 feet (1829 mm) in height.

12. Stages and platforms constructed in accordance with Sections 410.3 and 410.4, respectively.

13. Combustible exterior wall coverings, balconies and similar projections and bay or oriel win- dows in accordance with Chapter 14.

14. Blocking such as for handrails, millwork, cabi- nets and window and door frames .

15. Light-transmitting plastics as permitted by Chapter 26.

16. Mastics and caulking materials applied to pro- vide flexible seals between components of exte- rior wall construction .

17. Exterior plastic veneer installed in accordance with Section 2605.2.

18. Nailing or furring strips as permitted by Section ~03.4 .

19. Heavy timber as permitted by Note c to Table 601 and Sections 602.4.7 and 1406.3.

20. Aggregates, component materials and admix- tures as permitted by Section 703.2.2 .

21. Sprayed fire-resistant materials and intumes- cent and mastic fire -resistant coatings , deter- mined on the basis of fire-resistance tests in accordance with Section 703 .2 and installed in accordance with Sections 1705.13 and 1705.14, respectively.

22. Materials used to protect penetrations in fire- resistance-rated assemblies in accordance with Section 714.

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TYPES OF CONSTRUCTION

23. Materials used to protect JOmts in fire -resis - tance-rated assemblies in accordance with Sec- tion 715.

24. Materials allowed in the concealed spaces of buildings of Types I and II construction m accordance with Section 718.5.

25. Materials exposed within plenums complying with Section 602 of the International Mechani- cal Code.

603.1.1 Ducts. The use of nonmetallic duct~ shall be per- mitted where installed in accordance with the limitations of the International Mechanical Code .

603.1.2 Piping. The use of combustible piping materials shall be permitted where installed in accordance with the limitations of the International Mechanical Code and the International Plumbing Code.

603.1.3 Electrical. The use of electrical wiring methods with combustible insulation, tubing, raceways and related components shall be permitted where installed in accor- dance with the limitations of this code.

110 2012 INTERNATIONAL BUILDING CODE'