International Building Code Essentials for Wood Construction Paul D. Coats, PE, CBO Southeast Regional Manager, American Wood Council 1 “The Wood Products Council” is a This course is registered with Registered Provider with The AIA CES for continuing American Institute of Architects professional education. As such, Continuing Education Systems it does not include content that (AIA/CES), Provider #G516. may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or Credit(s) earned on completion of manner ofhandling, using, this course will be reported to AIA distributing, or dealing in any CES for AIA members. Certificates material or product. of Completion for both AIA __________________________________ members and non-AIA members Questions related to specific materials, are available upon request. methods, and services will be addressed at the conclusion of this presentation. Copyright Materials This presentation is protected by US and International Copyright laws. Reproduction, distribution, display and use of the presentation without written permission of AWC is prohibited. © American Wood Council 2016 3 Course Description • Based on the American Wood Council (AWC)/International Code Council publication, Code Conforming Wood Design (CCWD), this presentation provides insight into the 2012 International Building Code (IBC) parameters for wood in non-residential and multi-residential construction. Topics will include maximum building sizes (participants will receive pre-calculated tables for eight occupancies, with and without frontage and sprinkler increases); alternatives for establishing required fire resistance; special provisions for pedestal buildings; precautionary recommendations during construction; criteria for finishes, and other wood features; and the use of AWC design standards and other publications in relation to the IBC. Participants may download a complimentary copy of the CCWD at: http://www.awc.org/codes/ccwdindex.html. 4 Objectives Upon completion, participants will be better able to: 1. Identify building size and use parameters for wood as the primary structural elements. 2. Identify methods specified by the code for establishing fire resistance of wood assemblies and elements, and fire precautions during construction. 3. Apply special provisions for design of wood structures that involve compartmentalization and sprinkler systems. 4. Apply code provisions for the non-structural use of wood in buildings, such as for finishes, appendages, siding, and trim. 5 CCWD Document • This program is based on the Code Conforming Wood Design (CCWD) document • The CCWD is intended as a brief yet comprehensive resource for wood design in accordance with the IBC • Download at (go to “Codes and Standards” and then “Codes”; or just type “CCWD” in the search box) 6 Outline • Building Size • Fire Resistance • Wood Features in Buildings • Precautions During Construction • Highlights 2015 IBC 7 International Building Code • The IBC • Controls building size • Regulates types of materials • Stipulates fire-resistance 8 International Building Code • Concept Fire and Smoke Protection include: • Structural fire-resistance • Limitation of Fire Spread • Protection of Exitways • Radiant Heat Exposure • Restriction of Smoke Movement 9 p. 2-5 of the CCWD OCCUPANCY 10 Classifications p. 2 • Group A, Assembly occupancies • Group B, Business occupancies • Group E, Educational occupancies • Group F, Factory/Industrial occupancies • Group I, Institutional occupancies • Group M, Mercantile occupancies • Group R, Residential occupancies • Group S, Storage occupancies 11 p. 5-6 of the CCWD TYPE OF CONSTRUCTION Types of Construction p. 5 . IBC Chapter 6 • Defines types of construction • Type I & II Non-combustible • Type III Non-combustible & Combustible • Type IV & V Combustible • Wood frame construction is typical in Types III, IV, and V 13 p. 7-12 of the CCWD BUILDING SIZE 14 Allowable Heights and Areas . IBC Chapter 5 contains the general criteria for wood building size • Size thresholds for wood structures are often determined by structural considerations rather than code limitations 15 Table 503 Excerpt, Allowable Building Heights and Areas p. 8 Type of Construction Height Type III Type IV Type V (ft) Group A B HT A B 65 55 65 50 40 Stories (S) Area (A) S 3 2 3 2 1 A-3 A 14,000 9,500 15,000 11,500 6,000 S 5 3 5 3 2 B A 28,500 19,000 36,000 18,000 9,000 S 3 2 3 1 1 E A 23,500 14,500 25,500 18,500 9,500 S 4 2 43 3 1 M A 18,500 12,500 20,500 14,000 9,000 S 4 4 4 3 2 R-1 A 24,000 16,000 20,500 12,000 7,000 S 4 4 4 3 2 R-2 A 24,000 16,000 20,000 12,000 7,000 S 3 2 4 3 1 S-1 A 26,000 17,500 25,500 14,000 9,000 Table 503 Allowable Building Heights and Areas Maximum Allowable Area p. 9 Section 506 Allowable building area per story Aa = {At + [At x If] + [At x Is]} (EQ. 5-1, base equation) Frontage Sprinkler EQ 5-2, factor open frontage If = (F / P – 0.25) x W / 30 (EQ 5-3, weighted average for the width of the open space) W = (L1 × w1 + L2 × w2 + L3 × w3…) / F (w = 20’ min. & 30’ max unless public way) NEW EQ. 18 Maximum Allowable Area Interior Lot Lines L1 = 120 ft, W1 = 15 ft 2012 IBC Clarification L2 = 180 ft L4 = 180 ft, W2 = 25 ft W4 = 30 ft + 22 ft = 52 ft L3 = 120 ft, See p. W3 = 10 ft + 22 ft = 32 ft 11 of CCWD Lot Lines CL Public Way 22ft Street Width 19 W vs. Fire Separation Distance W Bldg. 1 line lot imaginary Bldg. 2 FSD W vs. Fire Separation Distance lot line lot W Bldg. 1 Bldg. 2 FSD FSD centerline of public way W Sprinkler system increases . When a building is equipped throughout with an NFPA 13- compliant automatic sprinkler system (Section 903.3.1.1), the allowable floor area is permitted to be increased: . Is •Single-story building – 3x •Multistory building – 2x 22 Allowable Building Area Calculation •Given: Single-story Type VB grade school •Provided with an NFPA 13-compliant automatic sprinkler system throughout and located on lot as shown. Determine: Maximum allowable 100′ building area 250′ 60′ (see pg. 12 of CCWD) 40′ Maximum Allowable Area Aa = {At + [At x If] + [At x Is]} (Equation 5-1) Aa = {9500 + [9500 x If] + [9500 x Is]} (Table 503) If = (F / P – 0.25) x W / 30 (Equation 5-2) If = (350/700 – 0.25) x 30/30 = .25 (where W > 30, use 30) 100′ 60′ 250′ 40′ Maximum Allowable Area Aa = {At + [At x If] + [At x Is]} (Equation 5-1) Aa = {9500 + [9500 x If] + [9500 x Is]} (Table 503) If = (F / P – 0.25) x W / 30 (Equation 5-2) If = (350/700 – 0.25) x 30/30 = .25 (where W > 30, use 30) Is = 3 for single story (Section 506.3) Aa = {9500 + [9500 x .25] + [9500 x 3]} Aa = 40,375 100′ 60′ Actual area = (250)(100) = 25,000 250′ OK 40′ CCWD • About height limits . 26 Table 503 Excerpt, Allowable Building Heights and Areas Type of Construction Height Type III Type IV Type V (ft) Group A B HT A B 65 55 65 50 40 Stories (S) Area (A) S 3 2 3 2 1 A-1 A 14,000 8,500 15,000 11,500 5,500 S 3 2 3 2 1 A-2 A 14,000 9,500 15,000 11,500 6,000 S 3 2 3 2 1 A-3 A 14,000 9,500 15,000 11,500 6,000 S 3 2 3 2 1 A-4 A 14,000 9,500 15,000 11,500 6,000 S UL UL UL UL UL A-5 A UL UL UL UL UL S 5 3 5 3 2 B A 28,500 19,000 36,000 18,000 9,000 S 3 2 3 1 1 E A 23,500 14,500 25,500 18,500 9,500 Table 503 Excerpt, Allowable Building Heights and Areas Type of Construction Height Type III Type IV Type V (ft) Group A B HT A B 65 55 65 50 40 Stories (S) Area (A) S 3 2 3 2 1 A-1 A 14,000 8,500 15,000 11,500 5,500 S 3 2 3 2 1 A-2 A 14,000 9,500 15,000 11,500 6,000 S 3 2 3 2 1 A-3 A 14,000 9,500 15,000 11,500 6,000 S 3 2 3 2 1 A-4 A 14,000 9,500 15,000 11,500 6,000 S UL UL UL UL UL A-5 A UL UL UL UL UL S 5 3 5 3 2 B A 28,500 19,000 36,000 18,000 9,000 S 3 2 3 1 1 E A 23,500 14,500 25,500 18,500 9,500 Exception . In addition to the area increase, Section 504.2 also permits the Table 503 building heights to be increased: • 20 feet • 1 story above grade. NFPA 13 29 Height Increases for Sprinklers Table 503 limit Height Increases for Sprinklers + 1 story and 20 ft. Table 503 limit CCWD • About Chapter 9 sprinkler thresholds . 32 Chapter 9 Area Limits for Nonsprinklered Buildings • Many occupancies have floor area limits allowed by Chapter 5 that are greater than those permitted in Chapter 9 for nonsprinklered buildings • The same thresholds apply to all construction types, not just wood. The allowable area per story can exceed allowable fire areas and a sprinkler system may be required Chapter 9 Area Limits for Nonsprinklered Buildings Sprinkler Trade-offs • Reductions in corridor ratings and corridor opening protection • Flexibility in means of egress (travel distance to exits, number and separation of exits, common path of travel) • Reductions in dwelling unit separations • Alternate to emergency escape openings • Alternate to certain fire and smoke damper requirements • Interior finish flexibility • Other trade-offs CCWD • About total building area limits.