Please add relevant logo here. Designing Modern Wood Schools: A Guide for Architects and Structural Engineers

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1 Please add relevant logo here Designing Modern Wood Schools: A Guide for Architects and Structural Engineers

2 The Wood Products Council is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES), Provider #G516. Credit(s) earned on completion of this course will be reported to AIA CES for AIA members. Certificates of Completion for both AIA members and non-aia members are available upon request. This course is registered with AIA CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

3 Course Description This course is intended for architects and structural engineers who are seeking a full system understanding of the unique design considerations associated with wood-frame schools. Architectural design and detailing topics specific to school performance criteria such as durability, fire and life safety, and allowable building size will be discussed. Schools space planning needs will be highlighted as will construction type selection and opportunities for wood use. Structural design steps, considerations, and detailing best practices related to gravity and lateral analysis of common school configurations such as classroom floor design and corridor wall framing will also be covered, along with options for wood-frame tall walls and long-span roofs in open areas such as gyms. With an emphasis on budget, this course will present designers with the information necessary to utilize wood framing as a cost savings tool.

4 Learning Objectives 1. Review provisions of the International Building Code specific to school buildings and discuss opportunities for and application of traditional light wood framing and exposed heavy timber framing in school construction. 2. Discuss structural design steps and considerations unique to school buildings, including framing options for common school space planning needs. 3. Explore design and detailing best practices used to achieve performance objectives in school assembly design, such as acoustics, durability and accommodation of MEP. 4. Demonstrate examples of modern wood-frame school facilities, including reasons for choosing wood and the specific framing options.

5 What is a wood framed school? Agenda 1. State of modern school construction 2. Building size & Space planning 3. Assembly design

6 total US school construction costs in 2015 $12.9 billion Source: school planning & management - the state of school construction, 2015 report

7 $6.1 Billion new construction $3.7 Billion Additions $3.1 Billion renovations $12.9 billion Source: school planning & management - the state of school construction, 2015 report

8 396 MM SFnon-residential construction in us, 2015, 1-6 stories 88 MM SFEducational facility construction in us, 2015, 1-6 stories 22% Source: dodge construction data

9 Projections for What s down the road More students = need for more school construction

10 Nationwide projections by 2024: K-12: enrollment increases by 2.9 MM (5.3%) Most is k-8: 2.6 MM (6.8%) Colleges & universities: enrollment increases 2.9 MM (14.2%) Source: national center for education statistics & 2016 dodge construction outlook

11 Nationwide projections enrollment increases expected to greatly exceed those over the past decade. Result = prospects for renewed focus on education infrastructure construction growth 2017 projected educational facility construction: 148 MM sf - 12% increase over 2016 projections 2018 projected educational facility construction: 175 MM sf - 18% increase over 2017 projections Source: 2017 dodge construction outlook

12 Source: 2016 dodge construction outlook

13 Nationwide projections American society of civil engineers gave us school infrastructure grade of d estimate that $270 B of investment is needed to modernize and maintain schools in us Source: 2013 asce infrastructure report card

14 National averages 2015: Elementary: 80,000 sf, $210/sf, 135 sf/student Middle school: 117,000 sf, $270/sf, 180 sf/student High school: 154,700 sf, $267/sf, 182 sf/student Source: school planning & management - the state of school construction, 2015 report

15 Avg. school building size Total area ft 2 wood other # of stories Source: 2015 dodge construction data

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17 Icc building valuation data, e occupancy buildings, august 2016 Cost per SF $192 ia $185 ib $180 iia $172 iib $161 iiia $153 $iiib $$140 $136 $ va vb Construction Type

18 School Base Allowable Sizes IBC Table 503 Allowable building size IBC chapter 5

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20 Type III Exterior walls non-combustible (may be FRTW) Interior elements any allowed by code Construction types IBC 602 Type V All building elements are any allowed by code Types III and V are subdivided to A (protected) and B (unprotected) Type IV (Heavy Timber) Exterior walls non-combustible (may be FRTW) Interior elements qualify as Heavy Timber (min. sizes, no concealed spaces)

21 Allowable building size IBC table 503

22 Allowable building size IBC table 503 How do we go bigger?

23 Sprinkler requirements IBC NFPA 13 sprinkler system required in nearly all educational facilities regardless of construction type or materials used: Occupancy Groups A-4 & E: If Fire Area Exceeds 12,000 sf If occupant load is 300 or more (A-4 only)

24 Allowable building size IBC Building height increase buildings equipped throughout with an nfpa 13 sprinkler system: can add 1 story and 20 ft to ibc table 503 base values

25 Allowable building size IBC floor area increase buildings equipped throughout with an nfpa 13 sprinkler system: can add 300% (1 story) or 200% (2 or more stories) to ibc table 503 base floor area values

26 Allowable building size IBC area frontage increase buildings with minimum levels of open frontage can add up to 75% to ibc table 503 base floor area values

27 Allowable building size IBC Total building area Total building allowable area = allowable area per floor multiplied by: 2 for 2 story building 3 for 3 or more story buildings

28 Education (e) occupancies with nfpa 13 sprinkler system Construction Type Allowable Limit Allowable building size IBC table 503 IIA IIB IIIA IIIB VA VB Stories Height (ft) Story Total Bldg area (ft 2 ) 125.9k 68.9k 111.6k 68.9k 87.9k 45.1k 2 story total Bldg Area (ft 2 ) 198.8k 108.8k 176.2k 108.8k 138.8k 71.3k 3 or more story total bldg area (ft 2 ) Assumes full frontage increase 298.1k 163.1k 264.4k 163.1k np np

29 Allowable building size IBC table 503 Assembly (a-2,3,4) occupancies with nfpa 13 sprinkler system Construction Type Allowable Limit IIA IIB IIIA IIIB VA VB Stories Height (ft) Story Total Bldg area (ft 2 ) 73.6k 45.1k 66.5k 45.1k 54.6k 28.5k 2 story Total Bldg Area (ft 2 ) 116.2k 71.2k 105k 71.2k 86.2k 45k 3 or more story total bldg area (ft 2 ) Assumes full frontage increase 174.4k 106.9k 157.5k 106.9k 129.4k np

30 Allowable building size IBC & Unlimited area buildings IBC Section 507 gives Unlimited Area Building routes for Type III and IV Construction for: Assembly Education

31 Allowable building size IBC & Unlimited area buildings Provisions for unlimited area buildings rely on open space surrounding building (IBC 507)

32 Allowable building size IBC & Unlimited area buildings Sprinklered: 1 story occupancy: a-4, type iii or iv 1 story occupancy: e, type iiia or iv

33 Allowable building size IBC 508 Mixed occupancy buildings Occupancy 1 (Gym) Occupancy 2 (Classroom wing) Separated vs. non-separated occupancies

34 Allowable building size IBC 508 Non-separated occupancies Occupancy 1 (Gym) Occupancy 2 (Classroom Wing) Most restrictive requirements of all occupancies apply for: Fire Protection Systems (Chapter 9) Allowable Height and Area Other requirements for each portion based upon occupancy of that portion No fire separation between occupancies required* *Hazardous occupancies require separation.

35 Allowable building size IBC 508 separated occupancies Occupancy 1 (Gym) Occupancy 2 (Classroom Wing) Requirements of code for each portion based upon occupancy of that portion Allowable Height of each occupancy based upon construction type and occupancy Allowable Area of each story Sum of actual area over allowable area of each occupancy 1.0

36 Allowable building size IBC table separated occupancies NP = Not Permitted, N = No Separation Required For a & e occupancies: no separation required

37 Allowable building size IBC Educational facilities: A room or space used for assembly purposes that is associated with a Group E occupancy is not considered a separate occupancy. Examples: gymnasium used for school sports; cafeteria used for school meals

38 Allowable building size IBC 706 separate buildings fire walls Each portion of a building Fire Wall per IBC 706 separated by one or more fire walls shall be considered to be a separate building Occupancy 1 Occupancy 2

39 Allowable building size IBC 706 Heights and areas calculator free tool Handles Separated Occupancies Non-Separated Occupancies (Check both )

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41 Construction Type Allowable Limit Allowable building size IBC table 503 IIA IIB IIIA IIIB VA VB Stories Height (ft) Story Total Bldg area (ft 2 ) 125.9k 68.9k 111.6k 68.9k 87.9k 45.1k 2 story Total Bldg Area (ft 2 ) 198.8k 108.8k 176.2k 108.8k 138.8k 71.3k ICC Building Data ($/sf) $180 $172 $161 $153 $140 $136 Education (e) occupancies With nfpa 13 sprinkler & frontage increase 11% cost savings

42 Avg. school building size National averages Size Cost ($/sf) Using ICC Data - Potential 11% Cost Savings Savings Per sf Total Bldg Savings Elem. School 80,000 sf $210 $23/sf $1.8 MM Middle School 117,000 sf $270 $30/sf $3.5 MM High School 154,700 sf $267 $29/sf $4.4 MM can use type va or iiia to accomplish these school sizes! (from top to bottom) Source: school planning & management & aug 2016 icc building valuation data. 11% savings is difference between type IIA and IIIA construction

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44 So, it can be done!

45 Building: combination of spaces and assemblies

46 Space planning What s in a school? small spaces Classrooms bathrooms Offices medium spaces Labs Music room kitchen LARGE SPACES CAFETERIA GYM library

47 Classroom wings School Base Allowable Sizes IBC Table 503

48 Space planning Classroom wings Double-loaded corridor Classrooms: 800 sf min; sf/student Usually square to slightly rect. length no more than 1.5x width Common sizes: 28 x30, 30 x30, 30 x32 Corridor width: 6-18 ft wide, lockers? Min ceiling height: 9 ft. typ flr to flr ~ 13ft Source: texas education agency; Virginia school planning guide

49 School Base Allowable Sizes IBC Table 503 Run through egress requirements

50 egress requirements IBC Egress Requirements in Educational Facilities IBC 2012 Ref. Min. # of Exits 2 (Occupant Load ) Min. Separation of Exits 1/3 of Longest Diagonal Bldg Dimension a Max. Common Path of Egress Travel 75 ft a Table Max. Exit Access Travel Distance 250 ft a Table a: With NFPA 13 Sprinkler System Throughout

51 labs Source: costea photography courtesy lpa inc

52 library

53 cafeteria

54 gymnasium School Base Allowable Sizes IBC Table 503

55 Long spans, open areas Gymns/arenas: 7,000 sf+, ceiling heights: 20 ft+, spans: 60 ft 300 ft+

56 El dorado high school basketball arena El dorado, ar 165 roof span Photo Credit: cadm Architects

57 Saved $60K by changing gym roof from steel to wood Photo Credit: cadm Architects

58 El dorado high school auxiliary gym Photo Credit: cadm Architects

59 Franklin elementary school gym Franklin, wv Photo Credit: Pam Wean, MSES Architects

60 Example large span roof structure o.c. X X Glulam Beam Beam Camber Column Cost /sf 60 10¾ x33 2-3/8 6¾ x7½ $ ¼ x36 3 8¾ x7½ $ ¼ x42 3¼ 8¾ x7½ $ ¼ x48 3½ 8¾ x7½ $ ¼ x54 3¾ 8¾ x7½ $19 Assumes r ll =20 psf; r dl = 20 psf; column height = 24 ft; glulam: df 24f-v4, ½ ROOF SHEATHING

61 Example large span roof structure PARALLEL CHORD 2-0 o.c. X X Glulam Beam Beam Camber Column Cost /sf 60 12¼ x34½ 2-3/8 8¾ x7½ $ ¼ x40½ 2-5/8 8¾ x7½ $ ¼ x46½ 3 8¾ x7½ $ ¼ x54 3 8¾ x9 $ ¼ x60 3-3/8 8¾ x9 $21 Assumes r ll =20 psf; r dl = 20 psf; column height = 24 ft; glulam are df 24f-v4, ½ ROOF SHEATHING

62 Example large span roof structure PARALLEL CHORD 2-0 o.c. X X Glulam Beam Beam Camber Column Cost /sf 60 12¼ x42 2 8¾ x9 $ ¼ x51 2 8¾ x9 $ ¼ x58½ 2¼ 8¾ x9 $ ¼ x66 2½ 8¾ x10½ $ ¼ x73½ 2¾ 8¾ x10½ $18 Assumes r ll =20 psf; r dl = 20 psf; column height = 24 ft; glulam are df 24f-v4, ½ ROOF SHEATHING

63 Double scissor 8 o.c. span = 75 ft Photo Credit: redbuilt Taylor middle school cafeteria Millbrae, ca

64 El dorado high school commons Photo Credit: cadm Architects

65 Albert lea high school lobby Albert lea, mn

66 Cost: Middle School $130/sf Lower School $112/sf Photo Credit: dtw architects & planners Duke lower & middle school library Durham, nc

67 Building: combination of spaces & assemblies Fire Resistance Occupant Comfort Durability Structural Assembly Performance MEP, Data, Comm.

68 Building: combination of spaces & Fire resistance assemblies

69 Fire resistance detailing IBC 601 Key Differences in Fire Ratings for Construction Types IIIA IIIB VA VB Exterior Wall FRT FRT No FRT No FRT Exterior Bearing Wall 2 hr 2 hr 1 hr 0 hr Exterior (Non-Bearing) Wall 1 or 0. See IBC Table 602 Interior Bearing Wall 1 hr 0 hr 1 hr 0 hr Roof Assembly 1 hr 0 hr 1 hr 0 hr Floor Assembly 1 hr 0 hr 1 hr 0 hr IBC Table 601 Note: FRT = Fire Retardant Treated

70 Fire resistance detailing IBC & 721 Ibc & lists many options for demonstrating fire resistance ratings: Prescriptive designs of IBC Section 721 and Tables 721.1(2) [Walls] and 721.1(3) [Floors and Roofs].

71 Demonstrating fire resistance ratings: Calculated designs of IBC Section 722. IBC Section can be used for assemblies requiring 1-hour ratings or less. Fire resistance detailing IBC & 722.6

72 Tested assemblies (ASTM E119): UL Listings Gypsum Catalog Manufacturer s catalogs Other sources Fire resistance detailing IBC 703.2

73 Commonly Approved Sources: American Wood Council s DCA3: Fire-Rated Wood- Frame Wall and Floor/Ceiling Assemblies APA s Document W305 Fire-Rated Systems. SBCA s Metal Plate Connected Wood Truss Handbook Section 17 Fire Performance of Trusses Fire resistance detailing IBC 721 & 722 An UL Assembly listed by the Underwriters Laboratory is only ONE of MANY routes to compliance with fire ratings.

74 Other methods of demonstrating fire resistance ratings: Fire-resistance designs documented in sources Engineering analysis based on a comparison Fire-resistance designs certified by an approved agency 3rd Party Testing Reports Fire resistance detailing Ibc 703.3

75 Fire resistance detailing IBC 722 For Exposed Wood Members: IBC References AWC s NDS Chapter 16 (AWC s TR 10 is a design aid to NDS Chapter 16)

76 Exposed wood fire resistance Fire resistance detailing Nds chapter 16 Assumptions: Nominal assumed char rate = 1.5 /hr. Structurally spanning members: reduced section checked for capacity vs. demand Source: AWC s TR 10

77 Can include WSP in assemblies which were tested without them: ESR 2586 AWC s DCA4 Gypsum Association Manual Fire resistance detailing Adding wsp to fire rated walls GA Fire Resistance Design Manual item 23 in Section 1 of the General Explanatory Notes: "When not specified as a component of a fire- resistance rated wall or partition system, wood structural panels shall be permitted to be added to one or both sides. ESR 2586:

78 Fire resistance detailing Ibc Type iii construction requires exterior walls to be fire retardant treated framing

79 Fire resistance detailing Using frt lumber in fire rated walls Wood stud walls may contain fire-retardant-treated studs as well as untreated wood studs. The use of fireretardant-treated plywood (wood structural panels) may be used in Designs that contain use of untreated plywood when all other specified attributes are equivalent to the wood structural panel used in the Design.

80 Fire resistance detailing Ibc Type iii exterior bearing walls require 2 hr rating. In many cases, hourly rating is only required from inside of wall.

81 acoustical detailing

82 Air-borne sound: Sound Transmission Class (STC) Measures how effectively an assembly isolates air-borne sound and reduces the level that passes from one side to the other acoustical detailing IBC 1207 Structure-borne sound: Impact Insulation Class (IIC) Evaluates how effectively an assembly blocks impact sound from passing through it

83 acoustical criteria IBC 1207 No code requirements for education buildings, but many owners require minimum level of performance Code requirements for residential occupancies: Min. STC of 50 (45 if field tested): Walls, Partitions, and Floor/Ceiling Assemblies Min. IIC of 50 (45 if field tested) for: Floor/Ceiling Assemblies

84 acoustical criteria Ansi s12.60: Optional acoustics criteria for schools Examples: Floor/wall separating learning space from corridor: stc 45 Floor/wall separating learning space from music room: stc 60

85 acoustical detailing Many available free online STC & IIC rated assembly charts (USG, GP, others)

86 acoustical detailing

87 Lightweight concrete topping or other similar materials can provide improved acoustical performance, increased durability acoustical detailing

88 Acoustical mat often used to increase performance. Typically installed between subfloor and topping acoustical detailing

89 Resilient channels Batt insulation acoustical detailing

90 acoustical detailing good detailing + good installation = performance Open leg should be up on walls

91 acoustical detailing

92 acoustical detailing

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94 Durability detailing Durability design goals include minimal maintenance and repairs while maintaining safety. Consider high-traffic areas and areas of high moisture. plan finishes, details accordingly Corridors Bathrooms Entries Labs Kitchen Building envelope

95 Durability detailing Higher durability finishes in high traffic areas Photo: cadm architecture

96 Impact resistant finishes on walls Durability detailing

97 Durability detailing Wood structural panel as backing to finish If also needed for shearwall, consider appropriate side of wall higher traffic

98 Durability detailing 5 8" TYPE X GWB OR IMPACT- RESISTANT PANELS WOOD STRUCTURAL PANELS AS NEEDED AT SHEAR WALLS 5 8 " TYPE X GWB PRESERVATIVE TREATED SOLE PLATE 6" MIN

99 Durability detailing Building envelope functions: Control: heat flow Air flow Vapor diffusion Water penetration Solar, wind, condensation, fire Be durable & maintainable Look good!

100 Durability detailing

101 The perfect assembly: structure is warm & dry Durability detailing

102 Durability detailing Continuity of control layers is critical to envelope performance

103 Durability detailing Applicable to Mixed-humid Hot-humid Mixed-dry Hot-dry Marine Some colder regions (5/6) Source: Building Science Corporation NOT applicable to: Very cold Subarctic/arctic

104 Durability detailing Applicable to: Cold Very cold Source: Building Science Corporation NOT Applicable to Marine Mixed-humid Hot-humid Mixed-dry Hot-dry Subarctic/arctic

105 Source: mahlum architects Durability detailing Thermal benefits of wood framing

106 Controlling termites Durability detailing

107 Subterranean Termites Their Prevention and Control in Buildings, US Forest Service 2006 Durability detailing Controlling termites

108 Durability detailing The 6S Approach to Subterranean Termite Control Suppression Site Management Soil and Physical Barriers Slab and Foundation Details Structural Protection Surveillance and Remediation

109 Durability detailing Remove from site tree stumps all wood/cellulose containing debris Formwork (don t leave embedded in foundation) Soil Work Do not use excavation spoil under wood frame elements Drain water away from building (slope 5% for 10 ) Keep non-treated wood away from soil (6-8 code minimums)

110 Durability detailing Example termite mud tube

111 Physical Barriers Durability detailing 4 thick sand or crushed stone (1/16-1/10 Dia) beneath slab and/or along inside and outside of foundation wall Install sheet metal between top of foundation and sill plate Wrap perimeter foundation in mesh to protect at/below grade penetrations (1/32 grid spacing) Marine grade stainless steel mesh has 20yr service life Openings in slab/stem wall sealed with non-shrink grout Slabs and Foundations Slabs control joints and cracks do not exceed 1/25 Stem walls exposed for 8 above grade to allow inspection Keep crawl space access in floor instead of foundation walls

112 Durability detailing Wood Wall Ground clearance: Wood wall Ground clearance: Wood column Wood Post 8-12 Min. Moisture barrier 8-12 Min. Moisture barrier

113 Structural design Can wood be cost effectively used in floor and roof assemblies for classroom wings?

114 Structural design Educational facilities will generally be risk category iii buildings Increases design loads: Wind 10% Seismic 25% Snow 10%

115 Structural design Common Loadings: Classroom Floor Live Load: 40 psf Corridor Floor Live Load: 80/100 psf Common Wood Frame Floor Dead Load: psf 26 ft 32 ft spans: Deep I-Joists or Parallel Chord 16 o.c.

116 Structural design Asce Live load reduction Live load reduction classroom floor framing member\grid 25 x25 30 x30 32 x32 Exterior column 27 psf 24 psf 23 psf Interior column 22 psf 20 psf 20 psf Exterior beam 34 psf 30 psf 29 psf Interior Beam 27 psf 24 psf 23 psf Based on classroom live load 40 psf. Max. reduction = 0.50 L

117 Vibration control school floor spans in the range work well from a layout perspective. Floor design of wood members in this span range are often governed by vibration and/or deflection control, not structural capacity. Structural design Live Load Deflection Chart, Courtesy: Redbuilt

118 Tools available to designers Structural design Vibration control Vibration Analysis: FP Innovations (Spreadsheet available upon request) Joist Manufacturer s Rating Systems

119 Floor framing options Typical Corridor Typical Unit or Classroom Example classroom wing floor plan

120 Example classroom wing floor plan Floor framing options

121 steel grid: Concrete slab Steel deck Steel joists Steel wide flange beams Floor framing options Wood grid: LW Concrete topping Wood Floor sheathing Wood Trusses/i-joists Glulam beams

122 Grid Dim. Floor framing options Approximate Member Sizes Floor Framing Girders Grid Steel Beam Glulam Beam 25 x25 W21x55 8-3/4 x27 30 x30 W27x /4 x33 32 x32 W30x /4 x36 Grid Dim. Note: All member sizing needs to be confirmed by a licensed engineer for conditions of your project. Assumptions: LL = 65 psf, DL = 30 psf (Wood), DL = 70 psf (Steel)

123 Grid Dim. Floor framing options Approximate classroom Member Sizes Floor Framing Joists Grid Steel Joists Wood Trusses/I-Joists 25 x x x Grid Dim. Note: All member sizing needs to be confirmed by a licensed engineer for conditions of your project. Assumptions: LL = 65 psf, DL = 30 psf (Wood), DL = 70 psf (Steel)

124 Floor framing options

125 Floor framing options Wood Bearing Wall

126 Floor framing options Wood Bearing Wall

127 Floor framing options Corridor floor framing often shallower than adjacent rooms: accommodate main MEP runs, shorter spans Approximate Max Corridor Width for Solid Sawn Floor Framing 24 2x x x x SPF #2, DL = 30, LL = 100

128 mep detailing Accommodating mep & data needs in schools with wood framed assemblies

129 mep detailing Effect of framing layout on mep Installation ease Access for future needs

130 mep detailing Mep opportunities in Paralllel chord trusses Source: mitek

131 mep detailing Mep opportunities in i-joists Source: weyerhaeuser

132 Sprinklers in floors/roofs Concealed spaces such as floor/ceiling and roof/ceiling assemblies may require sprinkler protection Nfpa 13 section lists opportunities for sprinklers to be omitted from concealed spaces

133 Sprinklers in floors/roofs Nfpa In combustible construction, several methods for eliminating need for sprinklers in floors/roofs: When ceiling is directly attached to framing or channels: Draftstop floor into volumes < 160 ft 3 also need 3-1/2 batt insulation Fill floor depth with non-combustible insulation When ceiling is dropped: Noncombustible insulation from ceiling to underside of joist, draftstop joist space into volumes < 160 ft 3

134 Floor assembly: 1-1/2 light-weight concrete topping Acoustical mat ¾ floor sheathing Floor framing (trusses, solid sawn or 16 o.c. 6 Batt insulation Resilient channels 5/8 type c gypsum 1 hr Stc50 min. Assembly design

135 9'-0" - ROOFING MEMBRANE - PROTECTION BOARD (IF NEEDED) - XPS RIGID INSULATION (4" (R-20) & 6" (R-30) OPTIONS) OR BATT INSULATION (12" (R-38) & 16" (R-49) OPTIONS) 5-8" WOOD STRUCTURAL PANEL ROOF SHEATHING - 18" DEEP OPEN WEB 2'-0" O.C. - 2 LAYERS 58" TYPE X GYPSUM BOARD - SUSPENDED CEILING 9'-0" 13'-0" 4'-0" 26'-0" 13'-0" 4'-0" 30'-0" - 121" LIGHT WEIGHT CONCRETE FLOOR TOPPING - ACOUSTICAL MAT " WOOD STRUCTURAL PANEL FLOOR SHEATHING - 24" DEEP OPEN WEB 16" O.C. - 6" FIBERGLASS BATT INSULATION - RESILIENT 12" O.C. - 58" TYPE C GYPSUM BOARD - SUSPENDED CEILING

136 Structural design Wall framing Wall design: Common floor to floor in classrooms & admin: 12 ft - 14 ft 16 o.c. is common at exterior walls Interior walls commonly 2x4 or 2x6: single wall, staggered wall or double wall Combined axial & out-of plane bending

137 Tall wall framing Bethel school district, wa: Typically use deep lsl studs to frame gym walls Example tall wall design: Corte Madera, CA 25 Wall Height ASD Wind: C&C: 30 psf; MWFRS: 21.7 psf Non Load-Bearing Studs L/240 Deflection Criteria Stud Option 2x12 DF-L o.c x o.c. 2x10 DF-L 12 o.c x o.c x10.5 DF 19.2 o.c. Material Cost $60/lf $72.50/lf $80/lf $95/lf N/A

138 Seismic advantages of wood framed lateral system: Lighter weight Higher seismic response coefficient, r Results in lower seismic forces Seismic differences in a 2 story, 80 x210 classroom wing Structural design Asce 7-10 chapter 12 wood Steel masonry Seismic r Seismic weight 1815 kips 2487 kips 3170 kips Seismic base shear 25 kips 73 kips 140 kips Asd forces with i=1.25, assumes s ds = 0.10 per Dallas, tx

139 Seismic advantages of wood framed lateral system: Lighter weight Higher seismic response coefficient, r Results in lower seismic forces Seismic differences in a 2 story, 80 x210 classroom wing Structural design Asce 7-10 chapter 12 wood Steel masonry masonry Seismic r Seismic weight 1815 kips 2487 kips 3170 kips 3170 kips Seismic base shear 244 kips 725 kips 555 kips 1,387 kips Asd forces with i=1.25, assumes s ds = 1.0 per Oakland, ca

140 Structural design Lateral framing: shearwalls & diaphragms windspeed.atcouncil.org

141 Shearwall capacity Structural design Sdpwstable 4.3a Divide Nominal Values by 2.0 for ASD Capacity Multiply Nominal Values by 0.8 for LRFD Capacity

142 Perforated Walls Shearwall types Structural design Sdpws 4.3 Solid or Segmented Walls Force Transfer Around Openings Walls

143 Structural design Sdpws 4.3 Likely using a combination of shearwall types: Solid walls at classroom separation Perforated or ftao at corridor and exterior Segmented wall: 2 separate walls, each 6 long 4 hold downs perforated wall: 1 wall, 18 long but only 12 is effective for shear resistance. reduce capacity by c o factor (sdpws ) 2 hold downs

144 Shearwall capacity 15/32 wood structural panels 3 o.c. boundary nails Structural design Sdpws tables 4.3a & 4.3c 630 plf single sided (wind) 450 plf single sided (seismic) 1260 plf double sided (wind) 900 plf double sided (Seismic) 1/2 gypsum No. 6 drywall 4 o.c. 142 plf single sided (wind)

145 Wind design: 2 story, 80 x210 classroom wing 120 mph, exposure c, 13 tall walls, lower wall design each classroom wall is shearwall, 30 o.c. If only one n-s classroom wall is used: force to each wall = 385 plf; 4 o.c. If all classroom walls are used: force to each wall = 193 plf; 6 o.c. Shearwall options Hold down forces: 6,670 lb (only one n-s wall) 3,340 lb (all n-s walls) Can be accomplished with standard light frame wood construction Wood Bearing Wall & Shear Wall

146 Wind design: 2 story, 80 x210 classroom wing Shearwall options 120 mph, exposure c, 13 tall walls, lower wall design corridor walls and exterior walls are shearwalls If only one corridor wall is used: force to wall = 336 plf; 6 o.c. (only need 40 ft of solid wall) If both corridor walls are used: force to each wall = 336 plf; 6 o.c. (only need 25 ft of solid wall) Hold down forces: 5,780 lb Can be accomplished with standard light frame wood construction Wood Bearing Wall & Shear Wall

147 High seismic design: 2 story, 80 x210 classroom wing Shearwall options S ds = 1.0, 13 tall walls, lower wall design each classroom wall is shearwall, 30 o.c. If all classroom walls are used: force to each wall = 580 plf; 2 o.c. (single sided) or 4 o.c. double sided Hold down forces: 11,600 lb (all n-s walls) Can be accomplished with standard light frame wood construction Wood Bearing Wall & Shear Wall

148 High seismic design: 2 story, 80 x210 classroom wing S ds = 1.0, 13 tall walls, lower wall design corridor walls and exterior walls are shearwalls If both corridor walls are used: force to each wall = 363 plf; 3 o.c. Shearwall options Hold down forces: 7,250 lb Can be accomplished with standard light frame wood construction Wood Bearing Wall & Shear Wall

149 Wall framing options Wall design comparison Wood sheathed shearwall/bearing wall Structural steel frame w/non-bearing cold formed steel studs

150 Cost comparison wall framing 118 long section of wall in 2 story bldg Wall framing options material Wall framing Lateral framing wall structure cost wood 2x6@16 bearing Wood structural panel shearwalls $11.00/sf steel 16 non-bearing Structural steel braces $14.30/sf Source: rs means 2016 q2 data, chicago, il region Costs Include wall framing, opening framing, exterior wall sheathing & lateral framing components

151 School Base Allowable Sizes IBC Table 503 Case Studies

152 Source: redbuilt School Base Allowable Sizes IBC Table 503 Los Angeles school #1

153 Source: redbuilt Los Angeles school #1 Typical floor construction: Spans = ft 36 deep open web hybrid wood o.c.

154 Source: CADM Architecture

155 Source: CADM Architecture El dorado high school CADM ARCHITECTURE, INC. EL DORADO, ARKANSAS 62 acre Project Site 1,600 Student Capacity 322,500 Total Area $43.3 M Construction Cost $ Construction Cost / SF

156 El dorado high school During the early pre-construction stages, the Architect worked with the construction manager to evaluate various systems structural steel, pre-cast concrete and wood versus steel framing and ultimately made the decision to maximize the use of wood framing throughout the project. By just changing the framing, we were able to save about $2.7 million, which was five percent of that original $60 million budget. Blake Dunn, CADM Architects

157 El dorado high school Source: CADM Architecture STC-48 STC-47

158 El dorado high school Stc 49 Source: CADM Architecture

159 Classroom wing framing El dorado high school Source: CADM Architecture

160 Example School Floor Classroom Construction wing framing Source: CADM Architecture

161 Gunter primary school Gunter, tx COMPLETED ,000 SF; $100 / SF Type VB construction

162 Vista academy Humble, tx COMPLETED ,700 SF, 2 stories; type va construction; $64/sf Source: robert burnham, rwba

163 Questions? This concludes The American Institute of Architects Continuing Education Systems Course WoodWorks

164 Copyright Materials This presentation is protected by US and International Copyright laws. Reproduction, distribution, display and use of the presentation without written permission of the speaker is prohibited. The Wood Products Council 2016