Copyright Materials. Learning Objectives. Design is in the Details: Solutions to Common to Mid Rise Design. Challenges

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1 Design is in the Details: Solutions to Common to Mid Rise Design Challenges The Wood Products Council is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program 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 program 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. Matthew S. Church P.E. Davis & Church, LLC Alpharetta, Georgia Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation. Learning Objectives 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. At the end of this program, participants will better understand: The inherent differences between the Types of Construction that utilize the Types that utilize wood as the primary structural system. The requirements and affects of using fire retardant treated lumber in Type 3 multi multi story wood construction. Possible detailing solutions for securing and maintaining various fire rated wall and floor assembly requirements The potential benefits of using Cross Laminated Timber in mid rise wood structures. How to approach the design of multi story wood structures in ways that increase efficiency and productivity throughout the design and construction phases of a project. The Wood Products Council 2013

2 2009 IBC Construction Types Fire Retardant Treated Wood (FRT) Type V. Type V construction is that type of construction in which the structural elements, exterior walls and interior walls are elements exterior walls and interior walls are of any materials permitted by this code Type IV. Type IV construction (Heavy Timber, HT) is that type of construction in which the exterior walls are of noncombustible materials and the interior building elements are of solid or laminated wood without concealed spaces. Fire retardant treated wood framing complying with Section shall be permitted i ith ti 2 h ll itt d within exterior wall assemblies of a 2 hour rating or less Type III. Type III construction is that type of construction in which the exterior walls are of noncombustible materials and the interior building elements are of any material permitted by this code. Fire retardant treated wood framing complying with Section shall be permitted within exterior wall assemblies of a 2 hour 2 i hi i bli 2 h rating or less. Section Fire retardant treated wood. Fire retardant treated wood is any wood product which, when impregnated with chemicals which when impregnated with chemicals by a pressure process or other means during manufacture, shall have, when tested in accordance with ASTM E 84 or UL 723, a listed flame spread index of 25 or less and show no evidence of significant or less and show no evidence significant progressive combustion when the test is continued for an additional 20 minute period. Additionally, the flame front shall not progress more than 10.5 feet (3200 mm) beyond the centerline of the burners at any time during the test. FRT Strength Adjustment Factors Building Heights and Areas g Section Strength adjustments. Design values for untreated lumber and wood structural panels, as specified in Section , as specified in shall be adjusted for fire retardant treated wood. Adjustments to design values shall be based on an approved method of investigation that takes into consideration the effects of the anticipated takes the effects of the anticipated temperature and humidity to which the fire retardant treated wood will be subjected, the type of treatment and redrying procedures. Values may vary depending on the manufacturer Group R-1, R-2, R-4 I-1 I-2 M A IBC Table 503 (Partial) TYPE OF CONSTRUCTION Type I Type II Type III Type IV Type V A B A B A B HT A B Max Bldg Feet UL Stories UL Story Area UL UL 24,000 16,000 24,000 16,000 20,500 12,000 7,000 Stories UL Story Area UL 55,000 19,000 10,000 16,500 10,000 18,000 10,500 4,500 Stories UL NP 1 1 NP Story Area UL UL 15,000 11,000 12,000 NP 12,000 9,500 NP Stories UL Story Area UL UL 21,500 12,500 18, ,000 20,500 14,000 9,000 Stories UL Story Area UL UL 155,000 9,500 14,000 9,500 15,000 11,500 6,000

3 Height & Story Increases Section Where a building is equipped throughout with an approved automatic sprinkler system in accordance with Section (NFPA 13 System), the value specified in Table 503 for maximum height is increased by 20 feet and the maximum number of stories is increased by one. These increases are permitted in addition to the area increase in accordance with Sections and d h d For Group R buildings equipped throughout with an approved automatic sprinkler system in accordance with Section (NFPA 13R System), the value specified in Table 503 for maximum the specified in for maximum height is increased by 20 feet and the maximum number of stories is increased by one, but shall not exceed 60 feet or four stories respectively. Table 503 w/ Sprinkler Increases NFPA 13R Sprinkler System TYPE OF CONSTRUCTION Type III Type IV Type V A B HT A B Group Max Bldg Hgt Feet R-1, R-2, R-4 Stories I-1 Stories I-2 Stories 2 NP 2 2 NP M Stories A-2 Stories NFPA 13 Sprinkler System TYPE OF CONSTRUCTION Type III Type IV Type V A B HT A B Group Max Bldg Hgt Feet R-1, R-2, R-4 Stories I-1 Stories I-2 Stories 2 NP 2 2 NP M Stories A-2 Stories College Park Apts College Park, MD 4 Stories of Wood IBC Type 5 Construction 500 Residential Units 2 Stand alone Parking Structures Renaissance at The Quarter Towson, MD 4 Stories of Wood over Podium IBC Type 5 Construction 150 Residential Units Ground Level Parking

4 5 & 6 Stories of Wood IBC Type 3 Construction 200 Residential Units Stand alone Parking Structure 626 Dekalb Atlanta, GA 4 Stories of Wood over Podium IBC Type 5 Construction 110 Residential Units over 1½ Levels of Below Grade Parking 870 Inman Atlanta, GA 4 & 5 Stories of Wood IBC Type 3 Construction 325 Residential Units Stand alone Parking Structure The Enso Atlanta, GA 5 Stories of Wood over 2½ Levels of Parking 149 Residential Units IBC Type 3 Construction Artisan on 18 th Nashville, TN

5 5 Stories of Wood over 3 Levels of Parking 180 Residential Units IBC Type 3 Construction Broadstone Peachtree Atlanta, GA 5 & 6 Stories of Wood IBC Type 3 Construction 272 Residential Units Stand alone Parking Structure The Jane Atlanta, GA 4 & 5 Stories of Wood IBC Type 5 Construction 280 Residential Units Stand alone Parking Structure 23Hundred Nashville, TN 4 & 5 Stories of Wood over 1 Level of Retail & Amenity 300 Residential Units of IBC Type V Construction 1845 Piedmont Rd Atlanta, GA

6 LaGrange Walk LaGrange, IL Fire Resistance Requirements i R i t 5 Stories over Podium with Below Grade Parking 284 Residential Units IBC Type 3A Construction Typical Architectural Floor Plan Typical Wall Framing Plan

7 Typical Floor Framing Plan Fire Resistance Ratings for Exterior Walls Fire Rating Requirements Requirements For Building Elements Fire Rating Requirements Requirements Based on Fire Separation Distance

8 Traditional Platform Framing Type V Top Chord Bearing Floor Truss Type V Filling the cavity solid along top of wall between of truss chords has the following advantages: 1. Provides uniform bearing load along the top of the wall. 2. Eliminates having to align stud packs with floor framing 3. Reduces the number of plys in stud packs py p (i.e. 2 2x4 at 16 in lieu of 3 2x4 at 24 ) Top Chord Bearing Floor Truss Type V Fire Rating Requirements Fire Rating Requirements For Building Elements

9 Fire Resistance Ratings ANSI/UL 263 Fire Resistance Ratings ANSI/UL 263 Fire Resistance Ratings ANSI/UL 263 Fire Resistance Ratings ANSI/UL 263

10 Fire Resistance Ratings ANSI/UL 263 Type III Construction Advantages: Disadvantages: 1. Fire rating continuity 1. Cost of FRT beam 2. Less expensive hanger 2. Added shrinkage from FRT beam d 3. Stability of FRT beam during construction Type III Construction Top Flange Hanger Installed Over Single Layer of 5/8 Gypsum Sheathing Advantages: 1. Less expensive hanger 2. Minimum shrinkage Disadvantages: 1. Lack of fire rating continuity 2. Added cost of FRT ledger 3. Quality control concerns regarding fastening of ledger; particularly with 2x stud backup Simpson Strong-Tie T-TFWALL11

11 Top Flange Hanger Installed Over Single Layer of 5/8 Gypsum Sheathing Type III Construction Ref: Simpson Strong-Tie T-TFWALL11 Advantages: 1. Continuity of fire rating 2. Easier to construct 3. Minimum shrinkage Disadvantages: 1. More expensive hanger 2. Install strip of gypsum during rough framing stage Type III Construction Type III Construction

12 Fire Resistance Ratings Ratings for Exit Enclosure Walls Rated Exit Enclosures Fire Resistance Ratings ANSI/UL 263 Fire Resistance Ratings ANSI/UL 263

13 Type III and V Construction Fire Resistance Ratings i R i for Fire Walls Fire Resistance Ratings ANSI/UL 263 Fire Resistance Ratings ANSI/UL 263

14 Fire Resistance Ratings ANSI/UL 263 Fire Resistance Ratings ANSI/UL 263 Fire Resistance Ratings ANSI/UL 263 Fi R i R i Fire Resistance Ratings for Fire Walls

15 Masonry & Concrete Walls in Wood Structures Type III and V Construction Lateral Force Resisting System (ANSI / AF&PA SDPWS 2008) Section 4.1.5: Wood frame shear walls, wood frame diaphragms, trusses, and other wood members and systems shall not be used to resist seismic forces contributed by masonry or concrete walls in structures over one story in height. one story Exceptions: 1. Allowed where seismic forces contributed by masonry or concrete walls do y not result in torsional force distribution 2. Wood shear walls allowed in 2 story structures provided special requirements are met 3. Allowed to resist seismic forces contributed by other masonry or concrete seismic contributed by other masonry or concrete components, including: chimneys, fireplaces, concrete or masonry veneers and concrete floors (See Section 4.1.6) Type III and V Construction Type III and V Construction

16 Future of Wood Construction in North America Cross Laminated Timber New generation of lightweight and prefabricated systems Consists of wood strips (planks) stacked crosswise on top of each other (glued or nailed) Thicknesses of panels vary from 50 mm to 600 mm CLT is a well established product in Europe with about 10 manufacturers & hundreds of &h d f buildings ranging from single family to mid rise 20 story building in Norway 16 story concept building 9 story building in London CLT vs. Glulam Advantages of CLT Panels Thick Orthotropic Plate Beam like like member Cross lamination minimizes swelling and shrinkage in the board plane Relatively high in plane (seismic) in and out of plane (wind) strength and stiffness properties Has 2 way action capability similar to a concrete slab G dfi i t h ti b Good fire resistance heavy timber construction (inherent fire resistance)

17 Variety of Configurations CLT Floor Panels Up to 4 transverse layers Single or multiple surface layers CLT Wall Panels Additional Advantages of CLT Panels Factory produced with high precision CNC machines Fast on site assembly Panel to panel connections made with traditional wood fasteners Minimal site waste due to prefabrication Health and safety benefits Low environmental footprint

18 CLT in Mid Rise Construction CLT Fire Test Results Test ICC Final Action Hearing Results Where to Begin

19 S 2 Parking Beneath Group R Section Max 1 story parking above grade plane utilizing: 1. Type I construction for enclosed or combination of open and enclosed garage 2. Type I or Type IV for open garage T IV Number of stories used to determine Group R construction type is measured from the floor above type is the floor above parking area Floor assembly between parking and Group R above shall p match construction type for parking level w/ a fire resistance rating not less than the mixed occupancy separation required in Section 508.4required in Potential 6 Stories of Wood per Section Potential all wood building including podium slab RESIDENTIAL RESIDENTIAL RESIDENTIAL RESIDENTIAL RESIDENTIAL PARKING Type III & IV building w/ NFPA 13 sprinkler = up to 85 Type V building w/ NFPA 13 sprinkler = up to 70 up 70 6 Stories of Wood Section hour Rated CLT Fire Walls Group R 1 and R 2 buildings of Type IIIA construction First floor assembly above basement must have a minimum 3 hour fire resistance rating Height increased to 75 feet Floor area subdivided by 2 hour rated fire walls into areas of not more than 3,000 square feet. Additional 335 feet of CLT wall panel At 75 feet tall yields 25,125 GSF of wall panel 15,750 GSF of floor panel or concrete podium Total approx. material cost = $730,110 (plus freight) Less than $8.00/SF of additional overall building cost additional overall STORY 6 STORY 5 STORY 4 STORY 3 STORY 2 STORY 1 BASEMENT

20 ANSI Standard & Design Guide Questions? This concludes The American Institute of Architects Continuing fa i i Education Systems Course Matthew S. Church P.E. Davis & Church, LLC Alpharetta, Georgia church.com