The Momentum of Tall Wood Buildings Presented by, Lisa Podesto, M.S., P.E. Senior Technical Director WoodWorks
The Momentum of Tall Wood Buildings
Presented by,
Lisa Podesto, M.S., P.E.
Senior Technical Director
WoodWorks
“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.
Description
With nearly 20 completed tall wood buildings worldwide and several under design
in the U.S., many architects are curious about the factors creating this momentum
and how design teams are navigating building codes that don’t directly address
the mass timber technologies being used. While pursuing ambitious carbon
reductions and oftentimes a new aesthetic, designers are still tasked with meeting
all of the usual objectives, including a high degree of life safety, building
performance, and cost-effectiveness. This presentation provides context for the
growing trend of using mass timber for mid- and high-rise buildings. Among other
things, it offers insight on available research and testing specifically highlighting
structure, fire, and acoustics using built project examples.
1. Review the historical context for tall wood structures, and consider the
construction and sustainability motivators driving modern examples.
2. Learn how designers of tall wood buildings can achieve objectives outside of
code requirements, including high acoustical performance, unique aesthetics,
and ambitious carbon reductions.
3. Study a range of prescriptive- and performance-based structural design
approaches to tall wood projects.
4. Realize how design teams are seeking to achieve fire performance
requirements necessary for approval in the U.S.
Course / Learning Objectives
Overview
• Defining Tall Wood Terms
• Precedence/Context
• Motivation and Benefit
• Execution Under U.S. Code
� Acoustics
� Structure
� Fire
Overview
Momentum Starts With a Disruption
Mass Timber Building Systems
Mass Timber Building Systems
Images: StructureCraft
1 9 0 6
B UT L E R S QUA RE , MINNEAPOLIS, MN
High-Rise Timber Studies
http://www.woodworks.org/publications-media/research-papers/
Disruption Causes a Ripple
2008 2009 2010 2011 2012
2013 2013 2014 2015 2016
7 Stories 8 Stories/78 ft 8 Stories/87 ft 8 Stories/70 ft 8 Stories/88 ft
9 Stories/92 ft 6 Stories/75 ft 6 Stories/96 ft 14 Stories/163 ft 18 Stories/174’
Mixed Use Tenant Owned Apt. Apartments Apartments Office
Public Housing Office Office/Education/Assembly Apartments Student Housing
GERMANY SWEDEN UK GERMANY AUSTRIA
ITALY SWITZERLAND CANADA NORWAY CANADA
0
5
10
15
20
25
International Tall Wood Projects
http://www.woodskyscrapers.com/projects.html
2 0 0 9S TA DT H A U S LONDON, UK
9 STORIES
Architect:WaughThisleton ArchitectsPhoto Credit:
Designing the World’s Tallest Mixed-Use Buildinghttps://player.vimeo.com/video/74582783
2 0 1 2L C T 1
DORNBIRN, AUSTRIA
8 STORIES88.5 FT
~17 SQ.FT.
ARCHITECT: Hermann KaufmannENGINEER: Merz Kley Partner
LCT One: Case Study of an Eight Story Wood Office Buildinghttps://player.vimeo.com/video/50805125
2 0 1 3FORTE’
MELBOURNE AUSTRALIA10 STORIES
DESIGN BUILDER: Lend LeasePhoto Credit: Lend Lease
2 0 1 5TREET APARTMENTS,
BERGEN, NORWAY14 STORIES
173 FT~63K SQ.FT.
ARCHITECT: ArtecENGINEER: Sweco
ARCHITECT: Acton OstrayENGINEER: Fast & Epp
S T A R T E D N O V E M B E R 2 0 1 5
B R O C K C O M M O N S
BRITISH COLUMBIA, CANADA TallWood House at Brock Commons https://vimeo.com/woodproductscouncil/review/201122225/d69a922674
ARCHITECT: RLP, Prof. Rüdiger Lainer + PartnerENGINEER: RWT, part of Woschitz Group
S T A R T E D 2 0 1 6
H o H o V i e n n a
Vienna, Austria
ARCHITECT: Lever ArchitectureENGINEER: KPFF, Seattle, WA
S T A R T S 2 0 1 7
F R A M E W O R K
Portland, Oregon Webinar- Framework: A US Tall Wood Experience https://vimeo.com/woodproductscouncil/review/205558132/09a0489f68
Survey of International Tall Wood Buildingshttps://vimeo.com/woodproductscouncil/review/121147949/024f53bed0
Ripples Build into Swell
Designers Contractors
Government Industry
Carbon Reduction
Stadhaus, London, UKArchitect: Waugh Thistleton ArchitectsPhoto credit: Waugh Thistleton Architects
Volume of wood used 950 m3
Carbon sequestered and
stored (CO2e)
660
metric tons
Avoided greenhouse gases
(CO2e) 225 metric tons
Total potential carbon
benefit (CO2e) 915 metric tons
Carbon savings from the choice of wood in this one
building are equivalent to:
175 passenger vehicles off the
road for a year
Enough energy to operate a
home for 79 years
Energy Performance
0
100
200
300
400
500
Wood Concrete Steel
Thermal Resistance
*Normalized ComparisonSource: Thermal Performance of Light framed Systems, CWC
Structural Performance Forte’, Victoria Harbor, Melbourne, AustraliaArchitect: Lend Lease
Speed of ConstructionStadhaus, London, UKArchitect: Waugh Thistleton ArchitectsPhoto credit: Waugh Thistleton Architects
http://www.youtube.com/watch?v=tJHeLyFASEI
Aesthetics ARCHITECT: Michael Green ArchitectureENGINEER: Equilibrium EngineeringPHOTO CREDIT:
Dispelling Myths about Wood ProductsUS Forest Lands
U.S. Forest Land
Forest Area in the United States1630-2012
1045
759 760 756 761 744 738 747 749 751 766
0
200
400
600
800
1000
1200
1630 1907 1938 1953 1963 1977 1987 1997 2002 2007 2012
Th
ou
san
d A
cre
s
Source: USDA-Forest Service, US Forest Resource Facts and Historical Trends FS-1035. (2014).
103.7 128.3 163 190 214.3 248 267.8148.5
174.1223.4
244.6 256.4288.5 306.6363.7
363.2346.7
347365.1
395.6398
0
200
400
600
800
1000
1953 1963 1977 1987 1997 2007 2012
Inv
en
tory
(b
illi
on
cu
bic
fe
et)
U.S. Timber Volume on Timber Land
North South West South West
U.S. Forest Land
Source: USDA-Forest Service, US Forest Resource Facts and Historical Trends FS-1035. (2014).
Western U.S. Wild Fire Epidemic
• Fire readiness andsuppression has gone from 20% of the FSbudget in 2001 to 52%in 2015.
• It is not uncommon to spend $1 million perhour fighting fires.
Source: US Forest Service –
http://www.fs.fed.us/about-agency/budget-performance/cost-fire-operations
Inter-Mountain West Insect Devastation
Source: IDS- Insect and Disease Survey
USDA Forest Health Protection
Rural Economy Benefits
And Then the Wave
2 0 1 6
T 3 OFF I CEMINNEAPOLIS, MN
Architect: Michael Green
Images: StructureCraft, MGA
SEATTLE, WA PORTLAND, OR VANCOUVER, WA PORTLAND, OR
PORTLAND, OR PORTLAND, OR PORTLAND, OR MINNEAPOLIS, MN
6 Stories/85 ft 5 Stories 3 Stories/63 ft 5 Stories
5 Stories 6 Stories/ 85 ft 4 Stories 7 Stories/ 85 ft
STC/IIC
Lab Tested Assemblies
CLT Handbook
Other
Field Tested Assemblies
CLT Handbook
Completed projects
Engineered Assembly
1/3 Octave band
Acoustic Quality
Mass Timber Acoustics
Acoustic Assemblies
Acoustic Testing – Floor Assembly
Floor Assembly
• Carpet
• 3/16” Acoustic mat
sound deadening
layer
• ¾” Gypsum concrete
underlayment
• 5 ply CLT
• 5/8” gypsum board
• Resilient channel
• Rockwool insulation
• 5/8” Gypsum Board
Tall Wood Structural Systems
Gravity Framing Styles
Post & BeamTwo-Way
Panel Deck
“Honeycomb”
Bearing Walls
Lateral Force Systems
Tall Wood Structural Systems
Model Building Code Acceptance
2015 International Building Code
CLT Product Reports
ICC-ES Acceptance Criteria AC 455
Standardizes In-plane Panel Shear Strength
for use in Floor and Roof Decks
Tall Wood Structural Systems
Gravity Framing Styles
Lateral Force Systems
Vertical Lateral/Seismic Force Resisting
Systems
Horizontal Lateral/Seismic Force Resisting
Systems
Tall Wood Structural Systems
CLT Seismic Force Resisting Systems Not addressed In
Seismic Design
ASCE/SEI 7-10 SDPWS 2015
Code Compliance Pathway – ASCE 7-10
Authoritative Documents – eg. ASCE 41-13
EQUIVALENCY
CLT Post Tensioned Rocking Shear Wall
Heavy Timber Buckling-Restrained Brace
© Arup North America Ltd. Distribution and Reproduction By Permission Only
2021 IBC Code Change Proposal
Current Code Alternate Means
Approach
Equivalent to Type IA or IB
Fully EncasedExposed with
trade-offs
Variation to Type IIIA or IV
Exceeding overall building height
<5/6 stories
Exceeding number of stories
<85’
Tall Wood Fire Approach Options
Building Height Limits in Timber
Source: Arup
Fire Life Safety Under U.S. Code
Construction
Type
IA IB IIIA IV
Stories1 UL 12 6 6
Height1(ft) UL 180 85 85
Story Area2 (ft2) UL UL 85.5k 108k
Total Building Area3 (ft2)
UL UL 256.5k 324k
Based on IBC 2012 Table 503 w/ allowable increases
Multi-Story Business Occupancy (B)
1 Assumes NFPA 13 sprinklers throughout (IBC 504.2)2 Assumes NFPA 13 sprinklers throughout (IBC 506.3)3 Assumes 3 or more number of stories (IBC 506.4)
Key Differences in Fire Ratings for Construction Types (hrs)
IA IB IIIA IV
Primary Structural Frame 3 2 1 HT
Exterior wall fire rating 3 2 2 2
Floor assembly fire rating 2 2 1 HT
Fire wall rating 3 3 3 3
Fire Resistance Ratings
IBC Tables 601 & 706.4
Fire Performance
Co
mb
ust
ibil
ity
Fire Resistance
Flame Spread
Classification
Fire Testing
Test Description Testing Agency
Fire Resistive Component Testing –E119 Fire
FPInnovations/ NRC / Southwest
Research Institute/ Independent Labs
Full Scale Encased Compartment Comparison Testing
NRC - CNRC
Full-scale Mass Timber Shaft Demonstration Fire
NRC- CNRC/ FPInnovations
Flame Spread Testing FPInnovations/ Independent Labs
System Fire Resistance Testing – US Demonstration Project
Southwest Research Institute
Penetration Testing FPInnovations
Full Tested Assemblies – E119 Fire Underwriters Labratroy