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