AIA 2016 - The Momentum of Tall Wood Buildings

The Momentum of

Tall Wood Buildings

2016 AIA National Convention

This presentation is protected by U.S.

and international copyright laws.

Reproduction, distribution, display and

use of the presentation without written

permission of the speakers is

prohibited.

This program is registered with the AIA/CES for continuing

professional education. As such, it does not include content that

may be deemed or construed to constitute approval, sponsorship

or endorsement by the AIA of any method, product, service,

enterprise or organization.

The statements expressed by speakers, panelists, and other

participants reflect their own views and do not necessarily reflect

the views or positions of The American Institute of Architects, or

of AIA components, or those of their respective officers,

directors, members, employees, or other organizations, groups

or individuals associated with them.

Questions related to specific products and services may be

addressed at the conclusion of this presentation.

Overview

• Defining Tall Wood

• Precedence/Context

• Motivation and Benefit

• Execution Under U.S. Code

Overview





The momentum of tall wood really started with an disrupter of sorts. Technology has been the great disrupter of the times, hasn’t it? It is no different in the building industry. Advances in materials and manufacturing science has really opened the door for timber products. The disruptive technology in this case is the emergence of Mass Timber building Systems.

Momentum Starts With a Disruption

Some of you may have heard the term mass timber used. While mass timber doesn’t have an official definition, it’s most easily described as construction consisting of solid timber panels. Everyone is familiar with traditional wood construction methods of Post and Beam/Heavy Timber and light frame. Post and beam was a vertical load carrying system of large solid sawn lumber elements as used in floor deck, joist/beam and column and evolved to include glue laminated beams as well. Light frame came about as a very material efficient system that enable smaller wood elements to be used providing both vertical and lateral load resistance. Modern light frame buildings use a whole host of engineered technologies like I-joists, LVL, OSB, plywood, etc. Mass timber building systems make use of small dimension lumber but on a much more “massive” scale providing much higher structural capacity and the advantages that come with heavy timber sizing in regards to fire.

Mass Timber Building Systems

You are familiar with a variety of engineered lumber products such as glulam, LVL, PSL, LSL. These products have been limited to single element beam like applications. In mass timber buildings we use these technologies a little differently. We are using them as panels. These panels can be used horizontally or vertically and provide both the vertical and lateral load resisting capabilities.

Other mass timber systems include cross laminated timber with orthogonal layers of 2x material layered and glued or mechanically fastened together, nail laminated timber and a whole host of timber concrete composites. The advent of CLT is what opened the eyes of designers and industry alike to the potential of timber panels with multi-directional capacity.

NLT isn’t really new either. 2x’s nailed together in the vertical orientation was a common decking system in historical post and beam construction and is making a comeback as a solid timber panel system being prefabricated 8’ wide sections..

Mass Timber Building Systems

Images: StructureCraft

Here is an example of mass timber building; the Redstone Arsenal Hotel in Alabama. This is an all CLT building; floors, exterior walls, floors/roofs and even shafts. As a 4 story Type III building, this is an application that can be done under the current prescriptive building code.

When you consider that most wood structures are less than 3 stories tall, this could be called a tall timber building although it’s probably not really what most people think of when they think of tall timber.

2 0 1 5

REDST O NE ARSENAL CANDLEW O O D

SUIT ES HO T EL

HUNSTVILLE, AL

Design/Build: LendLeaseImages: LendLease

This might be a more representative example of what is often referred to as tall timber. This particular example is a 7-story office building under construction in Minneapolis. This project uses NLT floors with glulam beams and columns and is an example of a timber hybrid using a combination of mass timber and post and beam systems. T3 demonstrates maximization of current code allowances using a prescribed 6 story office occupancy maximum for Type IV construction over a single story Type IA concrete podium, all under the 85’ height limit.

Tall timber is a term that includes both code compliant mid-rise structures such as this as well as high-rise structures that are beyond code.

T3 (Timber/Technology/Transit), Minneapolis, MN• Concept at this point, will know in spring 2015 if they are building it• Surface parking • Hines development unveiled plans for new office building• 7 stories• 210 K sf• 1s t story concrete• Solid wood core

U N D E R C O N S T R U C T I O N

T 3 O F F ICE

MINNEAPOLIS, MN

Architect: Michael GreenImages: StructureCraft, MGA

There have been several published structural concepts for full timber high rise buildings that explore the use of these mass timber systems and can be very useful in understanding how this could be possible.

If people are contemplating 20-40 stories of mass timber construction, it might change the way you feel about doing 6.

High-Rise Timber Studies

High-Rise Timber Studies

typical two bedroom example

Modular CLT

• Preliminary Findings

– Cost with “surface” CLT opportunities

$0

$10

$20

$30

$40

$50

Wood Concrete Modular CLT

65'

85'

125'

Modular CLT

Source: Sellen Construction

Overview





We built 9 stories of wood in the US a hundred years ago. Butler Bros building in Minneapolis, Minn. was a 500,000 sf warehouse originally housing the Butler Bros mail order business. Since then has been converted into a mixed use building with both office and retail.

These relics of the 18th century exist all over the North America; in Boston, San Francisco, Seattle, Vancouver and Toronto; in good condition and in some adaptive reuse application converted from warehouse or factory.

Heavy timber post and beam construction provided the 300 pound per square foot loading requirements of the warehouse. Precut and put together on a module measuring approximately 14' by 16'. The columns which receive the beams with cast iron brackets, gradually diminish in size from 24" square on the ground floor to a spindly 9" on the ninth floor.

1 9 0 6

BUT LER SQ UARE,

MINNEAPOLIS, MN

The mass timber technologies have sent a ripple into the world of construction. We have been watching the ripple effect growing in Europe for almost the past 10 years.

Disruption Causes a Ripple

GERMANY SWEDEN UK GERMANY AUSTRIA

ITALY SWITZERLAND CANADA NORWAY

2008 2009 2010 2011 2012

2013 2013 2014 2015

7 Stories 8 Stories/78 ft 8 Stories/87 ft 8 Stories/70 ft 8 Stories/88 ft

Mixed Use Tenant Owned Apt. Apartments Apartments Office

22

8 storey prototype built in Austria and studies underway for several others in US & Germany.

Lifecycle Tower 2008 - Austria

23

45 x 30m footprint8.1m or 9.45m span from core to perimeter for multi-usePerimeter wood cols at 2.7m (to fit in with 1.35 grid for mixed use dev); 480 x 250

Structure and Fire Testing

24

RC core8.1 x 2.7m panels

CREE by Rhomberg2 0 1 2

LCT O NE

DORNBIRN, AUSTRIA

25

In addition, the facade has been brought to site in 12m-long units including insulation, framing, plasterboard and windows with only the recycled metal cladding added to the elevations on site. Al rainscreen installed on site.

LCT One - Prefabrication

26

The inclusion of the various prefabricated elements has resulted in a construction process with a claimed reduction of one half in resource use through constructional optimisation and claimed reduction in weight of 30% over a purely reinforced concrete structure. Most remarkably the floors were assembled by a site team of five workers at a speed of one floor per day.

LCT One – Construction

US Tall Wood Competition

• Originally a $2 million Project Competition

• So many high quality submissions resulted in 2 projects awarded $1.5 million each

• Funding provided by joint effort between Softwood Lumber Board, Binational Softwood Lumber Council and USDA

• Learn more at rethinkwood.com (LINK HERE)

Framework: An Urban + Rural Ecology

Beneficial State Bancorp will provide site control to real estate developer project, affordable housing investor Home Forward, and LEVER Architecture, for the proposed Framework as a redevelopment of their Pearl District property in Portland, Oregon. The 12-story urban + rural

ecological project is to be constructed primarily of cross-laminated timber (CLT) and will support a distinct blend of functions including street-level retail, office, workforce housing and community space. The main community space is designed to include a public Tall Wood Exhibit,

featuring resources related to the realization and design of the building.

“We consider Framework to be a totally transformative, mission-driven project that will promote social justice,

environmental well-being and economic opportunity at the building, regional and national levels,” said Kat Taylor, Pres ident, Beneficial State Bancorp, the landowner of the project s ite.

“The relationship of our ci ties to our rural communities, what we call ‘forest to frame,’ is strengthened by Framework,” added Tom Cody, Principal, project^. “On a national scale this project will be catalytic, leading to more ta l l wood buildings, driving more wood products and wood product innovation, and boosting rural economic development.”

Tall Wood Winner – Portland, OR

Framework: An Urban + Rural Ecology

Location: Pearl District, Portland, OR

Height: 130’ / 12 stories

Total Building Area: 90,000 square feet

Building Uses: Ground floor retail; 5 office

floors; 5 apartment floors; rooftop amenity

Materials: Cross laminated timber floors and

lateral force resisting system; glued laminated

beams and columns

Projected Completion Date: December 2017

OWNER: Beneficial State Bancorp

ARCHITECT: LEVER Architecture

ENGINEERS: Arup, KPFF Consulting

Engineers and PAE Consulting Engineers

Framework,

Portland, OR

130-134

Holdings, NYCFramework,

Portland, OR

475 West 18th: Setting the Stage For Innovation, Engineering and Architecture130-134 Holdings LLC, in partnership with Spiritos Properties, SHoP Architects, Arup, IcorAssociates, and environmental consultancy Atelier Ten, proposed 475 West 18th as a transformative and sustainable prototype for the design and construction industry,

demonstrating an innovative approach to going beyond a limited palette of materials and systems for high-rise construction. Expanding the palette with wood, a locally sourced and renewable material, provides a low-carbon, more economically sound building solution.

475 West 18th’s extensive use of wood structural elements and other wood products allows

the team to set ambitious sustainability targets in the building's design, construction, and operation. By combining aggressive load reduction with energy efficient systems, the project team anticipates reducing overall energy consumption by at least 50 percent relative to current energy codes. It will also target LEED Platinum certification, as well as pursue higher levels of sustainability not captured in the LEED system.

“By choosing to develop a timber building, we hope to pave the way for a new method of urban construction that is ecologically conscious and supportive of rural economies,” said Erica Spiritos of Spiritos Properties. “Rooted in the forests and erected in the city, this building is a celebration of habitats that are at once ancient and cutting edge, interconnected and

individual, natural and technological.”

“We are delighted to be developing this tall timber building in New York City, which has led the world in urban design and engineering throughout the last century,” said Jonathan Ghassemi, on behalf of 130-134 Holdings LLC. “We are confident that this project will once again position

New York to serve as a leader in a new generation of sustainable building methods during the 21st century and beyond.”

Tall Wood Winner – New York, NY

475 West 18th: Setting the Stage for

Innovation, Engineering and Architecture

Location: West Chelsea, Manhattan, NY

Height: 120’ / 10 stories

Total Building Area: 50,000 square feet

Building Uses: Residential condominium

with ground floor commercial space

Materials: Mass timber columns, beams,

shear walls and floors

Projected Construction Start Date: Fall

2016

OWNER: 130-134 Holdings LLC

ARCHITECT: SHoP Architects

ENGINEER: Arup and Icor Consulting

Engineers

Source: ArupSource: LEVER Architecture

Framework,

Portland, OR

130-134

Holdings, NYC-134

Holdings, NYC

Overview





Ripples Builds into Swells

Designers Contractors

Government Industry

Based on research done by Perkins+Will studying several of the European Tall Wood projects, it was found that there were some common motivators for owners and designers for these projects.

Tall Wood Motivators

• Market Leadership

• Carbon Reduction

• Energy Performance

Primary Motivators

• Structural Performance

• Light weight

• Speed of Construction

• Aesthetic

Secondary

Motivators

Sky - Believe in Better BuildingOwner: British Sky Broadcasting Group

Architect: Arup Associates

Structural: Arup Associates

Contractor: Mace

Structural Frame Supply: B&K Structures

CLT Supply: Binderholz

Source: Simon Kennedy

• 1st UK multi-storey timber commercial office• 43,000 sq ft• Glulam frame; CLT slabs & shear walls• Timber cassette façade panels (passivhaus)

Sky - Believe in Better Building

BSkyB:3 months Design11 months ConstructionCLT Slabs install: 5300 – 8600 sq ft/week

ScheduleTraditional Approach:7 months Design21 months ConstructionRC Slab install:3200 – 4300 sq ft/week

Comparison of Traditional approach Vs

BIBB.

• Glulam Frame starts 3 March and will

complete in 7 weeks.

• Timber cassette cladding will follow two

weeks behind frame, completing in 7

weeks.

• Building will be 70% weather-tight in 8

weeks – temporary membrane attached to

north elevation to allow fit-out to start in

parallel with Glazing

• Fit-out double-shifts.


Government Industry

The US is 100 million acres, of which 33 million acres is forested.

Dispelling Myths about Wood ProductsUS Forest Lands

PA Forest Land

Source: http://awc.org/publicpolicy/statefactsheets

U.S. Forest Land

Forest Area in the United States

1630-2007

1045

759 760 756 761 744 738 747 749 751

0

200

400

600

800

1000

1200

1630 1907 1938 1953 1963 1977 1987 1997 2002 2007

Tho

usa

nd

Acr

es

Source: USDA-Forest Service, General Technical Report WO-78. (2009).

103.7 128.3 163 190 214.3 217.6

148.5174.1

223.4244.6

256.4 268

363.7363.2

346.7347

365.1 370.5

0

100

200

300

400

500

600

700

800

900

1953 1963 1977 1987 1997 2002

Inve

nto

ry (b

illio

n cu

bic

fee

t)

U.S. Timber Volume on Timber Land

North South West

U.S. Forest Land

Source: USDA-Forest Service, US Forest Resource Facts and Historical Trends FS-801. (2004).

At least 6-7 million acres of productive forestland are in need of forest health and/or fuels reduction treatments.

Western U.S. Wild Fire Epidemic

• Fire readiness and

suppression has

gone from 20% of

the FS budget in

2001 to 52% in

2015.

• It is not uncommon

to spend $1 million

per hour fighting

fires.

Source: US Forest Service –http://www.fs.fed.us/about-agency/budget-performance/cost-fire-operations

Insect and Disease Risk Map

Inter-Mountain West Insect Devastation

Source: IDS- Insect and Disease Survey USDA Forest Health Protection

U.S Contribution to World Emissions

Dramatic Potential for Change

100% 41%

Standard Materials

Source: Timber Tower Research Project, Skidmore, Owings and Merrill, May 2013

Timber Hybrid Prototype

Reinforced Concrete Benchmark

58

Rural Economy Benefits

PA State Economic Impact

Source: http://awc.org/publicpolicy/statefactsheets


Government Industry

Overview





– Acoustics

– Structure

– Fire

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



Source: Graphic provided by ARUP, CLT data provided by FPInnovations

Structural Design

CLT Gymnasium

67

Code Compliance Pathway

EQUIVALENCY

Authoritative Documents – eg. ASCE 41-13

ASCE 7-10

ASCE 7-10

Structural Testing – Lateral Systems

Cross-Laminated Timber Post-Tensioned Rocking Shear Walls

Structural Testing – Lateral Systems

Cross-Laminated Timber Post-Tensioned Rocking Shear

Walls

Structural Testing – Lateral Systems,NSF Testing

Source: S. PEI et al.

Structural Testing – Lateral Systems,NSF Testing

Heavy Timber Buckling-Restrained Brace

© Arup North America Ltd. Distribution and Reproduction By Permission Only

HTBRB Specimen Exploded View

CNC Wood Fabrication

HTBRB Specimen Cross Section

Fully Threaded Screws

Heavy Timber Buckling-Restrained Brace

76

Building Height Limits in Timber

International Code Allowances

So what can you achieve in terms of heights for Type III and Type V buildings? This table summaries the possibilities using our more typical occupancies and starting with allowances in Table 503 and expanding those to what is allowed with an NFPA 13 sprinkler system.

Building Heights and Stories by Building Type

With NFPA 13 Sprinklers

Occupancy

IIIA IV VA

85 ft 85 ft 70 ft

R-1/R-2/R-4 5 5 4

A-2/A-3 4 4 3

B 6 6 4

M 5 5 4

S-2 5 6 5

S-1 4 5 4

Summary of IBC Maximum Heights

**ASCE7 12.2-1 limits wood shear wall seismic systems to 65’ in height in SDC D,E,F

Expanding Stories with Podium

IBC Provisions for Mixed-Use podium have been evolving.

IBC 2006 2009 2012 2015

Section 509.2 509.2 510.2

Upper

Occupancy

A, B, M, R or S

Lower

Occupancy

S-2

Parking

A, B, M, R or S-2

Parking

Any

Except H

Podium

Height

1 Story Multi-

Story

2015 IBC will allow multiple podium stories above grade.

AWC conducted a very successful ASTM E119 fire endurance test on CLT wall at NGC Testing Services in Buffalo, NY to substantiate the inclusion of CLT in the building code and include it for 2-hour fire resistive rated assembly. The test was successful for 3 hours and 6 minutes, far outlasting the 2-hour goal. Chapter 16 of the National Design Specification NDS also provides fire design calculations (char rate) for exposed wood members requiring up to a 2-hour rating.

Fire Test Results

ASTM E119 Fire Endurance Test

• 5-Ply CLT (6-7/8” thick)

• 5/8” Type X GWB each side

• 2 hour target

• Actual 3 hours 6 minutes

2015 NDS Chapter 16

includes char rates for

CLT to achieve up to 2

hour fire rating

Approved fire rated assemblies are an important role in selecting

building framing and finishing systems. It is increasingly difficult to find tested fire assemblies that meet the building’s needs from other perspectives, such as acoustics, energy compliance, building envelope, special structural needs and even aesthetics.

The easiest way to prove an assembly is properly rated for the application is to use a tested assembly however, it is more common in mid-rise construction that you will need to use all of these methods and it is helpful to know how others are doing this.

The three basic ways to establish a fire rated assembly is by 1. Tested the assembly to E119 standard. Most think of UL but there

are other sources of assemblies. AWC and APA both have information on tested assemblies

2. Deemed to comply tables and3. Calculated fire resistanceAn advantage to DCA 3 is that you can use 100% of the design load where a reduced loading is required in the deemed to comply tables and other approved assemblies.

Exposing StructureIBC 703.3 Alternate Methods for determining fire resistance

• Prescriptive designs per IBC 721.1

• Calculations in accordance with IBC 722

• Fire-resistance designs documented in sources

• Engineering analysis based on a comparison

• Alternate protection methods as allowed by 104.11

IBC 722 Calculated Fire Resistance

“…The calculated fire resistance of exposed wood members and wood decking shall be permitted in accordance with Chapter 16 of ANSI/AF&PA National Design Specification for Wood Construction (NDS).”

NDS Chapter 16 Fire Design of Wood Members

Limited to calculating fire resistance up to 2 hours.

Char rate varies based on endurance required, product type and lamination thickness. Equations and tables provided.

TR10 and NDS commentary are helpful in implementing permitted calculations.

Distinctions between Type III and Type V wood-framed mid-rise buildings go beyond the allowable heights and areas. In addition to the use of FRT, a big difference between Type III and V is the fire-rating requirement at the exterior bearing wall. Table 601 requires that both Type IIIA and IIIB structures have two hours of fire protection on the inside face of the exterior wall lines.

This jump in fire resistance both for the exterior wall and the firewall is not as straightforward as simply finding a UL assembly with an increased rating.

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 Testing – Wood Char

Fire Performance

Co

mb

ust

ibil

ity

Fire Resistance

Flame SpreadClassification

And Then the Wave

SEATTLE PORTLAND VANCOUVER PORTLAND

PORTLAND PORTLAND PORTLAND MINNEAPOLIS

6 Stories/85 ft 5 Stories 3 Stories/63 ft 5 Stories

5 Stories 6 Stories/ 85 ft 4 Stories 7 Stories/ 85 ft

Contact Information

Hans-Erik Blomgren

[email protected]

206-493-2248

Lisa Podesto

[email protected]

530-520-7966

mailto:[email protected]

mailto:[email protected]

Summary

• Reviewed the historical context for tall timber structures, and considered the construction and sustainability motivators driving modern examples.

• Learned how tall timber can achieve design goals outside of code requirements including high acoustical performance, unique aesthetics and ambitious sustainable objectives.

• Discovered how tall timber can achieve structural performance and approval in the US.

• Realized how tall timber can achieve fire performance and approval in the US.

Presentations & Public Speaking

AIA 2016 - The Momentum of Tall Wood Buildings