Architectural
CLT
Discourse + Prototyping + Implication Within the Built Environment
Abstract The State of Mass Timber Mass
timber,
specifically
Cross
Laminated
Timber (CLT) is one of the largest paradigm shifts seen to building structural systems since the industrial revolution and yet it has rarely surfaced as a topic of architectural discourse. By nature of how mass timber is produced, via downstream digital fabrication outputs, its best architectural treatment is explicitly tied to an understanding of how the material is manufactured in the first place. Effective design with timber is not just choosing from a kit of parts, but levering a knowledge of CNC fabrication to produce structural members and thoughtful joint details that support architectural intent. Therefore, this thesis deliberately explores the role of manufacturing plant within timber production,
and
how
architecture
interfaces with heavy industry.
Figure 1
directly
Emphasis is
placed on the role of the factory as a center for outputting mass timber components, while analyzing and critiquing current manufacturing and fabrication practices.
As the node for
timber output the factory is the intersection at which architecture and industry meet, and the ideal congruence to showcase mass timber design against its hyper efficient manufacturing environment.
Architectural
CLT
Figure 2
Section Head
3
Vertical Integration A Cohesive Manufacturing System As architects, we are left to confront the
but leveraging a body of knowledge on CNC
technology to decrease fabrication time, cost,
question, how does our industry interface
manufacturing to produce building elements
waste generation, all for the relentless pursuit
with manufacturing and fabrication to output
that support architectural intent. What follows
of increased quality within a product39. Mass
streamlined building components? Equally as
is a graphical analysis of parallels in downstream
timber stands as one of the few AEC practices
important, what material(s) exists that allows for
manufacturing,
timber’s
to date that has kept pace with the optimization,
such an integrated, vertical production model?
delivery mechanism against other industries
quality control, and mass customization these
Interface is important to note as distinct from
such as automotive and aviation.
other product assembly industries, enabling
comparing
mass
wood design to graduate from site construction
interact, collaborate, or specify. Mass timber, therefore, is a prime material candidate for such
The argument of uniting material sourcing,
an investigation. CLT’s best architectural uses
to
are explicitly tied to an understanding of its
assembly is not a new one. With the exception
Against this backdrop, the current status of mass
manufacturing process. As such, its components
of construction, every other manufacturing
timber output is examined and analyzed, with
are not simply just choosing from a kit of parts,
driven industry has successfully leveraged high
an effort to critically suggest a more seamless
Figure 3
Architectural
CLT
design,
through
fabrication,
and
to prefabricated mass customization41.
final
mode of operation.
It should be understood
in house, to a timber manufacturer’s exact
understanding of how the material is produced
specifications for laminating.
in the first place.
to advance and streamline its already efficient
This supply chain consolidation is within the
Again,
nature.
same spirit as braiding the architect or designer
suggestions, going against the grain of current
more closely to the manufacturing process.
market practices. Any change to an established
By shipping roughsawn lumber directly to the
Mass timber is highly unique in its manufacturing,
manufacturing
factory for drying and planing, a key element of
where neither the input (i.e. billet size) nor the
incremental. Improving the efficiencies of mass
redundancy in the cycle is eliminated, as each
output (what is actually machined) is fixed. An
timber will only further rapid expansion within
lamella only has to be planed to final dimension
integrated model of delivery allows a designer
the AEC industries.
once. Furthermore, a manufacturing facility’s
to capitalize on these nuances without driving
proximity to sawmills becomes less essential,
the cost up for custom componentry. In turn,
as final dimension planing can be accomplished
it requires that a designer have an intimate
that critiquing this delivery system as a forest to building commodity is a speculative attempt
these
critiques
system
will
are
speculative
necessarily
Vertical Integration
be
5
Figure 4
Figure 5
Architectural
CLT
Vertical Integration
7
Figure 6
Figure 7 Architectural
CLT
Section Head
9
Speculation Timber & The Midwest It is precisely this discussion of a cohesive delivery system that necessitates so much emphasis be placed on the manufacturing plant itself. It is no secret that there is a direct correlation between the location of a CLT manufacturing facility, and the likelihood that a given construction project will be manufactured out of mass timber. One of the largest reasons we have not seen any significant mass timber structures appear in such densely populated places as Chicago and New York, is frankly the fact that Midwest and East Coast of the US is are a CLT desert. A Midwestern manufacturing node today seems speculative at best. However, as North American timber usage continues to expand eastward, future sites for expansion will necessitate looking to locations that balance proximity to resource with proximity to population densities. With cities like Portland, ME consider the impact of timber manufacturing on their economy17, Midwestern sites like Cincinnati become more logical choices for CLT delivery in a network system of production. Bridging the gap between the active manufacturing plants of the Pacific Northwest and forest reserves of the east is the ultimate necessity to realize mass timber as a widely used building commodity across North America.
Architectural
CLT
Figure 8
Speculation Cincinnati As A Hub 1 - Centralized location between existing Southern Yellow Pine and Spruce Fir existing forest reserves. 2 - Centralized location between several urban population centers, including Chicago and Washington DC. 3 - Low cost of land throughout the city, especially in old industrialized areas. 4 - Convergence of Interstates 71, 75, and 74 for rapid CLT panel distribution via truck. 5 - Largest Midwest rail yard after Chicago, offering a robust secondary means of panel transit beyond trucking. 6 - Ohio & Indiana’s abundance of farmland and the potential for locally farmed generation 2 forest reserves. 7 - The Midwest’s suitable climate for alternate mass timber tree species such as Jack Pine. 8 - Urban siting of a manufacturing facility brings exposure and education to an AEC industry not trained in the detailing and construction of mass timber.
Figure 9
Speculation
11
Conclusion Timber and the AEC Industry It is time the use of mass timber be considered as a forest to building commodity, a turn key material architects interface with.
This
proposition is inherently multi faceted, spanning from economic, construction, manufacturing, and design practices.
If the emerging North
American market of mass timber is to rapidly expand, its use must stem from an infrastructure of delivery.
Such a system allows for widely
customized use of the material, even at mid rise scales. Architects must align themselves with the embedded processes of manufacturing and fabricating such a material, in order to fully leverage its capabilities.
When CLT is
approached with a vertical model of production, both
architects,
engineers,
manufacturers,
fabricators, and contractors can all act in unison to transform the material into an efficient, highly tolerance, elegant structural product that mirrors the production model of almost every other industry outside of the AEC circle. There in lies the real substance downstream digital manufacturing brings to buildings and construction.
That is the true paradigm shift
mass timber has the potential to bring to the architecture.
Figure 10
Architectural
CLT
Captions & Notes 1.
Sectional study of manufacturing facility, lamella truss enclosure
2.
Scale study, human against machine
3.
Mass timber supply chain, current state of operation
4. Tesla integrated manufacturing and delivery model 5.
Boeing, vertically integrated jet production, in partnership with Rolls Royce
6.
Ideal mass timber supply chain; timber as a forest to building commodity
7.
CNC etching study, mode of representation looking at the architecture of a Midwest timber factory
8.
North American forest reserves; major species specific to mass timber manufacturing
9.
Site studies identifying potential land locations for a timber manufacturing hub, Cincinnati, OH.
10. Study of support infrastructure, both interstate and rail, Cincinnati OH. Site selection was based primarily on the ability to easily move material in and out via truck or rail. Reference numbers below are matched to correspond with thesis document footnotes 17. Assessing the Wood Supply and Investment Potential for a New England Engineered Wood Products Mill New England Forestry Foundation 39. Refabricating Architecture - Stephen Kieran, James Timberlake 41. Next Generation CLT, Mass Customization of Hybrid Custom Panels - Todd Beyreuther