Grantee Research Project Results

Final Report: 3D Printing Sustainable Building Components for Façades and as Window Elements

EPA Grant Number: SU835547
Title: 3D Printing Sustainable Building Components for Façades and as Window Elements
Investigators: San Fratello, Virginia , Speer, Leslie , Straubing, Cassandra , Wright, Shannon , Binni, Anyssa , Everling, Marissa , Wagner, Molly , Leroux, Victoria , Molkenbuhr, Deanna , Velazquez, Angelica , Murri, Stephanie , Shirazi, Shaharyar , Scarpello, Biaggio , Bowles, Carolyn
Institution: San Jose State University
EPA Project Officer: Hahn, Intaek
Phase: II
Project Period: August 15, 2013 through August 14, 2015
Project Amount: $89,940
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2013) Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Sustainable and Healthy Communities , P3 Challenge Area - Chemical Safety , P3 Awards , Sustainable and Healthy Communities

Objective:

The project is an integrative educational and research project that will revolutionize design and construction methods towards more sustainable buildings. The project goals included developing and testing new materials for additive manufacturing and the development of new product design concepts as window elements in the architectural design of buildings. The 3D materials we printed with include pulverized wood flour in a 3D printer – a material made of recycled and agricultural by products, wood filament on a fused deposition modeler and paper on a Laminated Object Manufacturer. These alternative construction materials and their respective building components resulted in new curtain wall products that are derived from biodegradable, renewable and recyclable resources. The challenge was to develop alternative and innovative design concepts and products that optimize on the unique properties               of these materials and the process of 3D printing.

The façade elements that were designed were targeted at the construction industry and have been and continue to be evaluated in the context of economy, manufacturing, energy conservation, thermal performance, structural strength, durability, construction assembly, end use and disposal. The project integrated the disciplines of art, architecture, interior design, environmental technology, materials science, industrial engineering and natural resources.

The design concepts were evaluated through professional practice peer review, materials and manufacturing analysis, prototyping, laboratory testing, computational simulation and life cycle analysis. The positive implications for P3 have been to encourage the use of a fabrication method that minimizes waste and engages in environmentally conscious manufacturing and uses only recycled or recyclable materials, serving to preserve the planet’s natural resources. The pedagogical value of this project has been translated to students through the different disciplines into a number of architecture, design and art technology courses in each of the associated departments.

Purpose:

To develop curtain wall and free standing structural wall systems using additive manufacturing technologies and wood-based materials.

Objective:

To design, fabricate and evaluate three prototypical wall/ curtain systems using formulas that include:

1. 3D Printed wall using wood flour formula in the Z CORP 3D printer.
2. 3D Printed curtain using Wood filament in the Fused Deposition Modeler (FDM)
3. 3D printed curtain using recycled content paper in the MCOR printer.

The three wall systems (2 as window and façade elements or curtain walls and 1 as load bearing wall) will be installed in a public venue where mechanical, structural, chemical and optical properties of the walls will be measured over time.

Scope:

During phase I, the SJSU P3 team developed a precise recipe for 3D printing with wood flour that yields a strong and stable end product. Students in dsIT 103 and 109, an interior design studio and a product design class at SJSU, proposed designs for a series of new building products made of the wood flour. The products were designed to reduce energy use in buildings and computer simulations were modeled and analyzed using ecotect.

During phase II the SJSU P3 teams worked in three groups in order to test materials for compressive, strain and tensile strength and to design and fabricate the three respective wall systems. Each group was also responsible for developing a digital model to simulate interior lighting and thermal conditions and each group ultimately installed the walls in three different locations in the Bay Area for future evaluation.

Summary/Accomplishments (Outputs/Outcomes):

3D Printing with Wood: Sawdust Screen

The Sawdust screen is 3D printed using pulverized walnut wood flour. The formula below was developed specifically for this application and we have a 90% success rate when printing parts using this formula. The screen is designed to be freestanding and has a curved base. Various sizes openings in the screen allow for the transmission of light and views since the material itself is opaque.

The formula for 3D printing with wood powder is:

• 4 pt wood
• 1 pt resin glue
• 1 pt wheat paste
• *layer thickness: .035”
• *saturation: outer 145 / inner 145
• * note: these numbers may vary depending on ambient temperature and humidity.

Strength Testing of 3D printed wood:

• Compressive strength = Max Load 902 psi on 3” dia. By 6” tall cylindrical specimens printed on a zcorp 310 plus.
• Strain        
• Tensile strength Thickness =.112” Width = .490”
• Equipment used: M200 (Tensile testing courtesy of Kimball International
• Displacement reading: 63 lbs.
• Yield 1,148 PSI
• (as a point of reference MDF has a tensile strength of 2000 psi)

Light transmission:

1. Pine, Maple Walnut: none. Because of the minimum thickness of 1/8” associated with extracting the 3d printed wood from the build bed there appears to be no light transmission through the wood.

Fire Resistance

1.  Pine, Maple, Walnut: The 3D printed wood specimen of 1” x 2” x 1” charred but did not exhibit dripping or bubbling, the characteristics that one might find in a polymer. The specimen acted more like mdf (medium density fiberboard) or particleboard.

Water absorption characteristics

1.  Pine: The 3d printed pine does exhibit weight gain when left to soak in water therefore it does absorb some water. The material specimen weighed 2.2 ounces before the test and 3.375 ounces after the test for an increase of 53%.

FDM with PLA: Cell Veil

We have developed a 3D printed curtain using the wood filament. The wood filament has proved to be incredibly difficult to work with. There is a 75% failure rate using the material as it frequently clogs the hot end of the printer. Therefore, we do not recommend using this material for large-scale applications. Ultimately, because of the frequent failure with the wood, we reverted to using PLA to finish the curtain. PLA is a biodegradable thermoplastic, which is derived from renewable resources, such as cornstarch, sugar cane, tapioca roots or even potato starch. This makes of PLA the most environmentally friendly solution in the domain of 3D printing.

Equipment used: Makerbot Replicator 2 (Testing by MakerBot - two different print settings were evaluated:

• STD or Standard (Standard resolution, infill, shells, etc)
• Sliced on MW 2.4.1.24
• 100% Standard PLA profile setting
• Make -> Select Material -> Select ‘Standard’ Resolution
• MAX or High resolution, 100% infill
• Sliced onMW2.4.1.24
• ‘High’ PLA with 100% infill
• Make -> Select Material -> Select ‘High’ Resolution
• Infill to 100%
• For PLA, samples were prepared using a Replicator 2
• Compressive Strength standard = Max Load 2600 psi
• Compressive Strength high = Max Load 13600 psi
• Tensile Strength standard = 6783 psi
• Tensile Strength high = 9531 psi
• Flexural Strength standard = 8970 psi
• Flexural Strength high = 13731 psi

Findings:

All of these materials are strong enough to be used as self-supporting interior walls, screens, partitions and curtains.

ior applications these material will need to meet flame propagation performance criteria of NFPA 701 or be noncombustible. Testing by Macgill Services is being undertaken to ascertain whether these material meets the requirements of the International Building Code. Data will be available in early 2016.

Because of the water absorption characteristics in all of these materials we do not believe they are suitable for exterior applications only interior applications that do not have excessive humidity.

LOM with Paper: Wall Paper

We have developed multiple designs for both 3D printed curtains and 3D printed walls using the recycled paper and have printed small prototypes of each design as a way of testing the potential for printing modular units. Thus far the Mcor printer has a success rate of 86% when prints are less than 2” high. When prints exceed 2” the success rate reduces dramatically primarily because of paper feed errors and nonrecoverable controller errors. Of 40 test prints approximately 22 have printed successfully and 19 of those were less than 2” high. Of the remaining test prints that exceeded 2” only 3 have finished printing for a success rate of 16%.

Strength Testing of 3D printed paper:

Equipment used:(Testing courtesy of Dr. Fritz Yarborough, Professor SJSU) two different orientations were evaluated:

• horizontal lamination and vertical lamination
• Sliced on SLICEit
• 100% Standard profile settings

a.       Compressive strength horizontal = Max Load 25,421 psi on 3” x 6” dia. tall cylindrical specimens printed on a Mcor Iris.

b.       Compressive strength vertical = Max Load 1967 psi on 3” x 6” dia tall cylindrical specimens printed on a Mcor Iris.

Light transmission: The laminated paper parts do not transmit light.

Fire Resistance: The laminated paper specimen of 1” x 2” x 1” chars and burns as expected.

Water absorption characteristics: When wetted, the laminated paper rapidly absorbs water, swells and delaminates.

Environmental Data

The design of the mass customized façade elements result in passive heating and cooling, which would decrease energy consumption and expenses to the building. The window façade elements decrease the building’s interior heat gain. The monetary, environmental, and health impacts affected by the regulation of building temperatures is cause for great concern. The window façade systems would reduce the need for expensive and wasteful heating and cooling systems and provides for healthier, natural environments for people.

Approach:

Students developed over 20 different design proposals that use the 3d printed materials as window and façade elements. The various design proposals have researched applied methods of generating geomemetic strategies for the design of window elements that respond the solar conditions and adjacent programmatic conditions.

A simulation of a 6’ x 10’ window that faces south on a building in Los Angeles, CA . The window sits 18” above the finished floor and the wall surrounding the window is made of concrete masonry units. Outside the window is a pedestrian walkway and the person sitting and working in the interior needs to have views of the exterior walkway but limit the views from the exterior to the interior to ensure some privacy when the person is working at his / her desk. There are no trees or buildings in front of the window and in the summer the interior experiences considerable heat gain but in the winter it gets cold because the glass opening is so large therefore we have developed designs that block the high summer sun but allow the low winter sun to enter the interior. The person working behind the window sits at a desk and uses a computer and needs to minimize the amount of light and glare on his/ her work surface and monitor. A person needs about 30-50 foot-candles of light at the desk surface to work comfortably. Adjacent to the desk is a sitting area where the person meets with clients, sits to each lunch and sometimes to rest or brainstorm. In this area privacy is not an issue nor is glare, only heat gain and loss. The room is 10’ x 10’ x 9’.

Students designed multiple 3d printed curtains (or window elements) that mediate light, views and temperature. All of the curtains exhibit variation across the surface as the geometry measures and maps the necessary and real time functions that must take place across the surface.

Each student began by generating a gradient map that illustrates the amount of light/view one will need to achieve across the surface. Dark colors will represent the least amount of light and light colors will represent the most amount of light.

Secondly, each student modeled a simple cell that was 3D printable and could transform across a surface. Students experimented with replicating the cell on a variable surface using the following techniques:

1. Use the array too to generate a surface from the cell.
2. Use the falloff tools to generate strategic variation across a regular surface.
3. Model a cell and use the clone tool, experiment with changing scale, rotation, jitter, etc. to achieve meaningful variability across the surface.
4. Model a cell and manually generate the surface through replication
5. Use paneling tools in Rhino to generate a unique surface.

The resultant designs have been tested against summer and winter solstice conditions to and measured using Ecotect software to determine resultant heat gain and loss and comfort levels provided by their designs.

3D Printing with Wood: Sawdust Screen 

Winter Solstice 11:10 am Summer Solstice 11:10 am photo of 3D wood print

Findings: The new mass customized 3d printed wood window elements permit winter sun but block summer sun yet still permits views and natural light to enter the interior. They also allow for more light is the seating area of the room and less light on the surface of the desk where one might need lower light levels and reduced glare.

Ecotect Charts that show outside temp. and inside temp. with no window treatment:

Winter Interior zone temp during workday: Summer Interior zone temp. during work day:

Degrees: 50-53 F – too cold                             Degrees: 75-86 F – too hot

Ecotect Charts that demonstrate inside temperature with mass customized 3D printed wood window elements:

Winter Interior zone temp. during workday:            Summer Interior zone temp. during work day:

Degrees: 57-68 F                                                          Degrees: 68-76 F

Findings: We have developed a workflow and technique for designing mass customized window elements effectively keep the interior space 7 to 15 degrees warmer in winter and 7 to 10 degrees cooler in summer.

Outputs:

1. Developed formula for successful 3D printing with wood flour.
2. Pedagogical workflow that demonstrates how mass customized window elements can be designed to positively affect the interior climate of a building.
3. Design and fabrication of 3D printed wood prototype, the Sawdust Screen, at full scale installed in Oakland for empirical testing.
4. Design and fabrication of FDM bio plastic curtain, the Cell Veil, installed in San Jose for empirical testing.
5. Design and fabrication of LOM paper curtain, the Wall Paper Curtain, installed in San Jose for empirical testing.
6. The Sawdust Screen was displayed at The Cooper Hewitt Smithsonian Museum as part of the “Beautiful Users” exhibit in 2015 and will be on display at the at the Museum of Design Atlanta in 2016.

The final 3 designs, the Sawdust Screen, the Cell Veil and the Wall Paper Curtain are the result of many long iterative design sessions, small parts were fabricated and analyzed both qualitatively and quantitatively and redesigned prior to fabrication of the final piece so that we might meet the requirements set forth by our goals. As is often the case in design there is not one correct solution but rather many possible solutions. Therefore more important that the final products itself is the understanding of the materials physical and material properties and limitations, the development of a design methodology that can be repeated successfully and a strong knowledge of the best practices when using the equipment. Establishing a methodology for working with these novel materials and the 3D printers themselves and the development of pedagogical handbook of best practices for the design and simulation of the mass customized geomemetic screens and curtains has been the most valuable outcome of the research.

Outcomes:

1. Extensive educational opportunities for developing new 3D printable materials have presented themselves. Since developing the wood subsequent faculty and       student teams have gone on to independently develop formulas for 3D printing with other materials including rubber (from recycled tires), coffee flour and rice husks using the equipment purchased with the grant.
2. Multiple partnerships, the most pertinent of which are the relationship with Ronald Rael, Director of the “printfarm” at the University of California and Luisa Caldas at Lawrence Berkeley Labs who specializes in the development of computational tools and workflows to integrate sustainability in complex architectural concepts. They have both provided us with support including assistance with the printers and in evaluating our designs.
3. The development of an evolutionary computation and generative design system and workflow for producing sustainable façade elements.

Conclusions:

In conclusion, one of the strengths of this research has been in the development of new sustainable materials for 3D printing. The materials that we have been developing are in the waste stream and are inexpensive or free in many cases. Developing new materials out of recycled and waste products reduces costs associated with 3D printing by over 90% and makes this technology more accessible to more people and benefits the planet.

• 30 lbs. of 3D systems proprietary powder = $1090.00 30 lbs. of our wood powder mixture = $50.00.
• 1 gallon of 3D systems proprietary binder = $633.00
• 1 gallon of our rice alcohol binder = $32.00

Another valuable outcome that we will continue to deploy and refine in subsequent courses taught at SJSU is the development of an evolutionary computation and generative design system and workflow for producing sustainable façade elements. The workflow however falls short right at the point of analysis. We are able to simulate complex geometries in the computer but have not been able to evaluate such complex and custom designs successfully. Unfortunately, the software on the market is only useful  for simple designs that are more binary and less complex. This is what led us to seek out Luisa Caldas at Lawrence Berkeley Labs who is developing software applications that use shape grammar to inform energy efficiency.

Finally, the acquisition of the equipment and the time needed to become proficient in using the equipment combined with the time required to design and fabricate the façade elements means that we have only just completed and installed the final prototypes. Further empirical evaluation of the screens will need to be completed post grant.

Journal Articles:

No journal articles submitted with this report: View all 3 publications for this project

Supplemental Keywords:

3D printing, wood, glass, additive manufacturing, passive solar design, reduced energy consumption, ecotect

Relevant Websites:

3D Printing with Sustainable Materials JSU Exit

Progress and Final Reports:

Original Abstract

2014 Progress Report

P3 Phase I:

3D Printing Sustainable Building Components for Facades and as Window Elements  | Final Report