Over the last number of decades, the amount of furniture in landfills has increased dramatically along with the demand for fast furniture. While inexpensive and quick to produce, these cardboard and plywood furniture pieces often contain toxic chemicals and only last a short time before being thrown away and replaced. Growing furniture from mushrooms benefits the environment by absorbing carbon-dioxide during production, and reduces the need for furniture disposal once the product reaches end-of-life.
Mycelium is the main body of fungus, that when grown together with crop waste forms a water resistant, flame retardant, and fully biodegradable Styrofoam-like solid. Mycelium furniture is grown from this composite into simple modular shapes. Once grown, the pieces are attached using bamboo components. The modules can be disconnected and rearranged to form stools, benches, and chairs, adapting to fit environmentally-conscious furniture into different types of indoor spaces.
Slide by Slide Presentation Transcript
Hi, I’m Myles, and for my capstone I worked on creating mycelium furniture and I also designed modular mycelium furniture for possible production.
I’m going to begin by talking a little bit about the topics connected to the project as well as how they connect to each other, mainly sustainability, furniture, and the connection being the environmental effects of the fast furniture industry.
I began this project with my interest in bioplastics, which are plastics derived from biological materials as opposed to petroleum, and I started learning about them and other sustainable materials in my sophomore year Materials Lab D-block where we explored and created our own bioplastics.
I wanted to create furniture and I decided to do it in a mid-century/Scandinavian minimalist style, which is the style that I’ve been influenced and inspired by. So when I began the project, I set out to design mid-century modern furniture that incorporates bioplastic and CNC milling, CNC milling being basically a computer-controlled drill bit that can carve and cut materials, and I wanted to learn how to use that as well as create interesting furniture designs with it.
Some background on mid-century modern design, these are a few notable examples, but it’s generally characterized by clean lines and a lot of attention to detail with warm inviting curvature.
Sustainability is “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.”
Historically, this has meant finding a balance between the consumption and regeneration of resources, so if you were going to make paper you would make sure that you don’t cut down more trees than could grow back, but now this expanded more to being conscious of the environmentally detrimental effects of the resources we use and the byproducts we create. This means making sure that we understand the effects on the local ecosystems between the time we remove a resource from the environment and when it regenerates. It also means making sure we don’t release toxins back into the environment from the processes we use in production.
You might know fast furniture as something like IKEA stuff. It’s generally inexpensive and made of cheaper materials like plywood, particleboard, and cardboard, and it’s much lighter than traditional solid wood furniture, so it could be considered to use fewer resources, yet the binding agents used to glue these composites together often contain formaldehyde, which is a known carcinogen and general toxin, and instead of lasting generations like traditional wood furniture, fast furniture needs to be replaced in months or years, so a lot more ends up in landfill.
Over the last number of decades, furniture production and the amount of furniture in landfill has increased dramatically. Between 1960 and 2017, annual furniture production in the US increased by over 450%, which is 10 million tons, and although we’re recycling more there’s so much more being produced that the amount of furniture in landfill increased over 350% in the same time period.
I wanted to look at ways to help improve this process, so I began looking at what kinds of materials we can use to create more sustainable furniture, and also how to create environmentally conscious furniture to be more accessible, since it’s currently difficult to find and also very expensive.
After researching bioplastics over the summer, I realized I didn’t have the resources to work with them at a large scale, so I shifted to using mycelium instead. Based on the properties of mycelium, I decided it would be best to go with minimalism and clean lines and drop the detail and curvature of mid-century furniture because mycelium can crumble fairly easily.
I’ve mentioned mycelium a few times, but I haven’t really explained what it is. Mycelium is the massive hyphae of a fungi, or the body of a fungus. It’s not the flowering body, which would be the mushroom. It’s the part that grows underground and holds the ground together.
To use it as a material, it can be mixed with crop waste, in my case hemp hurds, and the fungal cells bind to cellulose structure, which would be the crop waste, to form a stronger material that can be grown in molds, sculpted, carved, and compressed.
The methods for working with mycelium as a material were invented by Philip Ross of MycoWorks Inc. and they also own the process patent which was filed in 2011 and granted in 2016, so this is a very recent development and new material to be working with.
The process that I go through when working with mycelium isn’t the entire thing, where you would get the mushrooms themselves and cultivate them and add in the cellulose. In my case, I order mycelium in a dry loose form, so it comes looking like mulch, which is the hemp herds, and then there’s bits of mushroom in it.
I rehydrate it, adding water and flour to start the growth process, and then that sits for four to five days until it gets a white foamy outer layer.
Then that gets crumbled up, I add a little bit more flour, and it can go into molds where it grows for another four to five days, after which it can be removed and dried immediately, or it can be incubated, so removing it from the mold and putting it in a sealed environment for two to four days in order to form a white outer layer.
Then it’s dried for two days to two weeks, and then gets baked at a low temperature for a short time just to stop the mycelium from being able to grow again if it were to get wet.
The benefits to using mycelium materials are that the growth process itself absorbs carbon dioxide, and if you make products out of it, they are fully compostable, so instead of requiring disposal at end-of-life, they can just be crumbled up and put in a garden. Using mycelium for furniture can help reduce our reliance on plastics, metal, and irresponsibly source lumber.
These are just a few pictures of different types of mycelium bricks. Mycelium itself is just the fungus, whereas mycelium as a material would be a composite, and different companies have different formulations with trademarked terms like MycoComposite and MycoFoam. The different formulations have different properties, but it’s a very similar process for working with all of them.
Some of the main resources I’ve been using throughout this project are Ecovative Design and their DIY subsidiary GROW.bio. Ecovative Design produces mushroom packaging, so instead of having foam corners in the packaging for a large heavy item that gets shipped to you, they might be made out of mycelium instead. Ecovative Design also produces videos and writeups on working with mycelium, and they partner with companies around the world to provide resources and materials for working with mycelium outside of the US.
GROW.bio is where I purchased my mycelium. They also produce videos and instructions, and have a shop that has all the tools and resources to work with mycelium at home.
Since mycelium is a new material to be working with, there’s been a lot of experimentation, including in furniture. One notable example is mycelium chair on the left, which is printed on a 3d printer using PLA which is a bioplastic. It is then filled with mycelium since it has a hollow form and allowed to grow. The mycelium is not killed off, so mushrooms end up growing out through the chair and it becomes more of a living art piece.
On the right is more of a traditional way of working with mycelium similar to what I did at home. This stacked stool is made in thinner sections that are grown in a mold and then removed and grown together to form a larger object. This process allows you to create things at home using a simple mold that only has ventilation on the top, where you wouldn’t want to go more than four inches thick because air does need to circulate throughout the mycelium, which is what I did at home, but for the projects that I designed for manufacturing, they would have ventilation on all sides. A massive part would require tubing and air pumps to make sure air gets through so the material grows evenly.
There has also been some experimentation with mycelium material in architecture. The Growing Pavilion on the left was on display at Dutch Design Week 2019, and it’s a large outside structure with mycelium as the outer walls and also the seating that looks like plywood is compressed mycelium, so it’s a lot stronger. It’s a really interesting building where they grow cattails, the material that the floors are made of, inside the building, so they grow that materials to make the building inside the building.
Now on the right is MycoTree, which is an experiment in using mycelium as a structural component in architecture. It’s grown in small parts that are then attached to each other and the intention is for it to be able to transfer weight and hold up a ceiling.
Towards the beginning of the year, I began experimenting with mycelium on my own.
I started designing a side table that was going to have a cutoff conical shape to it. I started by creating a mold template…
and then making cardboard molds. I decided to go with the teardrop shape that formed when I taped the cardboard together because I thought it was a little more interesting than the circlular base that I was going to originally use.
Although the cardboard is wrapped in tape, which is plastic and not great for the environment, this is really just a proof of concept, and in production you would be using reusable molds.
Once I had the molds, I could fill them with mycelium. I went through this entire process twice, and the first time I didn’t have enough mycelium to work with so I had to rush and figure out how to create some spacers, and ended up needing to use paper towels and plastic wrap, although the second time around I used cups which would be reusable for other times that I do it. I didn’t fill all of the molds, so the project went from being a side table to being more of a coffee table height.
After letting the pieces grow in the molds, I removed them and stacked them, and then they grew again.
On the left is the final result of the first attempt that I did, where I ended up sanding down the mycelium to make a smoother finish, and the intention would be to paint this with milk paint, which is protein-based as opposed to the polymer, or plastic, of a traditional paint.
The second time around I let it incubate for a little bit longer to form more of an outer layer and I left it with a natural finish.
The difference between the finishes is that with the white outer layer it has a bit of a velvety texture to it in the end, whereas leaving it without the white layer it is still fairly smooth where the mycelium grew against a smooth mold, but it feels more like pressed wood, where there’s definitely a difference where the pieces grew together.
Sitting on the mycelium is fairly comfortable. It doesn’t compress like foam or upholstered furniture, but it’s not cold or hard like concrete either.
This is a render of what these bases could look like with a glass table top, so they would be used as coffee tables.
Last mod I spent my time at NuVu, an innovation school in Cambridge, to work full-time on my capstone project. Due to COVID-19 I did this digitally, so although I went there with the intention to create furniture with a CNC milled bamboo structure and adding mycelium onto it, I ended up moving more to 3d modeling and rendering as opposed to creating something in the physical world.
I chose to work with bamboo because it’s a much better source for lumber than the other options available. It grows extremely quickly, up to almost a meter per day, and can adapt to different climates and soil types, so it can grow in many places around the world. Bamboo is also very strong, but the thing with working with bamboo is that because the stocks have a very small diameter, it needs to be in plywood form, so it’s essential that this is formaldehyde-free, green plywood.
When I was looking at what kinds of designs I would work with, I started thinking about what type of product I wanted to create. On the left, this mycelium chair is a very thin piece of the mycelium material which looks clean and light, but it would require an understructure of wood or metal inside the mycelium because otherwise it would just break in half were someone to sit on it.
On the right is MYCOsella, which has much thicker sections that can actually hold weight themselves and don’t require additional components, so that’s the way I decided to go.
I also looked at cork furniture to look at different shapes I could work with. Cork and mycelium have somewhat similar properties, even though cork would possibly be carved and mycelium would be grown in a mold, so they have similar possibilities for shapes, so I looked at that for some design inspiration as well, and I decided to go with modular furniture.
When thinking about attachment methods, I found a very similar project to mine at RISD, which is modular mycelium furniture painted with milk paint. They created cylinders of mycelium that slide along a wooden base, so I decided to test that out with a slight modification, as well as explore other options.
These are some sketches of my initial designs when I was looking at different ways to work with the mycelium. There are some modular designs, some solid mycelium pieces that aren’t modular, and also the idea of having a bamboo structure with the mycelium components added on, and as I said, I decided to go with modularity.
I ended up with two main types of designs with the initial iteration, the first being home furniture. There’s the cube and rectangular prism that have a wood plank that connects them, which can be removed and configured in different ways to form chairs, benches, and television consoles.
And then there’s the wood slider like the RISD design, which I modified to use half cylinders and cubes in order to create a few different configuration options.
The second type of designs are for public furniture. This allows you to have larger pieces with interesting spoke designs for larger seating that gradually comes out against a wall, or things like the hexagonal or long benches. The intention with these designs would be to have a carved wooden surround as the base, so it’s not configurable after purchase, but there are different options at purchase. And once this is installed in a public space, people can remove the individual components, move them around, use them as side tables or stools, and then put them back when they’re done.
So far all the attachment methods have been using the additional component of the bamboo plywood, but I wanted to also explore using a mycelium on its own. I started sketching out different ways to have interlocking modules, where the mycelium would be grown in ways that it can actually connect with itself.
After dividing up a rectangle with shared angles that the pieces can be configured against each other, I played around with different ways to put them together and decided to go with this idea. On the right is a sketch with dimensions of what I actually decided to go with for the interlocking modules.
After simplifying all the designs down to what I would do for the final, I have two main types of modules.
There are the simple modules, which include the cube, the half cylinder, and the triangular prism…
And then there are also interlocking modules: The apostrophe and the chair, which are chair-like in shape, and then the double angle and single angle, which are more like side tables or stools.
I had all my designs, so I wanted to put them through structural analysis to test the way that the forms would hold up if there were actual forces exerted on them. Because I wasn’t making these in real life, I used simulations for the structural analysis, which means that you need to input all the properties of the material.
Mycelium isn’t a traditional building material, so it’s not available to select out of the box. So I needed to find all the properties myself. For the failure type, any kind of fracture or break means that the product fails, then density, yield strength, and compressive strength, I was able to find from GROW.bio where I purchased the mycelium. Density being the density of the material, yield strength being the amount of flex or bend before the product fractures, and compressive strength being the amount of compression that the material can take.
The Poisson ratio is the expansion perpendicular to compression, so if you were to squish the material in one direction, it would have to somehow come out in the other direction. Most materials are between 0 and 0.5 with this ratio, so I picked a number, around 0.35.
Then for the elastic modulus and tensile strength, which relate to the elasticity of the material, I based my estimates off of testing done on different types of mycelium with similar density that are cold-pressed or non-pressed, mine is not pressed, These materials have low scores because the material itself is not densely packed, so it’s more likely that the cellulose and mycelium would break off from each other and the piece will crumble rather than the entire thing stretching.
Once I had all the properties, I could put all the modules through the analysis, and luckily none of them showed high deformation or danger levels. So that was great.
The process of doing the structural analysis involves selecting the objects and adding the material, in my case the mycelium, then adding restraints, which would be the faces on the ground that can’t exactly push down through the surface.
The next step is adding forces downward for sitting or standing on something, and a sideways force for leaning on something or a chair back.
Then the program generates a report that includes displacement levels, which show the areas that are going to move the most. This can also be exaggerated to show how the product will compress.
The report can also show stress levels and danger levels, which will show if the product is likely to fail.
An example of this process is with the interlocking chair module. It has a 200lbs force down, and a 50lbs force back.
Then the displacement shows that the top of the back of the chair would move the most, and it marks the maximum total displacement of that area, which is not a very large number, so it’s not going to move much.
The stress levels are highest where the back and the base meet, but not too high, and the danger levels are slightly raised at that stressed area, but nothing that would cause the product to fail.
In the end, I have the simple modules with example configurations, which could include spoked seating, large hexagonal public seating, and long benches.
And then I also have both single and double width interlocking modules. The reason for both the single and double width is because certain modules, like the chair, can be a chair on their own, or a bench if it were double width. This also allows for extra ways of configuring the modules.
Some example configurations include a small chair using only single width modules, a larger chair using both single and double, long benches, and a bench with arms.
There are many ways to configure these, so I have only shown a couple examples.
I’ve talked a lot, and It’s been a long process, so I’m just going to summarize what I’ve done.
I began looking at incorporating bioplastic and CNC-milling in furniture, but switched from bioplastic to mycelium since I didn’t have the resources to work with bioplastic at a large scale. I decided to move from mid-century design to just a minimal aesthetic to better suit the properties of the material.
While experimenting with growing mycelium, I was able to test different surface finishes.
At NuVu, my plans for creating CNC-milled bamboo structures with grown mycelium pieces were derailed by COVID-19, so I moved from physically making objects to focusing on 3D modeling and rendering. I Then modeled and rendered modular mycelium furniture, and finally, I performed structural analysis tests.
Thank you for listening.
I want to thank Todd [Bartel], my capstone advisor, for guiding me throughout this process.
I also want to thank Ayako [Tanaka], my CSW advisor, for being there throughout my entire time here [at CSW].
Ammar [Ahmed] at NuVu, for helping me learn the software I needed for my project, discussing designs, and guiding me while I was at NuVu and away from CSW.
Paul [Clayton], for being available with connections to resources.
My family, for dealing with the mess I made in the basement while growing mycelium, and my stressed out self at the end of this process.
And then Alison [Safford] and Jenna [Wolf], because without their Materials Lab D-block, I wouldn’t have thought to do anything like this.
So, thank you.
Question and Answer Session Transcript
Q: What are the possibilities to use this on a larger scale, or is this important to produce on a larger scale?
A: There is a possibility to do this on a larger scale. It’s much harder to grow large mycelium pieces, so it would more likely be smaller parts that are attached to each other. I’m not really sure about the importance of using this on a larger scale at this point in time. It’s definitely interesting to look into, and it could become more important in the future, but until we figure out exactly how it works outdoors and using it on buildings, it doesn’t make sense to go right into using it at a large scale.
Q: Can you describe your intended project had COVID-19 not prevented the actual fabrication process?
A: My original plan was to model (in two dimensions) pieces that would be cut out of bamboo plywood on a CNC router. I was going to try to use a mid-century inspired design because that’s when more plastics became popular in furniture, and adopt that to be made with more sustainable materials. So it would be a structure that was made of bamboo plywood, with mycelium as extra components on it.
Q: Is mycelium’s use restricted by environmental considerations given needs for ventilation, etc.? For example, high humidity equatorial.
A: The mycelium itself can do well in humid environments because it actually creates its own, but yes, there are some environmental considerations. It gets killed off at a fairly low temperature, so it would have to be an indoor situation, and not in the sun. It also can’t be exposed to direct sunlight since mycelium would normally be growing underground and not be exposed to that. So there are environmental restrictions.
Q: Where would you like to go with this? Do you think you’ll further study this?
A: I’m not sure where I’m going to continue with this. I think what I did was really a test just to see what was possible and not necessarily going into production, but there is that possibility of continuing designing molds and trying to contact a company for production. I might come back to this at a later date, once there’s been a little bit more figured out about it and see how things have changed.
Q: Given the properties of the material and its tendency to crumble, what do you need to consider when attaching pieces together? What works best, glue or fasteners?
A: There are certain types of glue that can be used. For example, you can use starch based glues. The mycelium itself can also grow into things very easily if it’s an organic substance. So if it’s still wet, you can attach the pieces and they grow together on their own. There is also the possibility of having holes in things to slide other components through, so if you were to use metal fasteners or a larger wood dowel through something, that could also work, but keeping the walls fairly thick is important to make sure they don’t crumble.
Q: What about dorm furniture? no need to transport.
A: For dorm furniture, it’s not something that would be grown in a dorm itself. It’s something you’d have to bring because it needs a specific space and environmental conditions to grow. But it could be a possibility for something that people would be able to get rid of after the year. I would not necessarily want to go down that route though because then it’s using up resources to create disposable items, and I think it is a better idea to do something that’s not meant to be disposable, but that can be disposed of easily at the end-of-life.
Q: What problems do you see between making furniture for private versus public spaces?
A: I think for public spaces things need to be a lot more durable. In private spaces, you could have something that’s more of an artistic piece that you would treat very carefully, but in public spaces, nobody’s going to care about that. It has to be able to withstand daily use. In private spaces, furniture needs to be more comfortable because in public spaces you don’t necessarily want to sit somewhere for very long time, or at least the institutions that have added the furniture don’t want you to, whereas in a private space you want to be able to sit down and relax in the furniture.
Q: What types of finishes might be possible?
A: There’s a bunch of different ways. The mycelium itself can be painted with milk paint, which is a pretty easy way to go, but I’ve also seen growing mycelium into fabrics, so it’s almost upholstered right when it’s done growing, which is really interesting.
Q: Are there any firecode issues?
A: That’s actually pretty interesting. Mycelium is actually flame retardant, so it doesn’t necessarily catch on fire that easily it can go out fairly quickly. It’s also water repellent, so water just beads off.
Q: Could it be like a 3D printer with the idea that individuals could DIY on location as opposed to shipping around the world?
A: For working with mycelium on location, there is definitely a possibility that you could have molds that are a lot lighter and easier to ship than full products, and then grow the pieces themselves on location, but it wouldn’t be the same way as 3D printing a building which is done outside at a very large scale. You might have a warehouse that’s much closer to your location in which you could make these and then transport them a shorter distance, but that could be a great way to get around shipping products around the world.