Revolutionizing the Way Walls are Built with Biocomposite Materials
Monty Chong-Walden is the co-founder of Calmura Walls, a company that is proposing a different way to build homes. By utilizing natural and recycled materials, Calmura Walls has developed a monolithic biocomposite wall system that is durable, lasting, and healthy. In this interview, Chong-Walden shares his inspiration behind starting Calmura Walls and how this led to the creation of their unique wall system.
What was the inspiration behind starting Calmura Walls and the development of your wood waste products?
Monty Chong-Walden: I have always been passionate about doing things better for the earth. Also, I studied engineering and have been interested in architecture for a long time, and I ended up working in the building industry for quite a while. One of my previous companies produced custom projects with lake rescued woods, which are ancient logs that have been pulled out of lakes in rivers in North America. We would take the lumber and make custom products for high-end restaurants and homes in North America. I got fascinated by that kind of idea and was searching for the next thing I wanted to work on.
In 2014, I came across Hempcrete being used for building in Europe. I was reading about this wonderful material and thinking “why we do not have this here in North America? Why isn’t everybody building with this fantastic material?” So, I did some research and I found various things happening in Canada. One company in Calgary, Just BioFiber, had started to create a hempcrete structural blockJust after I discovered them, I found that they were going to be in an innovation show here. So, I met the team and I started working with them. I also found a builder here, on one of the islands close to Vancouver, who had been building with Hempcrete for about three or four years. He built his own hempcrete house, and I started working with him too. I was very excited about it, so I told my friend, now my business partner, as he was looking to build a house at the time. I started talking about different ways to use the material and trying to make it easier for people to use it.
The common practice is bringing raw materials to site to mix and cast in place, which is a slow process and demands lots of labor. We started looking at how we could improve this method. We knew in Europe they were making blocks or bricks. So, my friend came up with the idea of making panels with an infill. The panels would be made in a factory, so it would be much faster and much easier for people to use. My friend then challenged me to write a provisional patent in a month, which I did, and we submitted it.
After that, it has been a long track. This was in 2016, seven years ago. I have always been interested in architecture, but not the materials that were being used, like drywall or fiberglass. These cheap materials just didn’t make very good homes and required complicated building science to prevent rot and mold. When I came across Hempcrete, I could see that it would make really solid, durable, lasting, and healthy homes.
We really wanted to build with hempcrete, but it was not readily available, so I thought “if nobody else is doing this, I will, because somebody has to.” I sold the home I had, to have some development money, and then rented a place with a garage, so we could start the research there.
What is the concept of your wall system and how does it differ from conventional wall systems?
Monty Chong-Walden: Our company focuses on changing the way walls are built. In North America, we typically use sticks to build wood frame houses, and then we cover them with layers of materials like drywall or plasterboard, plywood, and insulation made of foam or fiberglass, protected by layers of plastic wrap and tape. These materials cannot be recycled, so they end up in landfills, which is a significant waste problem in construction.
We wanted to move away from conventional materials that are used around here in Vancouver and use natural materials that were traditionally used before. And so rather than making walls with all these layers, our wall system is a monolithic biocomposite wall that can last for a very long time. It is similar to a cob wall or adobe, but we have modernized it so that it can be built quickly and efficiently, using materials that are factory-made. This means that architects, engineers, and inspectors can easily assess the performance of the wall system, and that it can be replicated with consistent results.
We are not trying to disrupt the way homes are built here, which is mostly by building on site. What we are changing is how that wall assembly goes together. Our wall system is made of recycled materials, including forestry, agricultural or even deconstruction waste.
How do you use the recycled materials?
Monty Chong-Walden: In 2017, I went to the International Hemp Building Association conference in Montreal, where people presented research on using other materials as bioaggregates like rice husk, artichoke stalks and agave plants, not just hemp chips. So, in our research at FP Innovations, which is a forestry products innovations lab at UBC, we were challenged to look at the comparison between using hemp hurds and using wood. We have lots of wood waste in BC, as there are lots of forestry operations. So we thought that using wood waste was more sensible than hemp.
Actually, the people from FPInnovations laughed at us when we told them what we paid for a supersac of hemp hurd, because we had to bring it in from Alberta. They said that for the price we could probably get a whole container of wood waste to work with.
So our research centered around using wood waste. While we can’t use it structurally, we could chip it up and make it into a better building product.
Building science now has been shaped by cheap materials to where we are basically wrapping our homes in two plastic bags. We have a plastic bag on the inside to keep the moisture from going into the wall from the inside, and we have a plastic bag on the outside to keep moisture from going into the wall on the outside. So, our thoughts are “why don’t we just have a vapor open wall, like we used to have, that would breathe, and when the water gets in, it can get out, and we can live much healthier?”
It has been quite a journey in understanding and realizing all this. But from the get-go, I looked at this material and thought, “this is an amazing material. I would love to work with it.” As I couldn’t get it, we tried to create it.
Where the wood waste used in your research comes from, and which industries and areas are involved?
Monty Chong-Walden: So far, all of our research and production has been lab-scale, and we are currently looking into pilot-scale production. For our initial testing, we used wood waste that we could find around FPInnovations. We tested all kinds of wood waste, including pine, cedar, and Douglas fir. Most of the waste we used came from plywood veneers, which expire if not used in a certain time frame. We chipped up these veneers to create the small chips needed to mimic the hemp chips.
As we tested different woods, we found that the highest value waste was western red cedar. We used 5 mm veneers of western red cedar that had been graded out from what it would typically be used for. We also used fence board cut-offs, which are typically straight and square, and any parts that were cracked or had knots were cut off and discarded. These cut-offs ccame from an ever-growing pile, so we were able to gather them up and use them in our lab-scale production.
As we move forward, we will be looking for a strategic partner with waste we can volorize to help establish a pilot plant, which will determine what types of wood or agricultural waste we will use in larger-scale production.
Our mission is to find ways for people to build more with locally-sourced natural materials, rather than relying on conventional building materials that are transported from around the world. We’re trying to bridge the gap between very local site-built methods, and mass-produced low-value materials, by creating regionally produced materials, making it more accessible for people to build with natural alternatives. Our product consists of clay, lime, and wood, or other bio aggregates, so that when the building’s life is over, the materials can be returned to the earth, feeding forests and fields. Moreover, our resources sequester biogenic carbon (the carbon captured by plants). By using natural materials in construction, we can create a more sustainable building industry, minimizing harmful toxins, emissions, and waste.
Are there any particular types of buildings or construction projects that your wall system is best suited for? Is it possible to use them in retrofit projects?
Monty Chong-Walden: Here in Canada, we have seen hempcrete being used in the restoration of old, wood frame and stone buildings. The material has been found to be beneficial because it keeps moisture away from wood, which helps preserve it and prevents pests from getting into it, as opposed to using concrete-based infill.
People were doing renovations and restorations with this material. However, what we envision is that our material could be used alongside any structure. Our material isn’t structural, so basically, it can be put around whatever structure you have. We are targeting residential projects, but we plan to expand to multi-unit residential buildings or taller buildings.
Currently, we are focused on working with mass timber architects and builders since our panels could help protect the wood from fire and be used for sound insulation for floors and ceilings, not just on the walls. So, our product could go alongside those mass timber elements to help protect them.
When we looked at what had been done in the hempcrete industry, we saw bricks and blocks, but they don’t work well around wood framing, which is a very common construction system in Canada. So, we thought about designing it differently. We developed modular panels of 600mm x 1200mm, with various thicknesses. They are lightweight yet durable and easy to work with. By making the panels we now have a platform product that can be used in a number of ways: they can be used for floors and ceilings, and can be attached to the face of mass timber, like CLT panels. If you want to build a wall system, you can use them on either side of the wood framing, using whatever natural fill you want, like wool insulation or hemp fiber batt insulation. We also discovered that we could foam our biocomposite mix and pump it in to fill the wall cavity, resulting in our patented monolithic wall, which is much easier and faster than traditional methods.
Looking ahead, what are your plans for expanding the reach and impact of Calmura Walls, and how do you see the sustainable building materials industry evolving in the coming years?
Monty Chong-Walden: I think the potential for Calmura Walls is massive right now. There are so many opportunities to expand its reach and impact. However, part of the challenge is getting the industry to wake up to the potential of sustainable building materials. The construction industry is notoriously slow to change, and it has become heavily invested in conventional building materials. But we are seeing changes happening, and we are working to expand what we have accomplished at lab-scale.
The conversation is shifting towards embodied carbon in building materials and reducing energy usage in buildings. There is more talk about moving away from steel and concrete and using mass timber, and that is where our product fits in really well, initially as sound insulation on the mass timber panel floor, but also on the walls. Our panel could be used in many different ways to create biobased buildings and natural buildings.
The biobased materials industry has grown significantly in recent years. As the industry grows, and the supply chain for industrial hemp expands, there will be more and more companies like ours. We want to be part of that growth and a leader in that space, proving that there is a different format for sustainable building materials. It’s not just about bricks or blocks or full wall sections, but also panels that can be used in many different ways to create sustainable buildings.