Materials & Technology

At Endeavour, we work with a wide range of innovative materials and systems like straw bale, earthen plasters and floors, hempcrete, geothermal heating, composting toilets and more. We are always looking to try new ideas to make our projects as sustainable as possible.

On this page, you will find slide shows that examine some of the different materials and systems we develop and use.

We believe in “open source” natural building. Sharing our experiences, both successes and near-successes, helps all builders to benefit from the steep learning curve on the leading edge of sustainable building. We hope you find these slide shows useful introductions to these building approaches.

Check in frequently, as we continue to try new things and make our documents available here.

Round bale columns

Many people use small, square straw bales to make buildings, but we used the big round bales as load-bearing columns in a building! The big rounds are incredibly dense and uniform, and we lab tested them to 120,000 pounds of load! They are quickly and easily assembled and make a truly sustainable “frame” for a building.


Download Round Bale Column Presentation (PDF)

Prefabricated straw bale walls

Straw bale walls have a remarkable array of benefits, but they can be labour intensive and are difficult to build in a mainstream context. By prefabricating the plastered straw bale panels, they can be delivered to a job site for the same cost as conventional framed walls, and still have all the environmental benefits. And they can be produced quickly and easily in small, local micro-factories, making it possible to bring the benefits of bale walls to any region.


Pre-fabricated Straw Bale Walls – 8MB (PDF)

Tire piers

Used car and truck tires are a waste dilemma in our society. Why not put these tires to use as structural elements in our buildings? We have used tires to create pier-style foundations, creating strong, long-lasting foundations that cost very little to make!


Download Tire Pier Presentation (PDF)

Waste wood structural columns

There is an incredible amount of “waste” wood that is thrown into landfills or otherwise left to rot because it is not long enough to be used vertically in a building. So we take that wood and stack it up to make load bearing columns in buildings. Offcuts from log home factories, discarded 2x4s and 2x6s and dead tree limbs all find permanent, structural homes in our waste wood columns.


Download Waste Wood Columns Presentation (PDF)

Clay Plasters

Clay plasters are one of the most remarkable materials available to sustainable builders. Structurally feasible, widely and locally available, low cost, durable, healthy, endlessly repairable, easy to apply and offering a gorgeous range of finish possibilities, we love clay plasters at Endeavour. They are featured on every building we make. From chunky body coats to fine, thin finishes, they are essential to our work and offer huge environmental benefits if adopted more widely.

Composting Toilets

Whether they are simple bucket toilets, stand-alone units or remote chamber composters, these toilets are essential to a truly sustainable building. By eliminating contaminated blackwater from sewage systems we greatly reduce pollution of ground and surface water, reduce the amount of fresh water required by a building and turn human “waste” into valuable compost. It’s one of the biggest steps we can make towards sustainability.


A lot of the wood we harvest for building is not suitable for milling into dimensional lumber, but cordwood (or stackwall) construction can make use of smaller, less straight and less coveted species to make solid, simple walls at a very low cost. Especially when laid up with cob (mud) mortar, these walls are very sustainable.

Earthbag foundations

It’s hard to beat earthbag for low-cost, low-impact foundations. The basic materials are cheap and easy to come by and the process is simple and straightforward. It makes using rammed earth practical! We’ve used earthbags in many of our foundations… it is one of our essential building blocks at Endeavour.

Earthen floors

Earthen floors are like a hug for your feet. The leather-like consistency of a finished earthen floor is like nothing else. They make for durable, affordable floors with a very minimal environmental impact. While it’s important to get the mix and the finishing right, an earthen floor is quite straightforward and an excellent addition to the sustainable builder’s toolbox.

Geothermal heating

Geothermal heating (better referred to as “ground source heat pumps”) can be a great way to provide heating and cooling without the direct consumption of fossil fuels. The heat pumps work like your refridgerator, using a refrigeration cycle that operates at the year-round ground temperature of approximately 10 degree Celcius. If you’ve ever put your hand on the warm radiator behind your fridge, you’ll appreciate how heat can be extracted by a heat pump!

Green roof

A green roof can have many sustainable benefits, including the mitigation of stormwater runoff, providing natural habitat, keeping buildings cooler in the summer and protecting roof membranes.


Hempcrete is a mixture of chopped hemp stalks, lime and water. Mixed together, they make a remarkable material! Mixes can be dense enough to make structural foundations (that are self-insulating) and light enough to make a high R-value wall insulation. No matter how it’s mixed, hempcrete has a unique lightness and cohesion (most mixes will take a screw!). It’s already finding commercialized applications in Europe, and we hope our work will lead to the same kind of adoption here in North America.

Natural finishes

Natural finishes include a vast array of possibilities… finishing interior and exterior elements of a building with natural materials encourages creativity and resourcefulness, and can result in beautiful, stimulating buildings that are healthy, local and unique.


Photovoltaics (PV) create electrical energy from sunlight. They are a low footprint means of generating electrical power without the use of fossil fuels, and are an integral part of our Endeavour projects. Here in Ontario, Canada we enjoy a great Feed In Tariff program from our utilities that pays building owners a premium for solar generation over a 20-year contract.

Radiant heating

Heating that is delivered through the mass of a building can be very comfortable, efficient and healthy. Floors and/or walls can be effective radiators providing constant, stable indoor temperatures. A wide range of heating sources can be matched with radiant delivery, making it adaptable to conventional heating systems or more sustainable heating options.

Rainwater harvesting

Most buildings offer enough roof collection area to supply most or all of the water needs of the occupants. Rainwater can be clean and abundant, and using this resource relieves pressure on ground, surface and municipal water supplies. Some basic equipment ensures the harvested water is quite clean, and treatment systems to bring it to potable status are affordable and available. Becoming water independent is a huge step toward sustainability!

Solar hot water

There is no better, more cost effective way to actively capture the energy of the sun than to heat water. Our systems have been used to heat domestic water and provide some space-heating load too. Sometimes we use commercial systems with controls and pumps, and sometimes we use simple, homemade thermosyphon systems. We’ve even used non-electric bubble-pumps! However they are configured, these systems are an integral part of a sustainable building.

Straw bale walls

We love straw bale walls at Endeavour! Warm, simple and beautiful, we build them load bearing, in a host of different lightweight frames, or matched with timber framing. We have a particular fondness for dipping our bales in clay slip before installing them, but not always! Flat and straight or curvy and wavy, we use bale walls because they offer the best insulation, the easiest installation and the lowest environmental impact… a great combination.


The effective and natural insulation of straw combined with the excellent moisture characteristics of clay can make for terrific wall insulation. Known as light clay/straw, straw/clay or slip-straw, this is an old insulation technique that is deservedly being revived. Packed lightly within a formwork on a frame wall, straw/clay is an excellent substrate for plasters and a healthy, low-cost, low-impact insulation.


Thatching roofs has a long, proven history in most parts of the world, but not so much in North America. However, the invasive wetland plant phragmites is becoming abundant in marshy areas in our region, especially along the sides of highways. We harvest the invasive phragmites from local roadsides and use it to create beautiful, long-lasting and low-impact roofing!

Timber framing

Timber framing is a time-honoured craft practiced around the world. The abundance of wood in our region makes it a sustainable practice, especially as we often use found, unmilled logs and recycled timbers in our frames. The handcrafted joinery is strong and long-lasting, and timber frames work well with a wide range of natural foundation, wall and roofing systems.