Tag Archives: earthen floors

Why We Love Earthen Floors

Take one step – especially with bare feet – on an earthen floor and chances are you will be sold on the idea. You will want an earthen floor of your own. And not only will you be making happy feet when you choose an earthen floor, you’ll be making one of the most radical-yet-simple sustainable building choices… one that could dramatically reduce the environmental impacts of the built environment in a meaningful way.

earthen floor workshop and how-to

Clay, sand, fiber… that’s it!

A true game-changer
With the construction industry touting just about every option as being “eco-friendly” these days, it can be hard to know what choices really do make a difference. Earthen floors are a truly eco-friendly option. Using just four basic, natural, chemical-free and abundant materials that are minimally processed on site, an earthen floor creates a durable, healthy finished floor with the lowest possible environmental impacts. Mix the right proportions of clay, sand, natural fibers and drying oils and you’ll have a floor that is as beautiful as it is planet-friendly. The embodied energy of a 3/4″ thick earthen floor is 0.16 MJ/square foot, a tiny fraction compared to 3 MJ/square foot for hardwood, linoleum and concrete flooring of the same thickness, and 10-25 MJ/square foot for tile.

Really, a dirt floor?
It is often difficult for anybody in the “developed” world to consider an earthen floor as part of a clean, modern home. But earthen floors can be the visual showpiece of a home. A well-made earthen floor is a thing of beauty, bringing a texture and visual impact that cannot be replicated with any other material. Natural clay colours or natural pigments offer a wide palette, and a variety of fiber options can be used to great effect. And then there are the oil finishes which can add a rich lustre and additional colour options.

Are hearten floors durable?
Earthen floors are not a common option, and therefore most people do not have experience with seeing an earthen floor wear over time. In fact, these floors have very similar wear characteristics as most other natural floor materials like wood, bamboo and linoleum. All of these floor types can have a long lifespan under typical use conditions, although all are susceptible to scratching and gouging if mistreated, and all will require occasional refinishing to protect and enhance the surface of the material. Earthen floors are no different, and are quite easy to repair and refinish should some damage occur. I witnessed the earthen floor at Arts Centre Hastings spend a night under water after a large cooler full of melted ice broke, and yet after mopping up the spill the floor was not affected at all!

Place them wisely in the building
Though durable, it is wise to place them appropriately. Entryways, especially those that will see a lot of salt from snowy boots, can stress an earthen floor. Areas which will see a lot of dragging of chairs and furniture may not be appropriate. But if the use of the floor is for interior foot traffic, they hold up very well. Better see here lafurniturestore.com Design Center location sales in Los Angeles.

How does it work?
The clay/sand/fiber mix of an earthen floor may not seem like an ideal combination in a heavy-wearing scenario like a floor. These elements combine to make a substrate that can be easily packed and levelled. A typical earthen floor mix is 1 part of clay, 4 parts of sand, and 1 part of finely chopped fiber. As clays and clay soils can have different properties, it is always good to experiment with new materials before pouring an entire floor. Once this mix has been poured and troweled level, it is allowed to dry. Then the real magic occurs: several coats (anywhere from 2-6) of natural oil finish is applied to the floor. The oil penetrates into the clay/sand mixture and hardens around it, creating a tight and water-resistant finish that is very durable. The process is similar to natural linoleum, where linseed oil is mixed with sawdust. As with linoleum, the result is surprisingly solid.

Where can an earthen floor be used?
Earthen floors can be laid over many typical floor bases, including concrete slabs and plywood sub-floors. As

earthen floor clay floor how-to

A living room with a wood stove is a great place for an earthen floor

long as the floor base is stable and doesn’t have excessive flex or deflection, then an earthen floor can be laid. Typical thickness for a finished earthen floor is 3/4″, though it is possible to make them thicker. The floors can be laid over hydronic heating tubes, or used under wood stoves or other sources of heat. Simple substrate preparations are used if the base is either very smooth and shiny or if it is water absorbent.

It’s easy to learn to make an earthen floor
The steps involved in mixing, laying and finishing an earthen floor are very straightforward. If you think an earthen floor might be in your future, you can check out our upcoming earthen floor workshop, where you’ll get a chance to mix, pour, level and finish a complete earthen floor.

Earth floor workshop

The 2014 Sustainable New Construction class had their first day of hands-on learning this week when we helped Mike Henry and Deirdre McGahern install an earthen floor at Headwaters Farm.

earth floor mix

All the ingredients for an earth floor are ready to mix

The floor was installed in the basement of the new Headwaters Farm straw bale house, which is the epicentre of a permaculture/organic farm. The earthen floor will be in the root cellar area of the basement.

The day began with laying a base for the floor. In this case, the floor had been insulated with recycled foam insulation (4 inches for ~R-20), and the class formed a bucket brigade to move loads of “road base,” a well-graded and moist mix of limestone screenings intended to be tightly compacted. Given the number of people we had on the job, a lot of the compacting was achieved via good old fashioned foot stomping, as well as some tamping with a metal plate tamper.

The floor mix was based on a clay soil from an aggregate pit near Huntsville, Ontario. They provided a clay/aggregate mix that was about 1 part clay to 3 parts sand (well graded from silt to 1/8″ stone). To this, we added another portion of sand, as well as chopped straw. In ratio form, the recipe was 1 clay to 4 sand to 1 chopped straw. This mix has a heavier proportion of sand than a plaster mix. Higher aggregate for floors is something we’ve learned from Sukita Crimmel (and her new book, Earthen Floors, which is highly recommended). The sandier mix reduces cracking and helps make a stronger floor. The mix received much less water than a plaster, just moist enough that there is cohesion when squeezed or troweled.

After running these ingredients through the mortar mixer, a bucket brigade moved the mix down to the basement. We applied the mix to a thickness of 3/4″ which seems to be a “sweet spot” for earthen floors. It’s thick enough to have body and strength, but thin enough that drying times are reasonable.

earth floor mix

The mix is checked for water content

The mix is spread out and compacted with the use of wooden floats. The wood floats help to achieve a flat surface and allow the mix to be worked repeatedly without drawing the moisture and clay to the surface.

The height of the floor is checked with a levelling stick and a laser level. When the stick is placed on the floor surface, the laser line will align with a pre-set mark on the stick if the proper level has been achieved.

Once an area of floor has been smoothed and levelled, a steel trowel is used sparingly to bring an additional level of smoothness to the floor. Too much steel troweling will bring the water and clay to the surface and increase the chance of cracking.

earth floor mix

A wood float is used to smooth and compact the floor

We started installing the earth floor at around 1.30 pm and we were finished by 4.30. Many hands made for light work, and the floor was looking great when we packed up to leave. Mike and Deirdre returned to burnish the surface the next day (misting the surface and applying additional steel troweling to really smooth out the surface).

earth floor mix

Many hands at work on the earth floor

The floor will now be left to dry for at least a week, and then several coats of linseed oil (Claylin makes finishing oils and waxes for earthen floors) will be applied. Once the oil has dried (3-7 days), the floor is ready for use, or it can be sanded for additional smoothness, and a wax can also be applied.

We love earthen floors! Once you’ve experienced the feeling of an earthen floor under your feet, you’ll definitely want one…

Earth Floor Workshop Overview

Back in August, Endeavour was excited to present an earthen floor workshop with Sukita Reay Crimmel of Claylin. Sukita is a world leader in making modern clay floors, and she led a group of workshop participants in laying a floor at the home of Deirdre McGahern of Straworks.

This gallery gives a good overview of the process of making a clay floor and the workshop:

Earth floors have a come a long way over the past decade, and seeing the results of this workshop makes it obvious that clay floors are suitable in a wide variety of residential applications. We look forward to making many more!

If you’re interested in clay floors, check out Sukita’s new book, Earthen Floors: A Modern Approach to an Ancient Practice.

Seasoned Spoon Earthbag Root Cellar Almost Finished

More Trent University students may be able to eat locally-grown produce year-round at The Seasoned Spoon cafe, now that their subterranean earthbag root cellar is nearly complete.

This project is very unique, using local low-impact materials to create a food storage structure that will be able to house a range of vegetables at proper temperature and humidity levels year round, without energy intensive cooling or heating equipment.

Here is a complete set of progress photos, showing the building from start to finish:

Endeavour would like to thank the Seasoned Spoon for the chance to be involved with such a great project. Thanks also to Trent University for accommodating the build.

Tim Krahn of Building Alternatives was the adventurous and participatory structural engineer on the project, and Ben Parkes was the lead builder, with lots of help from Justin McKeiver and lots of volunteers.

We’ll post a final look at the root cellar when it’s all complete.

Earth Floors Workshop

March 26-27, 2016
9.30 am to 4.30 pm
Endeavour Centre, Peterborough

Instructor Name: Chris Magwood & Jen Feigin

Workshop Description

An earthen floor can be beautiful, durable and a joy to walk on! It is also the most sustainable flooring option available.

During the workshop, participants will learn how to create an earthen floor mix from site soils and natural ingredients. We’ll look at how to test soils for suitability in floors, and how to amend soils to make a good mix for floors. We’ll lay and trowel out a full floor, and learn techniques for getting the desired surface characteristics.

Find out about how to prepare a variety of floor substrates for an earthen floor and natural finishing options for earthen floors. Maintenance and repair issues will also be addressed.

Mixing and laying an earthen floor is a skill that is quite easy to learn, and you’ll leave this workshop eager to try out an earthen floor of your own!

Entry Requirements
Open to all

Early bird – $295
Regular – $350
Fees include healthy lunches (vegetarian and vegan options available)

Maximum class size: 12