The Layers Beneath Our Feet

We built our house on the top section of a bedrock slope – a perfect place for anchoring the house to a solid mass.  The concrete stem walls are pinned directly to the rock in a way that reaches around and flows over the various natural undulations that existed, allowing us to avoid any blasting.  At the south side, where the slope falls downwards, the cavity in which we back filled with shale was about 8 feet deep, and on the north wall side, it was only 2 feet.  An earth berm set back from the over hang of the roof lifts another 2 feet the length of the north wall, providing a small shawl of soil around the chilly side.  We had learned from Michael Reynolds and his design features that the planet Earth is a thermally stabilizing mass that delivers temperature without wire or pipes, and we wanted intuitively to be connected to that constantly warm, grounding energy.  “The outer few feet of the earth heats up and cools off in response to surface weather. However, deeper in the earth, about four feet and beyond, the temperature is more constant (around 58 degrees). Here, the earth can be used to both cool and stabilize temperature if the home is appropriately designed.”  earthship.com/comfort-in-any-climate.   So the fill of local shale went in, packing solid down to the bedrock below.  While it is not a true tapping in to the mass temperature of the earth, (instead of digging down, we filled the ground in below us) it felt better than an awkward crawl space and manufactured insulation.  On top of the shale went our vapour barrier of plastic, on to which we needed (by code)  a layer of insulation. Most common here is the pink foam board, but we looked around and found that mixing agriculture grade perlite with a modest amount of concrete (6 shovels perlite to 1 shovel concrete) and laying it 4 inches thick gave us the same value to code as the pink stuff.  We could also neatly pack it in around all the water pipes that we put down on the plastic layer.  We were able to easily anchor the hydronic in-floor heating pipes to the perlite layer before we continued up with a 3 inch thick cob slab as a sub floor.  We had a bobcat mix all that up for us and we hauled it in and trowelled it in place as level as we could get it.  Our original plan at that point was to finish it off with an earthen floor everywhere except in the kitchen, bathroom, mudroom and utility room, where we would tile instead.  Our search for cheap tile however, was fairly unsuccessful, as was our search for a trusted earthen floor recipe and method description.  Our time was being pushed as was our wallets, and at some intersections of journeys, there come times when priorities begin to change places.  Our three years in the trailer was wearing us thin, and with Colin back at work to uplift our bank account, time became scarce as well.  Accomplishing 800 square feet of earthen floor became daunting and expensive as we waded through the estimates of finishing oil and wax, kaolin clay and stucco sand.  Then I stumbled upon a place in Vancouver that was selling ecologically certified cork flooring at a ridiculous cheap price compared to other prices we had collected, so we put in an order that would cover all but the very front south facing room.  Colin was determined to make an attempt at an earthen floor in the room that receives all the passive solar sun, so as to keep the principle of mass heating intact without too much expense and time.  The cork flooring was beautiful to install- an interlocking system that floats above the subfloor, allowing for expansion with the temperature fluctuations of the in-floor heating.  Of course, because the cork was not as thick as we had planned for with the earthen floor, and the sub floor not at all level enough for cork tiles, we had to trowel an inch of concrete on to the whole area.  The cork floor is durable and flexible, warm and soft on the feet.  The earthen floor section was indeed another journey of experiment, a journey which I will write about in another post dedicated entirely to the process of the art of earthen floors.  We are glad to have only done the one small section, but we are also excited about repeating the process in the second half of the house.  It is wonderful to have the opportunity to test the methods that we are choosing on this half of the house, so we can learn from our experiences and navigate with more knowledge for the second half of the house.

Final Plastering

This summer, we have finally completed the last layers of the inside wrap of the house, including all the flooring and the final coat of clay based plaster on all the walls.  This last layer of clay plaster was much more particular in recipe and in application than the rest of the rough layers, and calls for it’s own chapter in explanation.  (I have already outlined the procedure for the rough coats of plaster in a previous posting, Natural Plaster.)  I would like to express my understanding of our process in openness to the many other recipes, methods, and materials that have been used with success throughout time and in many different places.

My experience is limited to our one house here on the west coast of Canada.  However, we have also been guided by our friend Tracy Calvert who has compiled her own knowledge and experience and has willingly and generously passed it on to us throughout our journey.  The ingredients in the recipe that we used are kaolin clay, stucco sand, fine straw, whiting (calcium carbonate), paper pulp, rice flour, and a small amount of borax and white glue.  The Kaolin clay is a fine powdered porcelin clay that was purchased at a pottery supply store, as well as the whiting, which is basically a chalk filler.

We used finely chopped straw left over from baling, but we also used an alternate fiber material of bulrush down, the fluffy insides of cattail heads harvested before they turn inside out.  The sand is just fine washed stucco sand, and the rice flour is mixed with hot water and made into a glutinous paste.  We soaked newspaper overnight and then pulped it up with our paddle mixer, which we used to make the plaster in buckets.  Ratios are as follows :  6 parts sand, 4 parts clay powder, 2 parts whiting, 1 part straw, and 2 parts paper pulp, 3/4 part rice flour mix,  a handful of borax, and two or three glugs of glue.  One part for us was a 1 1/4 litre bucket.  First we dry mixed in 5 gallon buckets the sand, clay, whiting and straw, then added the paper pulp and enough water to make the mix spin easily but stiffly.

Because we were going to wait to plaster the next day, we left the mixes at this stage overnight.  When we were ready to plaster, we added the rest of the ingredients and any colour pigment we were using, then compiled three of the buckets into a big tub and mixed them thoroughly together.  This helps with consistency of ingredient quantities as well as getting the bottoms of the buckets mixed in well. For colour pigments, we did some test samples using tablespoons of pigment to 1 litre of mix, then allowed the samples to dry to the finish shade.  We then multiplied the tablespoon quantity for the amount of litres in the 5 gallon buckets (some estimating was definitely relied upon) and added that amount of tablespoons of pigment per bucket.  Finally we were ready to put it on the walls!  We sprayed the walls with water to help bond the two layers together, then considered how to plaster each section without stopping or ending up with long edges of plaster that are left a little too long and begin to dry out.  Unlike the regular clay plaster, there is only so much re-wetting that the plaster can take before it is too difficult to smoothly work new plaster up to it without leaving lines or smudgy areas.  This sensitivity to time makes considerations of temperature and air flow quite important, and usually requires two or three people working together for smooth going.  We had two of us plastering, and one person in charge of mixing up new mixes, moving ladders, bringing coffee, keeping the music flowing, and generally making it possible for us to keep working our lines until a section is done.  We spent almost five days in total plastering the whole inside of our house, which worked out to be about 1200 square feet of wall and used approx. 27 buckets of mix  (one mix being one recipe.)  We used japanese trowels, bought through the internet, and homemade hawks (rectangles of plywood with a handle on one side), as well as a few smaller tools for tight corners and edges, and yogurt lids with the rim cut off for shaping curves. Generally, we covered an area with overlapping rainbow swipes, then flattened them all down in larger sweeping motions.  We plastered over drywall as well, which we had prepared with glue and sand to provide a grippy surface.

All the kickboards and window and door trim were put in place first so that the final plaster came to meet the trim and seal any spaces.  We also tiled the sills of some of the windows before hand.  At a certain time of dryness, we went over the whole wall with a damp sponge to blur any lines and troweling marks, then at another certain point in dryness we burnished the whole wall with a yogurt lid.  This brings up the clay and pushes in any sand, and gives the plaster a certain polish that makes it more durable and smooth.

We are so happy about our earthen walls, from the clay slip through the rough coats and finally plastered with the finished layer.  I began this house knowing absolutely nothing about natural plaster, and although it took lots of work and patience, it provided a full scope of learning the art of earthen plaster.  There is always more to learn, and I look forwards to continuing on and developing my methods and skills throughout the second half of the house.  I am so very grateful to Tracy for leading us on this path and providing support as well as space for us to take it on and call it our own.  The passing on of this type of skill is important to her as we share and expand our self- sustaining abilities for building beautiful and healthy homes.

Eco-Homes Tour and Symposium

A comment that we hear regularly from those visiting our strawbale house is that not everyone who wants to have a naturally built house is capable of doing it themselves.  Indeed, it takes a lot of hard work, research, material searching, building skills, tools, and time to go through the process as a home builder of any type of project.  Anyone without such prerequisites but with a desire and willingness to learn certainly can go for it, but there are many out there for whom it is more realistic to hire someone else to build them a home.  This is prevalent within the conventional building industry, but where does one look to find a straw bale crew?  A natural plaster expert to source materials and use their knowledge of crafting healthy walls?  What about an architect who will consider the natural light and water conditions of your chosen spot?  All of these job positions are readily available for the standard house, but difficult to find for alternatives.

On Pender Island, a group of people wanting to promote various aspects of natural building have formed the Eco-Homes Network, in hopes of being able to provide services and information for anyone seeking to build a healthy home, as well as networking with other builders in the community to create a greater awareness of alternative materials and systems.  Education for clients as well as builders is a large step towards integrating healthier building practices into any house or project, whether it is classified as “eco-friendly” or not.  Why limit ourselves with labels and categories?  Any system that takes pressure off the resources of the earth and saves money in the long term is just a good idea to consider.  The Eco-Homes Network consists of Rob Zuk – a solar systems consultant, Ken Rempel – an architectural designer, Garrett McLeod – a traditional timber framer and carpenter, Colin Hamilton – artistic woodworker and natural builder, Tracy Calvert – an extensive natural builder and master of earthen plastering, and Jude Farmer –  a woodworker and man of many skills.  In fact, everyone in the group has many crossover skills and knowledge spanning many years of different experiences within the building industry, including roofing, tiling, stonework, workshop leadership, landscaping, flooring, and planning.

For two years, the Eco-Homes Network has set up a demonstration zone at the Pender Fall Fair and has hosted an eco-homes tour as part of an effort to educate people about natural building practices, and to showcase the many beautiful homes around us that incorporate different aspects of the industry.  At the Fall Fair, everyone has been invited to squish their toes in cob and plaster mixes, and try their hands at spreading the mix over a demonstration wall of bales in a timber frame.  There also has been many books to gaze through, knowledgeable people to talk to, and a photo board of projects to look over.  Many people get a good sense of the simplicity, creativity, and beauty that encompasses the building of a natural house.  The Eco-Homes tour, which takes place a week later on Labour Day, is a self directed tour of up to 10 houses around the island, and has showcased houses made with chip-slip walls, strawbale, cob, cordwood and Faswall blocks (compressed recycled wood chip blocks), and including features such as earthen floors, living roofs, natural plaster, rain water catchment systems, hydronic in-floor heating, solar hot water, passive solar, composting toilets, and countless other details and creative touches that make up a complete picture of a natural house.  Some of the houses have been in the construction phase, allowing visitors to see the layers of some of the processes.  There have been over 150 people from the locals to travellers from the mainland and Vancouver Island each year, asking many questions and hopefully taking some ideas back to their own homes.  All proceeds from the previous tours have gone to the Pender Community Hall and to the Pender Island Farmland Acquisition Project.  This year, proceeds will help the growing Pender Community Transition movement, to build a more sustainable island.

The Eco-Homes Network is adding a new element to the tour this year.  On Sunday, September 4th, The Building Around Water Symposium will be a day  focusing on water systems and living roofs as well as a mini tour featuring houses with such systems for viewing.  The six houses on the tour will be open for visitors in the morning, then symposium events will be commencing at the community hall in the afternoon.  All the homes are located along Port Washington road, within a few kilometers of the hall, and would make a beautiful morning walk, jog, bike ride, or car stop!  Lunch will be available for purchase at the hall at noon, with speakers beginning at one o’clock.  Water on the gulf islands, as well as in many other climates world wide, is a concern needing immediate addressing and rethinking in terms of efficient usage and collection systems.  Droughts and shortages have become more widespread as our climates shift, reminding us of the valuable place that water holds in our lives.  Adam Scheuer, president of Water Tiger Rainwater Harvesting, will give a talk and answer questions regarding rainwater collection systems.  Living roofs are a great way to incorporate water catchment, as well as maximize water absorption and minimize water evaporation while providing more habitat for birds and bees.  Living roofs are gaining lots of attention as features of large commercial scale developments, but they are also beneficial for residential homes, and so there will be a presentation on the installing and maintenance of green roof systems.  In our marine climate zone, there is much concern around the use of vapour barriers.  Many alternative wall systems, such as strawbale, cob or chip slip, provide a breathable wall which does not require a vapour barrier but does now require an envelope engineer such as Ben Martin, who will talk about designing and building with thermal mass wall assemblies, vapour barriers and codes.  Starting at 6:30, there will be a show and tell slideshow by our local builders demonstrating their own creative, recycled, sustainable, and artistic projects.

Building with Pop Cans

One of our very first introductions into the world of sustainably built and functioning houses was in Colorado where we attended a presentation by Michael Reynolds, an experimental architect/builder from New Mexico.  Michael is well known for his Earthship buildings, which are built with recycled materials and designed with self- sufficient systems of water, heat, cooling, and light.  They are like permaculture houses, where each aspect of design is multi-functional and supportive to other systems.  These are not high-tech modern houses with computerized regulators though- they are designed with the observations and functions of nature, such as passive solar, complete water systems from rain to grey water recycling and irrigation within the house, sewage treatment, natural light, and air flow circulation that follows natural patterns.  Michael had also taken the important step of building these houses with materials that would otherwise become garbage, like car tires, plastic bottles, and aluminum cans, among other things.  He has taken these ideas and travelled to impoverished countries, demonstrating the possibilities of creating cool, water capturing, ventilated houses for those in hot countries with no electricity and clean water, built with free materials from overflowing garbage dumps.  Despite much conflict with the states’ building industry on the parliamentary level, Michael has continued to fight with a  passion to build healthy, non-dependent homes that span classes and climates.  An awesome documentary called Garbage Warrior follows Michael through his dreams and his journeys.  Check out amazingly beautiful houses and innovative design principles at this site, Earthship Biotecture Green Buildings, http://earthship.com/.

Colin’s design of the bathroom has a round shower space situated almost in the middle of the house, with a tight curve that would be difficult to frame out of wood.  So we used Michael Reynolds’ technique of creating an interior wall out of pop cans, mortared together like bricks in concrete, which made the curve easy to achieve.  Every once in awhile we placed two glass bottle ends taped together into the row to let extra light in, since there are no windows at all in the bathroom.  We had collected a bunch of square, blue gin bottles from the recycling depot here, and instead of trying to cut them we placed them upright around the top, which ended up giving our round wall a bit of a castle turret look.  We placed the height of the wall at just over 6 feet high, so more light can come in over the top.  Colin built a wood cap that sits an inch wider than the wall so we can put plants up there, and the  outside of the wall got a layer of clay plaster, and will be finished with the same earth plaster that the rest of the walls will have.  On the inside, Colin plans to build a small seat in the corner out of cans as well, and we will then coat the whole inside with red pigmented concrete, leaving the glass bottles exposed and glowing.

The Living Roof- One Year Later

I like to imagine the view of my house from all the places in which any living thing may be gazing.  Before the population explosion of humans and the development of the shelters we build for ourselves, the view from the sky would have been quite a different scene.  With uninterrupted tracts of habitats absorbing the sun and the rain and providing possibilities of nesting places and food, birds and insects had much more to choose from.  Roofs, of course, aren’t the only dead spots in bird and plant habitat, but they are thankfully gaining recognition as an important factor in green building design for homes as well as for commercial and industrial scale buildings for many reasons.  Despite their centuries old history in Scandanavian countries, green roofs are just coming into modern construction as cutting edge eco-design around the world.  In 2008, the Vancouver Convention Centre installed a six-acre living roof of indigenous plants and grasses on its West building, making it the largest green roof in Canada.  Combating the urban heat island effect is one reason for creating a green roof –  traditional building materials soak up the sun’s radiation and re-emit it as heat, making cities at least 4 degrees Celsius (7 °F) hotter than surrounding areas. On Chicago’s City Hall, which features a green roof, roof temperatures on a hot day are typically 1.4–4.4 degrees Celsius (2.5–8.0 °F) cooler than they are on traditionally roofed buildings nearby.  As well as adding insulation value, green roofs decrease the total amount of runoff and slow the rate of runoff from the roof, retaining up to 75% of rainwater and gradually releasing it back into the atmosphere via condensation and transpiration. 

Our little 900 square feet of living roof is certainly small scale compared to the big picture of global sprawl, but it falls into our value of every little drop creates the ocean.  We still have two more roof sections when the rest of the house is built, and we plan on planting those up as well.  For a description of how we constructed our green roof, please see the older post in the Natural Building category called The Living Roof.  We planted the plants one year ago and I have been pleased with the growth of the many varieties, which have spread considerably and seem to be greatly enjoying the view as they take turns flowering.  We used many clumps of stonecrop which were growing on the rocks where the foundation was to be built, as well as hens and chicks, sedums of varying colourations, ice plants, and a few other varieties of winter hardy succulents that I am not sure what they are.  All the plants were propagated from friends’ gardens, given as gifts, or collected from the property.  I haven’t done any watering and I figure that whatever doesn’t survive in the natural climate just won’t have a place on the roof.   Along the center spine of the roof, I set the stonecrop in a large infinity symbol, with the hens and chicks filling in the circles.  Most of the stonecrop flowered, creating a lovely yellow outline, and I hope that in the next few years this symbol will become more defined as an offering to the element of the ethers, and to the winged creatures that I hope will stop for a rest during their journeys across the skies.      


The Truth Window

A traditional feature of strawbale houses is the truth window – an opening through which one can see the straw inside the walls.  Like every strawbale house, truth windows are unique and creative, providing a little peek into the golden stems.  Truth windows often take on the role of an altar, bringing gratitude for the sources of our materials and reminding us of the reasons for the choices we have made.  We have seen truth windows as elaborate wood frames, recycled metal grates, little doors that open to reveal the straw, and anything in between.  We went through a few different designs before we finally settled on the simple use of the clay plaster as a sculpting medium in which to frame and hold in place the piece of glass against the bales.  I decided to build out the bottom of the frame to create a small ledge in which to place little treasures, much like the objects that adorn an altar.

First we trimmed out a recessed area of the bales by about 4 inches and set the glass in place.  I used a pair of chopsticks to help hold up the plaster that would shape the top curves of the frame, then applied a first coat of plaster.  With the second coat of plaster, I built up the shape that I wanted in the curves, and added the little reveals above and below the frame.  The beautiful thing about such a sculptural style of building is that you can really make it up as you go, erasing and starting over, correcting and being surprised by what happens.  I haven’t done much sculptural work in my past, so getting the picture of what was in my head on to the wall was an interesting challenge of dexterity and a good lesson in flexibility.  What the truth window ultimately ended up being was a combination of a vague idea and surprise.

For the finish plaster,  I used the coloured plaster that Tracy and I had made up for our colour samples for the front room.  We ended up with a beautiful orange that was too dark for the whole room, but would make the truth window stand out against a lighter shade of the same colour.  We haven’t done the rest of the room yet, but we are working on getting all the other prep details done so we can do the final plaster sometime in July.  So for right now, our finished truth window sits lovely and peaceful amongst the strew of construction and chaos.  We look forwards to sitting just below it, eating our meals and rotating our treasures in gratitude for the soil, the sun, the rain, the seeds and the hands that cared for what has become the walls of our home.      

The Timber Frame

The support structure of the house is a traditional wood jointed timber frame.  This post and beam style of framing easily suits the in-fill strawbale walls and lends it’s simplistic beauty to the interior of the house.  Colin worked with Garrett McLeod, a Pender woodworker and friend to design the structure of the frame to fit the shape of the house that Colin designed.  Instead of the traditional barn shape with a peaked roof that appears in most timber frame designs, we wanted a single level design with more of a japanese tori style configuration, allowing for the gentle curve of the living roof in the front and the shed style roof of the back half.

The Douglas Fir beams for the frame came from Gary Bruce, a wood timber salvager from Vancouver Island.  He delivered our order on his flat bed truck right into the temporary tent of the work zone.  We used 6×6 posts and 6×8 beams, with the main center beam being a beefy 8×8.  The engineer we called on to approve the structure determined that we wouldn’t need to use any knee braces with these sizes, but we threw in a few corner ones anyways.

Garrett and Colin worked on shaping the joints from the end of August, 2008, until they began putting up the first posts in the beginning of October.  The skill and efficiency that Garrett brought to our project was highly admirable and appreciated.  He had just finished a timber frame course at The Island School of Building Arts, on Gabriola Island,  www.logandtimberschool.com/.  Colin used his own skills from the  joinery that he uses in his woodworking business as much as possible, although the mortise and tenon cuts were of a much larger scale!  The whole frame went up in 6 weeks, using only a hand-crank frame that Garrett built to hoist the horizontal beams into place and so keeping with a completely engine-free process.  We did use Colin’s pick-up trunk attached to a block and tackle to lift the north wall bent all in one go with a few helpful neighbors, just like an old fashioned barn raising.  We love the beauty and strength that the timber frame has given to our house.  With the bales wrapped completely on the outside, the timbers are completely revealed against the walls on the inside of the house.  The beautiful honey colours of the fir were enhanced and sealed with a natural wood finish called Land Ark, which contains beeswax, tong oil, linseed oil, citrus extract, and pine rosin.  Land Ark is made with only natural, non-altered ingredients from sustainable resources, without chemical processing, bleaching, or harmful additives.  We have also used it on the door and window trims, the baseboards, and the ceiling boards.  It actually feels great to get on my skin, and I love the smell of it as I have done much of the staining.

The art of timber framing has a long and wide spread history of building, and we are very proud to have been able to utilize such a naturally complete system of support using the simplicity of the integrity of the wood itself in the fantastic configurations of joinery.  Timber framing is another way of demonstrating that beauty and art can be a deeply integrated way of construction.  To honour  the trees’ offering to provide their wood for our shelter (even though it was reused), we gave our gratitude in a traditional ritual of nailing a young sapling to the finished frame.

Have Bales, Build Walls

Colin and I explored and learned about many alternative building materials, but strawbale construction was not one of them.  The closest we came to seeing them in use on the west coast was as a north wall in a hybrid house with a southern cob wall.  It made sense- cob being a poor insulator but with beefy, heat sink mass wall, and bales being great for insulation in places that receive little sun.  Strawbales have been reported to have an R value (insulation measurement) of anywhere between 30 and 60 (with code minimum being 25 here).  We also learned that such decisions should ultimately be made when the land is chosen and the building site has been  observed for weather patterns, with an open mind free from any construction type bias.  We first considered strawbales when we began asking around to people in our community, and found a few existing strawbale houses, and one friend in particular who has built with many different types of alternative materials.  Tracy soon became our walking resource.  (Yes, the same Tracy I mentioned in the natural plastering post.)

Our building site is perched on the top of a bedrock slope facing due south, but with a longer east/west side, so while we have full sun all year, we also need lots of insulation to capture the rays with as much passive solar practices as possible.  The rectangular shape of the space available between the outcrops of rock made the use of bales easy to apply.  The bales provide infill walls only, as we designed the timber frame structure to hold the weight of the roof, which extends out with a 2 and a half foot overhang on all sides to keep our rainy climate away from the walls.  All the strawbales came from Mitchell’s, a family owned farm on the Saanich Peninsula.  They had an excess of barley bales that year, and as we inquired about 700 bales needed for our house as well as for a workshop that our friends were building at the same time, they were happy to help with a reduced cost and extra arms loading them into the moving truck that we rented to move them over to the island.  We used the structure of our roof and timber frame as a place to stack all the bales together while we worked on a few things that needed to be in place before the bales went into the walls.

We constructed the toe-ups for the bales- a step of sorts that the bales sit on.  This is a path of 2×4 lumber on it’s side, bolted into the foundation, and filled with drain rock.  We heard of people using crushed glass (from recycling depot), or corks (lots of trips to the recycling depot!) or anything that provides fill with air gaps.  We also used these toe-ups as a course for our electrical wiring, running the wires inside the lumber then up to our electrical outlets that were posted at the required height up from the 2×4, and being essentially free standing from the bales.  We protected the wires from the drain rock with a small piece of rigid foam insulation.  We did this for a few reasons, the main reason being that the electrical inspector wanted to see the rough wiring before the bales potentially hid them from view, and we didn’t want to get partway through our wall stacking then have to wait for him to make his visit, which can be the case if wires are run between bales.  We also wanted to run the wires up the backs of the timber frame to the places that would need wiring up high.  We stapled strips of burlap all along the places where the bales would come up next to wood, and a strip of building paper on the outside of the burlap.  This was more for the plastering stage, but it was essential to do it before the bales went into place.   We then posted bamboo poles on one side of the toe-ups up to the height of the top beam.  This was to be a part of our exterior pining system.  After the bales were in, we placed bamboo poles on the other side then sewed them together with a giant needle and baling twine through the bales, inside to outside.  We also put in place all the window bucks, securing them to the timber frame and the toe-ups so that they would not shift with any settling of the bales.  This created more detailing of the bales around the framing, but we had heard stories of frames shifting out of square and plaster cracking, so we decided to go with the rigid framing to avoid potential problems.

Finally we started building the walls, and with lots of eager hands!  Many of our friends had asked to come and take part, so we invited anyone who wanted to help.  We had a rotation of 4 or 5 people everyday for the week that it took to fill in the walls.  Although it was now november, we had a beautifully dry and sunny week to work in.  We learned how to reshape the bales to fit smaller spaces, either with a small electric chainsaw, or by splitting them and retying them with that giant needle.  We used zip-ties to tie the bales together end to end through the baling twine, and the fact that the twine on the bales was so tight it was hard to slip a zip-tie under them was a good sign that these tightly baled bales would be good insulation and might not settle too much.

We were even able to incorporate the enthusiastic pleas of our little ones, giving them lots of jobs with the small bales we created for the small spaces, and with the continual cleanup of loose straw everywhere.  They mostly settled into playing on the constantly diminishing pile of bales, but it was with great satisfaction that I could say that our building materials double as a healthy play fort.  I was also grateful for our decision when I spotted flocks of chickadees foraging through the litter for seeds and nest building material.  I loved finding the occasional sprig of dried wild chamomile bundled up into our walls, adding an element of calm to the energy of the house.

The last job was trimming.    Colin used a grinder and gave every inch, inside and out, a careful haircut to get a smoother surface on which to plaster.  Then we did a bunch of stuffing- making little twists of straw and shoving them into any little cracks that are created between the bales or around the window framing.

I am really grateful for the process we went through that arrived at the decision to build with strawbales for this house.  It has been a satisfying experience all along, from the many people that walked in and smiled with memories of family barns in their childhoods, or the soft cushiony sound of the acoustics as we played music perched on bales as benches, or knowing that any excess will go onto my garden paths or as summer mulch.  It is a building material that fits beautifully into the harmony of natural world, and creates those wide, adoring window sills that frame such glorious views of the world we honour and respect. 

Natural Plaster

A large part of the strawbale construction of our house is the natural plaster system that closes in the bales while still allowing a flow of air to pass through, supporting a breathable wall system that is totally weather proof.  I am not going to pretend that I can write a whole how-to guide here on this post, but instead I hope to give a most complete account of what we did to our walls, and hope that it is helpful to anyone interested in taking on natural plastering, or it is interesting to anyone just curious.  There are many books, websites, people of knowledge, and workshops out there that can give accurate (and sometimes conflicting)  information, and we have taken these steps available to us for what makes sense for our situation.

We have been blessed to have with us in our community an experienced natural builder and good friend, Tracy Calvert.  She has been integral in directing our experience, and helping out with the attaining of supplies and tools.  She is especially experienced in the art of natural plaster and it’s many layers of applications.  Our first layer was covering the straw bales with  clay slip, which is essentially like splattering the straw with thick chocolate milk.  Messy.  We obtained the clay from a pottery studio on Mayne Island, it is the off cut pieces from the creations of the studio which were destined to be sent to the landfill.  Some studios take the effort to reconstitute these wastes back into usable clay, but it is an arduous task to reproduce good quality clay.  Many studios prefer to consider these bits unusable, and so having them picked up by natural plasterers is a positive move for everyone.  After soaking the clay, we mixed it up with a heavy duty paint mixer mounted on a drill, until it was thick and smooth.  My method for getting it on the walls was to splash it on with one hand, holding a bucket below to capture what didn’t stick while rubbing it into the fibre of the straw.  Whatever technique is used to get the slip on the wall is a good one, there really isn’t any wrong way.  I covered every visible straw bit of the house, inside and out, turning it a lovely shade of dark reddish-pink.  It then spent a whole winter like this.

Layer number two is a cob mixture of clay, sand and straw mixed up in batches by foot and pushed on the walls by hand.  We got local clay from a farm down the road who was excavating a pond, pit-run sand from a local quarry, and the shavings of straw from when we trimmed the bales to make the surface even.  A good test for determining the quality of the clay is to do a jar test- put some clay in a jar with water and shake it up, then let it settle.  This will show the ratio of silt to clay, and whether or not there may be too much silt in the clay.  Ideally, the less silt, the better.  We built a soaker pit from leftover bales draped with a solid tarp, and kept it filled with softened clay ready for using.  After spraying the walls to get the slip wet, we pushed on the layer of plaster, spreading it about a half inch thick.  We started in early spring with a birthday party for our 4 year old, inviting all his friends and their families- really, this layer isn’t very difficult to master and it’s lots of fun to do with friends.  I had home school plaster parties, ladies’ night plaster parties, and afternoons with a few friends and their kids playing nearby.  The inside and out was finally done by the fall.

I was able to get started on the third layer in April.  Tracy came for a morning and went over the variation of the cob mix- this time the ratio of clay to sand was 1:2, with one and a half buckets of finely sifted straw.  (I used a certain bucket for measuring, and went through a few mixes of experimenting with ratios before finally getting to the mix that cracked the least.)  The sand we used was a finer, washed sand.  This layer is applied with a trowel, and encompasses the task of sealing in the flaps of burlap that connect the bale walls to the timber frame.  (Since clay doesn’t stick to wood very well and shrinks when it dries, a strip of burlap was stapled to the backs of the places where straw meets wood, and so the clay doesn’t move away from the wood when it dries.)  The burlap has to be rightly stuck down, so we brushed it with more clay slip until it was nicely saturated, then we rubbed it in roughly with plaster before applying a smoothly troweled layer of plaster.

We also took the time in this layer to shape those beautiful big curves of our windows, sometimes building up the flares with extra plaster until the shape of the curve was formed to our liking.  This is also the layer into which any sculptural work can be done, which we all know is the best part of natural plaster and cob. Nana enjoyed contributing her artistic sculptural skills around the house.

I was much more careful about who I invited to help with this layer- I mostly took it on myself (although Taeven and Cedar both took on their own ways of plastering with the trowel so they could help out).  I had the help of a few friends who are artists (good hand-eye co-ordination) and who helped with the previous layer, so they had an idea of what the result was to be and they came many times to help, building up their experience of working with the plaster.  My own abilities changed so much with this layer as I worked around the house, that I have re-plastered much of the first area I started on, seeing flat spots on window curves and too much cracking in other places.

We also covered some of our interior walls with plaster.  In the mud room, we built a stud frame wall, then stapled expanded metal lath to the sides, filling in the middle with straw.  The plaster goes straight on the metal, in two layers to avoid any movement of the mesh beneath.

The final layer of plaster is yet to be applied, and will undoubtedly require a whole new lesson in natural plaster.  The outside will be a mix of lime, sand, and colour pigment, the inside coat uses finely powdered cayolin clay as its base.  We fine-tune the quality of our trowels with Japanese trowels.  There is more technique involved in applying the plaster to avoid lines showing up…  I am looking forwards to working with Tracy again to learn this new skill level of natural plastering.  The journey of using natural plaster on our walls has been long and enjoyable, I have massaged every inch of our house with friends, conversation, children, family, quiet musings, music, meditation, in the sun and the rain.  I have mixed every batch of plaster with the energy of my feet and legs, and with the soles of friends.

 

The Living Roof

The gently curving south side of the roof was designed to be covered in a carpet of succulents.  We had  the size and structure of the timber frame approved by our engineer to hold the weight of six inches of soil, plus a calculated weight for snow and water.  We were inspired by other green roofs we had seen, and by numerous pictures in natural building books, and by the relative easiness of the construction of layers required.  We also liked the idea of our roof being an absorbing entity, making use of the sun and rain that tumbles down from the sky onto every surface area.  The decision to use succulents came from the idea that we wanted the coverage to be drought tolerant and spreading easily to avoid too many weeding sessions.  We also saw that the rocks upon which our house was going to be built were covered already with the native stonecrop, so I lifted them in their clumps and put them aside until I could finally plant them into the soil of the roof.

On top of the rafters, we put  down plywood and building paper as in the construction of a regular roof, but on that we rolled out a rubber pond liner out to a built up lip that went all the way around the outside.  Then, we put out a call for old carpets, to act as a drain mat and protector from roots wiggling down.  It was important to use the kind of carpets that had a burlap or jute backing, instead of the rubber backing, as we wanted to make sure that water could drain through it and towards the edges.  We lay down some drain rock around perforated pipes along the side lengths to allow water to collect and flow into the down spouts.

We did a final layer of landscape cloth before we began to bring up the soil.  With a pile of local pit run sand, a pile of soil that was excavated earlier when we dug out our pond, and the help of many many friends who came out for a work party on a fine June day, we managed to fill the roof with 4 inches of soil one bucket at a time.

It was a fabulous day, we had lots of enthusiastic shovellers, diggers, bucket haulers, pulley operators, dumpers, and rakers.  Families came and took turns relaxing and swimming in the pond.  We had lunch for everyone, and cake later on to celebrate Cedar’s 5th birthday.  (Last year we had a plastering party for his birthday- imagine a bunch of kids with buckets of clay plaster and a green light for slopping it all over a bunch of bales…)

Workparties are a definite for natural building, providing the task at hand is fairly easy to monitor.  It would have taken Colin and I a month of hauling buckets up there… and we did it in one day and provided lots of community members the chance to participate in an aspect of natural building which is fun, positive, and an example of creating healthy environments.  We are so glad that we have such a supportive community of people who share our values and visions of a vibrant earth, and who in turn have skills for us to learn from.

So then we started putting the plants in, some that I had began propagating over 2 years ago.  Hens and chicks, sedums, and echverias, plus all the stonecrop from the rocks that are now buried under the house.  Taeven and Cedar were excited to help, and we came up with the idea to plant the stonecrop in a big infinity symbol along the center spine of the roof, with the darker green hens and chicks inside the loops, and the burgundy sedums around the outside.  It will be interesting to see the shapes that we created with the different colours of the plants as they get established and fill out, sending their tall stalks of flowers out at various times of the year.

Right now, it is a weedy mess.  It is yet another task on my list of fall jobs- weed roof.  I am sure that a few weeding sessions will be needed until the seeds that were in the soil will have all sprouted, and until the carpet of succulents fills in the spaces.  So far it is functioning well, and catches my eyes softly as I move around the property.  There is beginning to be lots of information out there on the construction of living roofs as well as their benefits, and I encourage anyone to try it out as a retro fit or as an option for a new building.  One thing we did discover… there is lots of ready made, manufactured products being offered and promoted, usually at very high prices.  Our research indicated that all we really need is already around us in the form of recycling!  (Pond liner exempted, you really don’t want any leaks in a living roof).  The creative possibilities are endless, and open to any situation.

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