Posts Tagged ‘green construction methods’

A Tour of the First “Passive House Certified” Residence in Canada

March 8th, 2011

First Certified Passive House Residence in Canada

We went to Ottawa for Family Day weekend to visit my husband’s family. A few weeks before this, I received a press notice that an Ottawa house had become the first Passive House certified in Canada. “Say,” I thought, “wouldn’t it be great if I could arrange for a tour of the house while I was in Ottawa?” So I did.

If you’re not familiar with the Passive House movement, houses are designed and built so that they only use 15 kwh/m2 of energy for heating and cooling and 120 kwh of electricity per month for lighting, appliances and other household uses. To give you an idea of what this means, the typical new home built in Ontario today uses about 10 times the amount of energy consumed by a Passive House certified building. If you’d like to know more about the Passive House movement in Canada, you can read about it here.

Chris Stratka of Vert Design was intent on building a super-insulated home when he bought the property in the New Edinburgh neighbourhood of Ottawa. However, when he took the design to a Passive House consultant he was told it probably wouldn’t qualify because the building materials and systems available in Canada that he had specified were seen by the consultant as inferior to those available in Europe. Although Chris was disappointed, he decided that he’d build the “best” house possible and leave it at that. Specifically, Chris is aiming for a Platinum LEED for Homes rating, with a particular emphasis on the Energy and Atmosphere section of the certification.

Chris decided that the best way to achieve his home’s performance targets was to use a modular home builder, and located one just outside Ottawa who would build to his insulation specifications. As I’ve written about before, modular home building has several environmental advantages such as the materials being protected from the elements (moisture, heat, cold, etc.), less waste in production, and less disruption to the local neighbourhood because the final product is put up so much faster. Chris’ home was assembled on site in three weeks. Yes, there was still the need for electricians, HVAC installers etc., but the major construction vehicles were on the street for a short period of time and there was never a dumpster on site.

Once the walls were assembled, insulation was added to the ceiling, caulking and sealing was done, Chris called in green building specialist, Ross Elliott from Homesol Building Solutions, a building performance consulting company that provides third-party inspection, testing and verification services. Ross performed the blower door test to identify any leaks that might have escaped the caulking and sealing. Chris said that if you’re going for energy efficiency in a new or renovated home, it’s essential to bring in the energy auditor a few times while the house is under construction. It’s much easier to fix leaks and holes in a partially built home than once the drywall is up and everything is already in place, and it will save you money in the long-run through lower energy bills. It was after the initial test that Chris and Ross believed that they just might be able to qualify for Passive House certification after all.

There are two other aspects about the house that were of primary importance to Chris:

1. He built it using only North American supplied materials in order to demonstrate that we North Americans have the resources and the technology to build super-insulated homes. All the major building materials,  hot water heaters, geothermal heating/cooling, and windows are manufactured in Canada and the US.

2. Testing for air leaks at several stages of building was essential to achieving the home’s air tightness.

In order to build a Passive House certified residence, there are several elements in addition to air-tightness that are essential to take into consideration:

 

Inline Fiberglass Windows

Orientation: Part of the Passive House formula is the ability to take advantage of the free heat a house can receive in the winter by orienting windows to absorb the light. In this case the house if perfectly situated, facing due south, and backs onto conservation land next to the river. It means he’ll never have to worry about another building going up that would eventually block his sunlight and heat source. The canopy in place protects the room from the heat in the summer when the sun is high in the sky.  The shading system that is currently being installed protects the rooms from the heat of the low winter sun.  In this building the issue is not getting enough heat – it is getting too much!

"Tilt" feature of "Tilt and Turn" windows

Windows: All windows are “tilt and turn” windows provided byInline Fiberglass, a window manufacturer based in Toronto, ON. They are triple-glazed, Low emissivity, argon gas filled, and the fiberglass frames themselves are insulated. The day I visited it was -15, but when I put my hand to the window pane, the glass was warm. When I do the same thing on my own home’s windows, the glass is always chilly; in fact, it’s just plain cold anywhere around any window in our house.

A nifty feature of the windows is the “tilt and turn” aspect. They tilt open at the top to let air flow in or out, or can be opened completely as a door on side hinges. This is a great feature to quickly cool down a room in the summer time, if the hot air has risen to the third floor.

Heating and Cooling System: In hindsight, Chris says, the geothermal heating and cooling system he had installed wasn’t necessary. However, when first designing the place, and being told that it would never pass Passive House certification, he figured he’d use the least intrusive HVAC system he knew of — geothermal. His particular system is made by Maritime Georthermal from New Brunswick. In future passive house designs, he would use baseboard heating in each room as Passive House homes are designed so that traditional heating methods such as central furnaces, aren’t necessary. He’s also added a Heat Recovery Ventilator (HRV), from Airia Brands from London, ON. When I asked him why he hadn’t chosen an Energy Recovery Ventilator (ERV), he replied that ERVs are more suited to humid climates where moisture is present year round.

For a complete breakdown of the specifications of the wall composition and HVAC, hotwater and windows used, please see Chris’ PDF document on his website.

Other “eco features.” Passive House certification’s focus is on energy use for heating, cooling and plug load. It does not look at other factors such as indoor air quality, water use, or minimizing the use of building materials. Chris referred to LEED criteria for these areas. Some of the more eco-friendly features of his house are:

  • Green Roof garden. Essentially his house takes up the entire plot of land, with only a small patch of property out back. Since he would like to grow some of his own food, he has designed the roof so that it can hold a substantial garden with herbs, tomatoes, beans and other vine plants, and maybe some crooked carrots (the depth of the soil will be about a foot). The green roof will also add further insulation to the home.
  • Rainwater recycling. There is a space built into the second floor that is awaiting rain barrels which will capture run-off from the eavestroughs and will be stored inside the home to feed toilets with water. The point of putting the rain barrels on the second floor is that the water is fed to the toilets through the use of gravity. That way they are unaffected if the electricity goes off.
  • Energy Star Appliances. All appliances, including washer/dryer, are Energy Star rated. The cooktop by Kenmore, uses induction heating, which is also quicker than gas.
  • No gas line to the house. Chris says that there are two reasons he relies on electricity for heating and cooling, cooking and hotwater: the first is that gas doesn’t fully combust and is not indoor air quality friendly, and secondly, to become dependent on gas means that you can never convert your home to 100% renewable electricity. Chris has plans for solar panels on the roof.

For more information on this project, visit VertDesign.ca

For more information on Passive House certification, visit the Passive House Institute US.

In Canada see: Passive Buildings, and Canadian Passive House Institute.

Fischer SIPS — Superior Insulation, FSC OSB also Available

January 7th, 2011

Fischer SIPS being installed

Fischer SIPS contacted me regarding their company’s SIPS panels. I’ve written about SIPS before and their benefit for any building project.

Fischer SIPS have an added benefit of specifying SIPS with FSC certified wood.

If you’re not familiar with SIPS, they are “structurally insulated panels” used for building homes and commercial structures and are an “all-in-one” product providing the framework and insulation for a project at the same time. SIPS are a made as a “sandwich” of Oriented Strand Board (OSB), insulation, and OSB. SIPS are available in varying dimensions with varying projected R-values. The benefits of using SIPS in a building project are numerous.

  • Energy efficiency is significant. According to the Fischer website, SIPS’ actual R-value (ie., the number they’re given based on their thickness), and their performance R-value are significantly different, with the latter being higher than the performance R-value. This statistic is unusual because, generally speaking, R-values will be the same or lower than “performance R-value” due to other factors (construction methods, thermal bridging, etc.). Further, air tightness is superior to a stick-frame built home because the SIPS are fully insulated and there are fewer thermal bridges (where heat can transfer from warmer to cooler areas). Heating bills are significantly lower than a traditional stick-frame and fibreglass insulated home.
  • Less waste on site. Building a house is one of the highest waste producing activities around. Using SIPS that are constructed in a factory significantly cuts down on waste on the building site. Within the manufacturing facility, excess insulation (in this case expanded polystyrene — EPS) from SIPS production can be reused for other EPS uses.
  • Use of rapidly renewable resources. OSB is made from small, rapidly growing trees not suitable for other uses. A full 85-90% of the tree can be used to make OSBs.
  • Speed of Constructing a home. SIPS can be assembled in up to 30% less time than a stick-framed house (although a crane is necessary for the roofing panels) because the frame and insulation are all in one.
  • SIPS are ideal for cathedral ceilings because of the insulation already in the panels.
  • Fischer SIPS are available with FSC certified OSB (in 4’x8′ and 4×12′ dimensions only).

Fischer ships its products across the United States and Canada and as far away as Russia.

For more information, visit the Fischer website.

FischerSIPS®, LLC
1800 Northwestern Pkwy – Louisville, Kentucky 40203
Phone:  800.792.SIPS       (7477)
Fax: 502.778.0508

An Interview with Sylvia Cook, Rammed Earth Builder

October 28th, 2010

Completed Rammed Earth Walls. Awaiting doors, windows and roof.

On a clear, sunny day in mid-October, I accompanied Terrell Wong, of Stone’s Throw Design, to beautiful Northumberland County to meet Sylvia Cook. Sylvia was building a rammed earth home and Terrell was the architect. I was intrigued by the idea of a rammed earth home and as I’ve mentioned in a previous post, it’s a lot different looking than I thought it would be. I’ve described the building and the technique in that post, but I was also interested in what made Sylvia decide to build such a remarkable dwelling in the first place.  I asked Sylvia a few questions about her motivation and what the future holds, below are her answers:

1. What were the factors or influences that led you to want to build a sustainable house? And, what helped you to determine that rammed earth would be the most sustainable material?

Sylvia: Some years ago I had the pleasure of hearing Gywnne Dyer speak and found myself in agreement with his assessment that the biggest threat to global security had little to do with terrorism or even traditional wars, but everything to do with climate change.  He provided convincing evidence that climate change would kill millions of people, impoverish hundreds of millions more, disrupt cultures, foster terrorism and cause wars.  And all we really need to do to prevent this is eliminate our dependency on fossil fuels, something we will have to do sooner or later in any case as the supply is limited.

I’ve been interested in sustainability long before the phrase had been coined.  I believe it was “caring about the environment” back in my day, but I like the concept of sustainability, defined as what it will take to sustain the planet in such a manner that humans can live on it in comfort.  It had long been my hobby to research and design the most sustainable house possible, and I had looked into straw bale, log homes, earthships, cob, adobe, ICF, glass bottles, geodesic domes, and a number of concepts using recycled materials. When I came upon rammed earth, I realized it met all of the criteria I had come to associate with sustainability:

  • locally available, abundant material – appropriate subsoil is found everywhere, a very small (five acre) pit would provide enough leftover material (after the gravel had been extracted) to build 5000 homes
  • does not deplete any natural resources – we currently clearcut over a million acres every year in North America to build houses.  Even strawbale depletes the topsoil.
  • non-toxic – there is nothing organic in rammed earth hence nothing for moulds to grow on and no need for chemicals to combat moulds or fungi in the building materials.  Nor are there any other chemicals needed: no paints, drywall compounds or plastics.
  • beautiful in its unfinished state – if a building is not beautiful, no on will want to live in it and every added step of finishing requires more energy to process, transport and apply.
  • durable – rammed earth has stood the test of time: the Great Wall of China is only one of many ancient examples from all over the world.  Modern rammed earth, stabilized with rebar and a small percentage of cement, should easily last hundreds of years, eliminating the stream of waste as houses need repair and replacement.  Stabilized rammed earth is impervious to fire and able to withstand hurricanes, floods and earthquakes.
  • energy efficient – the most important aspect in my view.  In the occupancy stage, representing the vast majority of a building’s energy use, rammed earth truly shines.  The enormous thermal mass of the walls allows them to absorb and retain solar energy from south facing windows.  The house will literally heat itself and, if properly insulated, will stay warm.  In the summer a large overhang ensures that the walls stay cool.  Add a few solar panels and the house is net zero energy, for every one of its five hundred plus years.  If every house on the planet were built of rammed earth we could cut our fossil fuel use in half.
  • feeds the human spirit – there’s something about rammed earth that makes it very calming.  Perhaps it is the solidity of the 18” walls, the natural surface, the quiet of the building, or some less definable quality.  If architecture is going to improve the human condition, rammed earth is an excellent starting point.

First and second floor, pre floor installation

2. How important is thermal mass of a building in your decision?

Sylvia: When designing a passive solar house (which is a house heated by the sun shining through the windows) the challenge is always to store the energy.  Any house will warm up when it’s sunny, usually too much, but cools down quickly when the sun is gone.  Older heat storage solutions included concrete floors, Trombe walls (a thick wall just inside the south windows, blocking the view), rocks, water (in pools or bottles in various locations), underground tunnels, etc.  Rammed earth walls give ample thermal mass acting as a huge heat sink.  A typical stick frame house has one or two tonnes of mass; 50 – 100 tonnes is considered the minimum necessary for heat storage.  In our construction the 6” of insulation in the middle of the wall leaves 6” of rammed earth in the interior of the house, plus the two 18” uninsulated interior walls, yielding 530 tonnes of thermal mass.

3. How labour intensive is it to build a rammed earth wall?

Sylvia: It is certainly more labour intensive to build rammed earth than standard building methods.  The majority of the cost of building rammed earth is labour; the material is “dirt cheap.”  But why is this a bad thing?  Is it preferable to spend money on toxic, energy intensive, highly processed materials or to provide a living to a group of generally young people interested in making a difference in the world?

The lines represent different layers of earth

Natural waves in the walls due to the layering of the dirt mixture

4. What will be your primary heating source?

Sylvia: The sun.  (See #2.) The Ontario Building Code insists on some form of heating so we’re installing baseboard heaters as the cheapest alternative but expect that they’ll almost never be turned on.  We investigated geothermal and various in-floor systems but just couldn’t justify the expense for the small amount of heat needed.

5. How do you install the second floor, which from the photos, doesn’t exist yet?

Sylvia: There will be ledger boards anchored to the walls with epoxied-in threaded rod.  The joists will hang from the ledger boards, just like building a deck.  I’ll send pictures of the process if you’re interested.

6. You have a lot of window space in the design. How are you dealing with the contradictory goals of maintaining a constant comfortable temperature within the house, while allowing for natural light? In other words: most windows are the weak points of a home’s thermal envelope — why do you feel they won’t be a significant issue affecting your home’s interior temperature?

Sylvia: If you look at the net heat gains and losses from windows, south facing windows represent an overall heat gain, north-facing windows are a heat loss while east and west are neutral.  Terrell Wong’s brilliant concept has allowed us to create the perfect solar (that is, south-facing) house that completely fits the naturally east facing slope. There are no north-facing windows. Our windows are also exceptionally good: Alphawin windows come from Germany with the Passiv Haus standard.  You should talk to Terrell about the windows.

Composition of 18" thick walls

7. Can you talk a little bit about your business goals? Is your house the first in a series of rammed earth buildings?

Sylvia: Several years ago I retired from teaching to take on the project of building a sustainable house.  I knew I wanted rammed earth but the highly technical nature of the process, from soil selection to forming systems and tamping techniques, seemed somewhat daunting.  I also realized that my original concept of building one house as an example of what could be done was not as important as offering a genuine alternative in an attempt to change the built environment.  To that end I incorporated aerecura sustainable builders and enlisted the help of an experienced rammed earth builder to construct the rammed earth garage as the first part of a steep learning curve leading toward the goal of a rammed earth industry in Ontario.  Long before we put a shovel in the ground, and with no advertising effort on my part, I have received emails and phone calls from people interested in rammed earth.  People are drawn to rammed earth for many reasons.  Some, like myself, are attracted to the sustainability of rammed earth.  Others, including many architects, are entranced by the natural beauty of the material as well as the creativity afforded in designing with rammed earth.  Still others are seeking the health benefits of a building system with no toxic materials and no organic matter, thus nothing for moulds, insects or other pests to eat or burrow into.  One family approached me after losing their house to fire; rammed earth is rated as non-combustible, another benefit of using only inorganic materials.  My husband was entranced at the possibility of a fabulous music studio, using the superior acoustic properties of rammed earth.  I have been contacted by people in Saskatchewan, Manitoba, Quebec and Nova Scotia, though aerecura’s initial business plan will keep us in southern Ontario.    aerecura sustainable builders believes that rammed earth has the potential for widespread mainstream acceptance in both the residential and commercial realms.

For more information on rammed earth buildings, please contact Sylvia Cook at sylvia@aerecura.ca

A Massachusetts Garage made from easily accessible materials: Tires and Dirt

July 12th, 2010

Elizabeth Rose

A few months ago I wrote a piece about an organization, Long Way Home, that is building a school in Guatemala made out of tires, plastic bottles and dirt. This is a great project that involves the local community, local building materials an enthusiastic group of volunteers. Elizabeth Rose is the president of the Board of Directors of Long Way Home and she has decided to use the same techniques to build her garage. Her mission is to build the first tire and dirt building in Massachusetts.

The theory behind using tires and dirt is based on architect Michael Reynolds’ philosophy of using local, indigenous materials that are plentiful, easy to use and involve more labour than energy consumption. Elizabeth covers more of his reasoning and her goals of sticking to his philosophy in her own structure on her blog.

Tires and dirt, if used properly, can provide a thermal mass that can measure up to R50. It would depend on the diameter of the tire, as well as the type of dirt used and how compacted the fill was, but here in Ontario an insulation value of  R50 is over twice as much as standard building code requires! Pretty amazing.  The corollary of that is that you have to have the space to build a structure like this because these walls are thick! As thick as the diameter of the tires plus the interior and exterior finished coat.

Packing Dirt into Tires

Elizabeth has started a blog that keeps track of the progress of building this garage.  It’s always a challenge being a pioneer in any field, and using worn out tires and dirt is no exception. So far there have been a few errors in tire measurement and dirt selection, but what’s interesting is to read is how Elizabeth resolves mistakes, tracks down suppliers and how her architect, builder and soil engineer decide what kind of dirt will work for filling the tires. Elizabeth has discovered a few things on her journey to build a unique, “green” garage, such as:

  • there is only one tire recycler in Massachusetts, JP Routhier and Sons in Littleton, MA.
  • a supposedly “environmentally friendly” aggregrate (dirt and stone quarry) company, Aggregate Industries, with more than just a little dirt under its proverbial carpet (including a $2.75 million fine from the EPA for improper storm water management) and,
  • how physically exhausting, but rewarding, it can be to build your own rammed earth building.

You can follow Elizabeth’s progress on her garage at her blog: http://lizyrose.wordpress.com/

For more information on Michael Reynolds’ company, see http://earthship.com/

Building Homes in Guatemala With Garbage

February 19th, 2010

Elizabeth Rose, President of the Board of Directors of an organization called “Long Way Home,” contacted me to tell me about a very unique project that’s underway near Comalapa, in the western highlands of Guatemala. While building houses and schools in developing countries by non-profit organizations isn’t new, what is different is that Long Way Home uses local materials. In this case “local” materials consist of dirt from the property where they are building combined with old, worn tires and plastic bottles bound for landfill or empty fields.

To use materials such as plastic drinking bottles and old tires as building materials is nothing short of brilliant for many reasons. These waste materials are found in abundance in Latin America, while recycling or proper disposal methods are severely lacking.  Garbage is a real problem in most developing countries; governments can’t provide the infrastructure to deal with it so villages tend to either burn it which lets noxious fumes into the air, or leave it  which then pollutes local watersheds and lands.

Currently, Long Way Home is building its biggest project to date: a school and community center and park with a community garden, basketball court, soccer field and community kitchen. The project takes into account the slope of the natural landscape, incorporates solar energy panels, a waterless composting toilet and rainwater capturing systems into its design while educating the community on the importance of a clean environment to human health.

Schematics of Community Project

The schematics of the new community buildings show how the buildings will use natural ventilation to keep the building cool in summer, the walls being as thick as the tires’ diameter and packed with dirt have a significant thermal mass to them. This means that the walls are able to keep heat out in the summer and in in the winter. Ventilation in the upper tier of the behive-shaped structure allows heat to escape during the day, and cold air to filter in at night. The tires and pop bottles form the basic structure of the wall and are covered with a cob layer (pine needles mixed with mud) and then finished with local lime stucco that dries into a smooth white plaster appearance. Best of all, the work is all low-tech with little maintenance required which means the buildings will provide shelter and education for years to come.

The latrine is made from old pop bottles that have been filled with non-perishable garbage for density and mass. The bottles are bound by chicken wire and then stuccoed, creating a very ingenious latrine (not to mention a good way to get rid of garbage!).

Plastic bottle latrine during construction

To follow the progress of the building, you can link to the blog written by the architect, Ericka Temple, for the project here:

http://catorcekt.wordpress.com/

For more information on Long Way Home’s mission and their progress, visit their website.

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