Posts Tagged ‘Living Building Challenge’

LEED for Homes and Other Green Housing Certifications

April 3rd, 2012

In 2007 we moved into a brand new house with the naive view that new was always better than old. My husband’s and my belief was that a new house would involve less maintenance, lower running costs, higher energy efficiency and overall fewer headaches. What happened over the course of the four years that we lived in that house was that I began to realize that new isn’t always better than old, particularly when you’re buying a builder’s home on spec as we did. While we did have lower running costs than in the previous house, a lot of it was due to the more efficient appliances, and slightly better insulation. We had more issues in this house in the first 3 years than we’d had in our two other previous 60+ year old homes. By the time we moved out four years later, I had come to a different conclusion: if I were to buy a new house again — and that was a big IF — I would only buy one that had been certified preferably LEED certified and preferably Platinum.

I’m not saying there aren’t excellent builders out there who go above and beyond their duty, making sure a new home will withstand the myriad of weather it’s exposed to — but there are also builders who will build to minimum code or less, and take shortcuts because not all shortcuts will be caught by building inspectors. Case in point: down the street from our house was another one going up by a different builder who didn’t bother to put tar paper down before adding the roof shingles. Will the building inspector find that? Only if he climbs up a ladder and lifts a shingle. Inaccessible areas such as behind walls, difficult to reach roofs, etc., hide a lot — there are many a poor electrical wiring jobs out there that are concealed behind walls (as we found out), many shoddy dry-walling jobs (as we found out), and some homes that are built before receiving the city’s approval for the water drainage system….as we also found out (sigh). We were fortunate because most of these things were fixed over time after a lot of threats, heated phone calls and emails, but I’ve also heard of cases where homeowners are out of luck — especially after the Tarion Warranty runs out.

I know there are builders out there who complain about the extra paper work and activity involved in certifying a home, and I understand, but I can also tell you that a certified home forces a builder to do it right, to not cut corners and to identify any mistakes before the walls are up and critical parts are covered. It likely saves a builder work in the long run. Maintenance costs tend to be lower and call backs from owners are much rarer. So really, if everyone puts the time, effort and money up front, it saves money, time and effort down the road and gives the buyer reassurance in the long-run.

Having said that, there are a lot of green building certifications out there from the ones we’ve all heard about like R-2000 to the lesser known ones like the Living Building Challenge. I thought I’d put a list of green building certifications available for homes and the priorities on which they focus. That way, if you’re looking for a new home, you can be sure to ask the builder which one of these his/her building company follows. If a builder doesn’t use any certification it doesn’t mean they aren’t building well, they may prefer to put their time and money into the structure instead of the paperwork. Ask for the names of former customers and check with them as to whether they’re satisfied with the end result. Doing your research up front may save you a lot of headaches down the road.

R-2000: The energy crisis in the 1970s prompted a re-examination of our previously cheap supply of fossil fuels. At that time a project by the Saskatchewan government featuring an energy efficient home was translated into a nationwide program by the Canadian government, called R-2000. Certain energy efficiency standards need to be met in order to qualify to be certified as an R-2000 home. All builders receive training and certification in order to build R-2000 homes. The criteria for an R-2000 home are revamped as new building techniques and technologies become available but the standard incorporates the latest in energy efficiency, building techniques and standards available.

The focus of the R-2000 home certification is about reaching a high level of energy efficiency through tight building envelopes. A qualifying home must pass a blower door test after it’s built by an independent R-2000 certifier and achieve at least a rating of 1.5 ACH (air changes per hour) at a pressure of 50 pascals depressurization. Further, it must address issues with indoor air quality such as even ventilation, circulation, moisture and air distribution throughout the house (however, there is no mention of off-gassing from adhesives, paints, stains, and other materials used in construction). The homes also contain such features as water conserving fixtures and building materials with recycled content. There also isn’t any mention of location as being an important factor in the home’s construction. In some of the other certifications, using previously used land, as well as land with easy access to shops, services and public transportation holds equal weight to how a home is constructed.

R-2000 homes are easier to find than some of the other certifications across Canada.  Homes are verified by certified R-2000 building inspectors during the building process. While a conventionally built home emits approximately  5 tonnes of CO2 emissions yearly, an R-2000 home emits 30% less than that.

The Office of Energy and Efficiency of the Government of Canada provides a search page to find R-2000 home builders in every province.

For more information on R-2000 homes, see this page.

EnerGuide Rating System: This certification system is strictly about measuring your home’s energy performance using a scale rating of 1-100.  Most older homes measure between 65-72. A conventional new home with no energy efficient upgrades measures 73-79, New homes with some energy efficiency features measure 80-90, while a home with little to no extra energy needs measures 91-100. A score of 80 or more is excellent.

An Energy auditor measures your home’s EnerGuide rating and the work can be performed on any home, built or not yet built. When constructing a new home, an energy auditor should be brought in early in the process as he/she can run the proposed design through energy modelling software to see how the proposed home should rate once constructed. He can also make suggestions about how to increase the home’s energy efficiency.

Energy Star Certified Homes: This certification is entirely about energy efficiency. The bottom line is that a home must score at least 80 on the EnerGuide scale in order to qualify. Other requirements are that, depending on where the home is located, it have between 2-2.5 air changes per hour at 50 pascals depressurization. Note that this is one half to one air changes more than an R-2000 home, meaning it is not quite as energy efficient as an R-2000 home (fewer air changes mean less air is leaking in and out of the home). Energy Star certified homes also need to be certified by an independent energy auditor who will do inspections while the home is being built in addition to the one final blower door test after the home is built. A new home will also contain Energy Star rated appliances and light fixtures. Basements will be insulated to the same degree as attic spaces. There is no requirement for the type of materials used or location of the home vis a vis services, amenities or public transportation.

For more information on Energy Star home requirements, see this information package.

LEED (Leadership in Energy and Environmental Design) for Homes:The United States Green Building Council was established in 1998 with the intention of developing a system to encourage the building industry to build better buildings. The development and operating of buildings uses up to 40% of all energy consumed in North America, so reducing buildings’ energy demands is in everyone’s best interest. With that in mind, the USGBC developed the Leadership in Energy and Environmental Design designation — a standard which first came on the scene as a pilot project in 2000. In 2003 the Canada Green Building Council introduced a version of LEED more suited to the Canadian climate. The program has since undergone two revisions in the US and one in Canada. It is a constantly changing certification, as it should be, to both keep up with changes in technology and building techniques.

LEED is a more encompassing designation than either Energy Star or even R-2000 and it is available for every kind of building from large renovations of existing buildings to new buildings and homes, and now neighbourhoods. In fact, energy efficiency, while important, is only one category of a sustainably designed home. There are four levels of LEED, and each level can be reached by attaining a certain number of points in each of the eight categories.

The eight categories addressed by LEED are:

  • Innovation and Design, 
  • Sustainable Sites, 
  • Location and Linkages, 
  • Water Efficiency, 
  • Energy and Atmosphere, 
  • Indoor Air Quality, 
  • Material Use, and 
  • Awareness and Education.

Innovation and Design awards points not covered in any of the other categories and promotes new ideas, technologies and local variables that come into play in any home construction.

Location and linkages, and Sustainable Sites take into account where a home is built, whether on previously unused greenspace or infill, or “brown land”  (previously industrial, now unused land). The closer you are to services, amenities and public transportation the more points you earn.

Material use emphasizes responsible material use by awarding more points for material that is sourced from rapidly renewable sources (grasses, fast-growing wood, grains), sourcing locally-based materials and products earns more points, as does sourcing recycled and reused materials. Energy and Atmosphere focuses on building a tight building envelope with significant levels of insulation. Indoor Air Quality is also addressed, awarding points for using low VOC producing adhesives, glues, primers, paints and stains. Not only is it better for the homeowner it’s also better for the people applying the products who aren’t exposed to harmful chemicals. Water Efficiency ensures that the fixtures will be low-flow, possibly solar-heated and using an on-demand tank, and if budget permits, a grey water system. Education  and Awareness is about teaching homeowners about their new home and how it best functions.

Depending on the number of points a home achieves in each area will designate it as Certified (45-59 points), Silver (60-74), Gold (75-89) or Platinum (90-136).

A LEED Rater, like an energy auditor, will visit a property twice, once during construction and once when it is complete, in order to assess and make sure construction is following its intended construction path.

For more information on LEED for Homes, visit the Canada Green Building Council’s website.

Passive House: The passive house certification is another one that focuses strictly on energy efficiency. It was developed in Germany more than 20 years ago, and is used as a common standard for home building in Germany today. Homes must use a maximum of 15 kWh/m2 energy for heating, and 120 kWh/m2 per year for electrical plug load, including lighting. Fifteen kWh/m2 was chosen as the threshold because it is at this point that a traditional central heating system is no longer necessary. To achieve passive house standard, especially here in Canada, can be a particular challenge and involves a lot of insulation, superior windows and doors, and a conscientious effort to minimize plug load.

Energy modelling software is used during the design process to determine whether or not a building will achieve the passive house standard. It might be difficult to achieve in an urban environment depending on whether or not a house is situated so that it can take advantage of passive solar heat in the winter, and be shaded in the summer.

For more information visit Passive Buildings Canada.

Living Building Challenge: One of the newest certifications available, it’s also by far the toughest to achieve. At this point, I would say that it is a goal to which the entire building industry should aspire, but it will be done in baby steps. In comparison to the Living Building Challenge, achieving LEED Platinum is basically a cake walk. LBC is divided into 7 performance areas and goals are performance based, not prescriptive. The seven areas are:

  • Site
  • Energy
  • Water
  • Health
  • Materials
  • Equity and
  • Beauty

The categories are further divided into a total of 20 requirements. The purpose of the LBC is to address such issues as inequity in international development (fair trade and encouraging better working conditions) and reducing the amount of energy used both to build a home as well as to run it. In fact, a home must be net-zero energy annually. An LBC home is only certified after one year of energy data has been collected to make sure it’s operating as intended. Materials chosen must be the lowest possible embodied energy and still provide superior insulation, although locally manufactured cement and steel qualify as noted in some of the case studies. A building must be built on previously used land, so no new building in a previous wilderness setting will qualify.

To find out more about the Living Building Challenge, visit the website. One really useful component of the website is the case study section where several buildings which are built to the standard are showcased along with what they achieved in each of the seven categories. In addition, the standard highlights “red” materials, as in, those materials which are to be avoided, such as PVC because of its detrimental effect on the environment. Alternatives are given for each of these materials in the case study section under the Materials category.

Net Zero Energy: The concept of a Net Zero Energy home is simple: produce as much energy as your house consumes over the course of one year. There will be times when you use more energy than your home can produce on its own, and there will be times when you will have excess energy. The concept also means that your home is grid-tied, as in, you draw power from the electrical grid, but you also feed into the grid when you generate excess power. While the concept is easy to understand, implementing it can be a challenge. Not only do you have to create a home that uses as little energy as possible to heat and cool it, a Net Zero Home, takes into account plug load; ie., how many appliances, stereos, computers, game consoles, etc., you have plugged in and drawing power. So, occupant behaviour in a Net Zero home is as important as how well-insulated a home is. It also means that renewable energy sources must be used, such as solar panels, wind turbines, etc., in order for a home to generate a certain amount of electricity — and, naturally, the more people you have living in the home, the more challenging designing a home it will be.

For more information on Net Zero Energy Homes, visit the Net Zero Energy Home Coalition website.


Canada’s Greenest Home to be Built in Peterborough

March 22nd, 2012

Endeavour Centre's next sustainable house, Peterborough, ON

The Endeavour Centre located in Peterborough, ON is a not-for-profit hands-on education centre that teaches students how to build and renovate homes using more sustainable methods and materials than are currently in use. Students learn about building science in the classroom, then take their knowledge onto a building site to apply it.

The people at the Endeavour Centre will build, starting in April, 2012, what they consider to be “Canada’s Greenest Home.” It is being built to surpass LEED Platinum standards, striving instead for the Living Building Challenge certification. This is a recent green designation that is by far the toughest green building standard to achieve. The Living Building Challenge strives for buildings to be, among other things, net zero water and net zero energy use, as well as being constructed using materials with the least embodied energy possible that are healthy, ethical, accessible, sourced as locally as possible and beautiful. The Living Building Challenge certification makes achieving LEED Platinum look like a walk in the park!

To achieve Living Building Challenge certification Chris Magwood, Director of the Endeavour Centre, and his crew are already hard at work sourcing local materials with low embodied energy. Part of this will include prefab walls that consist of straw bales for insulation. While straw bale homes aren’t new, even if they’re not that common, assembling them as a pre-fab structure certainly is. These straw bale walls are built near Peterborough by NatureBuilt Walls, so not only do they provide excellent insulation levels, they are also of very low embodied energy and don’t have to travel a long distance to get to the site. According to the information on the Endeavour Centre’s website, straw bale prefab walls provide an R value between 30 and 40 and are inexpensive to make, mould and mildew resistant, strong, and surprisingly (to me, anyway) are quite resistant to fire. To learn more about straw bale prefab walls, see this presentation.

In addition to pre-fab straw bale walls, the house will include grid-tied solar electricity, composting toilets, an underground rainwater cistern for rainwater harvesting, solar hot water, and natural paints and finishes.

The house will be put up for sale, and the proceeds help off-set tuition costs. The home will be priced affordably, demonstrating that an energy-efficient, state of the art home doesn’t have to be expensive. The house will be built over the course of five months, and at the end, the students completing the program will receive a certificate for their efforts. The point of the program is to give student hands-on green building experience and technical knowledge.

I was curious about how this house would be built and the challenges it will face, so I contacted Chris and asked him a few questions about it.

Cathy:  What will the heating method be?

Chris: We have been intending to use the Mitsubishi Zuba air source heat pump. It is rated to -30C and I’ve heard good things about it from those who have been using it. With the Living Building Challenge, we are basically limited to solar heating and/or heat pumps, as they disqualify any kind of combustion heating, including biomass (which would have been one of our options).

Cathy: What do you envision the overall kWh/sq foot will be? (similar or less than passive house)?

Chris: The PHPP (Passive House’s modeling software) has us at 80% more efficient than code, and their target is 90%. However, we modeled the building in a few different configurations, and found that we needed to nearly double the insulation levels everywhere to move from the 80% to the 90% figure. So we will not be pursuing Passive House certification, as we just can’t justify the additional costs and material use to get to PH levels. We’re very happy with the performance level the model is showing, and feel that we’re in the “sweet spot” where affordable, sustainable materials can be used to make extremely energy efficient buildings.

Cathy: Given the criteria of LBC [Living Building Challenge], how do you anticipate selling it to a buyer who will have to live by strict electricity use? How do you size a solar system to meet that use when you’re not sure what it will be?

Chris: There was a really interesting article in Green Building Advisor recently that looked at the whole notion of designing for net zero, and used two case studies… one in which the occupants used only 36% of the expected energy and another where they were 200+%. The truth is, we don’t know how the owners will behave and we can only design according to accepted averages and see what happens. I’m really not that concerned about getting certified with the LBC. I think it’s a wonderful standard and we’re going to work hard and do our best to meet it, but we can’t control things like the owner’s behaviour or the weather. It would have been easy to hit net zero if this past winter had been our “trial year” but that won’t necessarily be the case next year!
This isn’t the same article, but same message…

Cathy: What will the overall R value be? R 30-40 for the walls, however roofing and basement will be what?

Chris: We’re rating the bale walls at R-30. I believe we’ll see better performance in real life, but that’s at the low end of the test results and that’s what the energy modeler wanted to use. However, because there are no thermal bridges at all (which PHPP calculates in every case), the results were good. We are doing some frame wall sections (to show the students two kinds of wall construction) and they are R-40. We’re doing R-28 Durisol block in the basement and R-80 cellulose in the attic.

Cathy: What kind of landscaping do you plan on including? An edible garden? Shading for summer heat? Green roof of some kind?

Chris: Definitely an edible garden (or the space to make one, since we won’t be planting it during the building season!), fruit trees (learning lots about the service berry tree lately) and all native and drought resistant plantings. There is passive solar shading for both stories on the south side (the skirt roof will hold the thermal collectors). No green roof… I’m not convinced they are a worthwhile investment for single family residences.

Cathy: When do you anticipate it will be ready for market?

Chris: October [2012].

For more information on the Endeavour Centre and sustainable building programs, visit its website.

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