Screen reader version:

Number of LEED projects registered and certified in top regions by GSM (gross square metres – reported in millions)

Latin America and Caribbean – 1,704 (39.5 GSM)

Middle East and North Africa – 1,297 (69.2 GSM)

North America – 44,998 (611.6 GSM)

Europe – 1,706 (74.5 GSM)

East Asia – 1,995 (107.3 GSM)

271.6 GSM (registered) + 36.5 certified GSM = 308.1 total

Top 10 countries with registered and certified projects

1. United States – 44,270 projects (595.8 GSM)

2. China – 1,156 projects (66.5 GSM)

3. United Arab Emirates – 808 projects (46.1 GSM)

4. Brazil – 638 projects (18.1 GSM)

5. India – 405 projects (6.9 GSM)

6. Canada - 383 projects (7.9 GSM)

7. Mexico – 322 projects (7.9 GSM)

8. Germany – 299 projects (6.1 GSM)

9. Turkey – 194 projects (8.9 GSM)

10. Republic of Korea – 188 projects (15 GSM)

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Wool bricks

Developed by Spanish and Scottish researchers with an aim to “obtain a composite that was more sustainable, non-toxic, using abundant local materials that would mechanically improve the bricks’ strength,” these wool bricks are exactly what the name suggests. Simply by adding wool and a natural polymer found in seaweed to the clay of the brick, the brick is 37% stronger than other bricks, and more resistant to the cold wet climate often found in Britain. They also dry hard, reducing the embodied energy as they don’t need to be fired like traditional bricks.

Solar tiles

Traditional roof tiles are either mined from the ground or set from concrete or clay—all energy intensive methods. Once installed, they exist to simply protect a building from the elements despite the fact that they spend a large portion of the day absorbing energy from the sun. With this in mind, many companies are now developing solar tiles. Unlike most solar units which are fixed on top of existing roofing, solar tiles are fully integrated into the building, protecting it from the weather and generating power for its inhabitants.

Sustainable concrete

While 95 percent of a building’s CO2 emissions are a result of the energy consumed during its life, there’s much that can be done to reduce that five percent associated with construction. Concrete is an ideal place to start, partly because almost every building uses it, but mostly due to the fact that concrete is responsible for a staggering 7-10% of global CO2 emissions. More sustainable forms of concrete exist that use recycled materials in the mix. Crushed glass can be added, as can wood chips or slag—a byproduct of steel manufacturing. While these changes aren’t radically transforming concrete, by simply using a material that would have otherwise gone to waste, the CO2 emissions associated with concrete are reduced.

Paper insulation

Made from recycled newspapers and cardboard, paper-based insulation is a superior alternative to chemical foams. Both insect resistant and fire retardant thanks to the inclusion of borax, boric acid, and calcium carbonate (all completely natural materials that have no associations with health problems), paper insulation can be blown into cavity walls, filling every crack and creating an almost draft-free space.

Triple-glazed windows

The three layers of glass do a better job of stopping heat from leaving the building than standard windows, with fully insulated window frames contributing further. In most double-glazed windows, gas argon is injected between each layer of glass to aid insulation, but in these super-efficient windows, krypton—a better, but more expensive insulator—is used. In addition to this, low-emissivity coatings are applied to the glass, further preventing heat from escaping.

A building that combines all five of these methods would make for a great sustainable housing option. While the construction industry tends to progress at a slow pace, the importance of sustainability is a high profile issue, and one that’s only likely to increase. With sustainable building materials already fully developed, it’s now up to consumers to actively demand their use and building developers to respond promptly.

[box]By Joe Peach at This Big City. This article originally appeared on the sustainable cities website This Big City.[/box]

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Facade of 363 Broadway in Winnipeg, Manitoba

Introduction

This report summarizes the results of pre-and-post retrofit airtightness tests performed on 363 Broadway, Winnipeg, Manitoba. This is a 16-storey office building constructed in 1976 which underwent a major building envelope retrofit during the summer of 2011 to replace the curtain-wall glazing system. The pre-retrofit test was performed on April 14, 2011 while the post-retrofit test was carried out on June 12, 2012. In addition, supplemental tests were conducted on the building’s underground parking facility on June 2, 2012. The tests were carried out for two reasons: to quantify the impact of the retrofit on the airtightness characteristics of the building and to provide data on the airtightness of commercial buildings.

The impact of air leakage on building performance

Air leakage which occurs through a structure’s building envelope is a concern for a number of reasons. First, air exfiltration (defined as the unintentional movement of air from the interior of the building to the outdoors) can transport significant amounts of moisture into the building envelope where it may condense and form interstitial condensation. This can lead to a wide range of damaging and ultimately expensive conditions such as structural distress, corrosion, mould development, etc. Second, air infiltration (the opposite of air exfiltration) can create cold drafts and an uncomfortable indoor environment. Third, air infiltration has the potential to move outdoor pollutants into the building. Fourth, increased air infiltration can lead to unnecessarily high energy costs. Fifth and finally, a leaky structure is usually a noisy structure since the transmission of outdoor noise into the building occurs primarily through the same cracks and openings by which air leakage occurs. Since no structure is perfectly airtight, air leakage, and its undesirable effects, can not be eliminated but can only be controlled within manageable limits.

Test procedure

The test procedure used for 363 Broadway was a modified version of CGSB 149.10-M86 “Determination of the Airtightness of Building Envelopes by the Fan Depressurization Method” (1986). With this procedure, the airtightness is measured by depressurizing the entire structure to a series of indoor-to-outdoor pressure differentials and then measuring the corresponding air leakage rate at each condition. Intentional holes and openings in the envelope, such as ventilation system supply and exhaust grilles, are temporarily sealed so that only leakage through the envelope is measured. Using the air leakage versus pressure differential data, a linear regression curve is then computed to characterize the behaviour of the building. From this data, along with information on the building’s size, the airtightness results can be expressed using various area-or-volume-based metrics.

The major equipment used for the tests consisted of three Retrotec blower door assemblies complete with DM-2 micromanometers/controllers.

With large buildings some judgment is required to define the location of the air barrier and whether specific zones are considered inside, or outside, the test envelope. For 363 Broadway, one such zone had to be addressed: the underground parking garage. This is a three-level, heated garage which has its own HVAC system that supplies treated air to the garage through dedicated air inlets and outlets, although energy for the HVAC system comes from the building. Originally, the parking garage had been included as part of the overall structure being tested and was shown as such in the pre-retrofit test report. However, after consideration, the parking garage (for purposes of airtightness testing) was judged as outside the test envelope since its construction (cast concrete) was completely different from the curtain-wall construction of the rest of the building and because it is intended to be isolated (from an air leakage perspective) from the rest of the structure to prevent carbon monoxide and odour migration from the garage to the building. Therefore, the airtightness results shown in this report for the pre-retrofit condition are slightly different from those shown in the original pre-retrofit report.

There are several methods by which quantitative airtightness results can be expressed. In this report, results are reported using the Normalized Leakage Rate at an indoor-to-outdoor pressure differential of 75 Pa, NLR₇₅. This metric was chosen for consistency with the method used in the National Building Code of Canada. It is also the most common metric used in Canada to express large building airtightness results. The NLR₇₅‘s units are “litres per second per square metre of building envelope (l/s·m²)”, which essentially represents the average air leakage over the building envelope at a standardized indoor-to-outdoor pressure differential. This differential, 75 Pa, is equivalent to that which would be produced by a wind of approximately 40 km/hr blowing simultaneously and uniformly over the entire building envelope area. The building area used for the NLR₇₅ calculation was defined as the total envelope area, including all above-grade components; the parkade was excluded from the tests.

The National Building Code of Canada (NBC) does not (and never has) contained quantitative requirements for airtightness in any type of building.  However, beginning with the 2005 edition of the NBC, it provided non-mandatory “recommendations” for maximum permissible air leakage rates of opaque, insulated portions of the building envelope (2005). This is not the same as the leakage rate for the entire building envelope, such as shown in Table 1, but rather for discrete portions only and does not include glazing or most of the joints and penetrations typically found in a building (and which produce most of the air leakage).  For an occupancy such as 363 Broadway, the recommended maximum leakage rate for assemblies in the NBC is 0.10 l/s·m².

Blower door testing

Results

The pre-retrofit airtightness of 363 Broadway, measured in 2011, was 1.23 l/s·m², as shown in Table 1.  The 2012 post-retrofit measured airtightness was 1.03 l/s·m².  This gave an absolute reduction in the Normalized Leakage Area at 75 Pascals of 0.20 l/s·m², which represents 16.3 percent of the pre-retrofit airtightness. All results exclude the underground parking garage.

Comparative data

To provide additional perspective for the results, Table 2 contains some comparative airtightness data for various large buildings constructed in Canada and abroad over the last several decades (Proskiw and Phillips, 2001).  Most of these were existing structures tested some number of years after construction and would not have been designed or built using modern low-leakage construction techniques. Equivalent, comparative data for commercial buildings in Manitoba is extremely sparse.

Comparing the 363 Broadway results with those of other buildings shown in Table 2, the results from the pre-and-post retrofit tests indicate that the building is surprisingly airtight—displaying a measured air leakage rate which is lower than the mean leakage rates reported in the literature.

Table 3 provides some comparative data on the effectiveness of airtightness sealing in large buildings. Although only limited data is available, it shows that the reduction in air leakage achieved on 363 Broadway is comparable to what has been achieved on other major, building envelope retrofits. Also, of note, most of the buildings shown in Table 3 were initially much leakier than 363 Broadway. This is significant because it’s generally easier to achieve major reductions when the building is initially loose.

References

CAN/CGSB.  149.10, Determination of the Airtightness of Building Envelopes by the Fan Depressurization Method.  Canadian General Standards Board, Ottawa.

National Research Council of Canada.  2005.  National Building Code of Canada.  Canadian Commission on Building and Fire Codes.

Proskiw, G.  and Phillips, B.  2001.  Air Leakage Characteristics, Test Methods and Specifications for Large Buildings.  Report prepared for Canada Mortgage and Housing Corporation.

Table 1

Airtightness Test Results, 363 Broadway Ave., Winnipeg

Table 2

Comparative Airtightness Test Data For Other Buildings

Table 3

Impact Of Air Leakage Sealing On Other Buildings

By Gary Proskiw, P. Eng. of Proskiw Engineering Ltd. A report prepared for the Sustainable Infrastructure Technology Research Group (SITRG) at Red River College.

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A team of researchers at Stanford has designed an entirely new form of cooling structure that cools even when the sun is shining. Such a structure could vastly improve the daylight cooling of buildings, cars and other structures by reflecting sunlight back into the chilly vacuum of space. Their paper describing the device was published March 5 in Nano Letters.

“People usually see space as a source of heat from the sun, but away from the sun outer space is really a cold, cold place,” explained Shanhui Fan, professor of electrical engineering and the paper’s senior author. “We’ve developed a new type of structure that reflects the vast majority of sunlight, while at the same time it sends heat into that coldness, which cools manmade structures even in the daytime.”

The trick, from an engineering standpoint, is twofold. First, the reflector has to reflect as much of the sunlight as possible. Poor reflectors absorb too much sunlight, heating up in the process and defeating the purpose of cooling.

The second challenge is that the structure must efficiently radiate heat back into space. Thus, the structure must emit thermal radiation very efficiently within a specific wavelength range in which the atmosphere is nearly transparent. Outside this range, Earth’s atmosphere simply reflects the light back down. Most people are familiar with this phenomenon. It’s better known as the greenhouse effect—the cause of global climate change.

Two goals in one

The new structure accomplishes both goals. It’s an effective broadband mirror for solar light that reflects most of the sunlight and it also emits thermal radiation very efficiently within the crucial wavelength range needed to escape Earth’s atmosphere.

Radiative cooling at nighttime has been studied extensively as a mitigation strategy for climate change, yet peak demand for cooling occurs in the daytime.

“No one had yet been able to surmount the challenges of daytime radiative cooling—of cooling when the sun is shining,” said Eden Rephaeli, a doctoral candidate in Fan’s lab and a co-first-author of the paper. “It’s a big hurdle.”

The Stanford team has succeeded where others have come up short by turning to nanostructured photonic materials. These materials can be engineered to enhance or suppress light reflection in certain wavelengths.

“We’ve taken a very different approach compared to previous efforts in this field,” said Aaswath Raman, a doctoral candidate in Fan’s lab and a co-first-author of the paper. “We combine the thermal emitter and solar reflector into one device, making it both higher performance and much more robust and practically relevant. In particular, we’re very excited because this design makes viable both industrial-scale and off-grid applications.”

Using engineered nanophotonic materials the team was able to strongly suppress how much heat-inducing sunlight the panel absorbs while it radiates heat very efficiently in the key frequency range necessary to escape Earth’s atmosphere. The material is made of quartz and silicon carbide, both very weak absorbers of sunlight.

Net cooling power

The new device is capable of achieving a net cooling power in excess of 100 watts per square meter. By comparison, today’s standard 10-per cent-efficient solar panels generate the about the same amount of power. That means Fan’s radiative cooling panels could theoretically be substituted on rooftops where existing solar panels feed electricity to air conditioning systems needed to cool the building.

To put it a different way, a typical one-storey, single-family house with just 10 per cent of its roof covered by radiative cooling panels could offset 35 per cent of its entire air conditioning needs during the hottest hours of the summer.

Radiative cooling has another profound advantage over all other cooling strategies such as the air conditioner. It’s a passive technology. It requires no energy. It has no moving parts. It’s easy to maintain. You put it on the roof or the sides of buildings and it starts working immediately.

A changing vision of cooling

Beyond the commercial implications, Fan and his collaborators foresee a broad potential social impact. Much of the human population on Earth lives in sun-drenched regions huddled around the equator. Electrical demand to drive air conditioners is skyrocketing in these places, presenting an economic and an environmental challenge. These areas tend to be poor and the power necessary to drive cooling usually means fossil-fuel power plants that compound the greenhouse gas problem.

“In addition to these regions, we can foresee applications for radiative cooling in off-the-grid areas of the developing world where air conditioning is not even possible at this time. There are large numbers of people who could benefit from such systems,” Fan said.

This article was written by Andrew Myers, associate director of communications for the Stanford University School of Engineering.

Source: Eurekalert.org

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Leadership in Energy and Environmental Design, commonly known as LEED, is a third-party certification program used in over 30 countries around the world to rate high performance buildings, homes and neighbourhoods.

Certifying a LEED building requires following a specific rating system and is administered by LEED professionals with specific credentials.  This article examines the basics of taking a LEED exam and gain LEED Professional Credentials.

LEED Canada

As of 2010 the Green Building Certification Institute administers LEED Professional Credentials for the entire world. Prior to that date the CaGBC (Canada Green Building Council) was responsible for administering the credentials within Canada.

LEED Canada now provides education to aspiring LEED professionals wanting to take the exam as well as those who have attained their LEED Professional Credentials by providing ongoing education.

Who administers LEED exams?

The GBCI provides third-party administration and development, giving the assurance that LEED Professional Credentials are objectively and fairly managed, ensuring that the credentials, exams and eligibility requirements are universal and will stand up to international requirements.

The USGBC, the organization which developed LEED, maintains the information on LEED credentials on its website while the GBCI actually administers the process.

LEED exams

If you want to clearly and easily demonstrate your knowledge of LEED and green building and have an easier time finding jobs that specifically call for LEED credentials, it’s worth taking a LEED exam. There are a few LEED Professional Credentials you can attain, depending on your needs:

LEED Green Associate – This entry-level credential is intended for those who do not specialize in technical fields, such as lawyers, real estate agents and educators. Gaining the LEED Green Associate credential signifies that you have basic knowledge of green construction, design and operations. If you have no technical experience working on a LEED project this is a great place to start. And if you don’t get fully involved in LEED projects then this credential could be all you need.

LEED AP – For professionals like engineers and architects who need more advanced and specific knowledge of LEED and have hands-on experience working on a LEED project. The LEED AP credential offers a number of specialties that denote specialization in particular LEED rating systems:

• LEED AP Building Design+Construction (LEED AP BD+C) – A credential that affirms practical knowledge in design and construction of green buildings for the residential, commercial, education and healthcare sectors.
• LEED AP Operations + Maintenance (LEED AP O+M) – This credential denotes knowledge of sustainable practices that improve performance of buildings and reduce their environmental impact.
• LEED AP Interior Design + Construction (LEED AP ID+C) – A credential for those involved in construction, design and improvement of tenant spaces and commercial interiors.
• LEED AP Homes – A credential specifically for those wanting practical knowledge of the construction and design of green homes.
• LEED AP Neighbourhood Development (LEED AP ND) – This credential is for those who take part in the development, planning and design of sustainable neighbourhoods.

LEED Fellow – This designation is for exceptional professionals in the green building industry. Becoming a LEED Fellow requires being nominated by peers and selected according to evaluation criteria (based on four of five mastery elements of green building: technical proficiency, education and mentoring, leadership, commitment and service, advocacy—technical proficiency must be one of the four).

Maintaining certification

Once receiving LEED credentials, LEED APs and LEED GAs need to maintain their certification by earning continuing education (CE) hours. GAs need 15 education hours and APs 30 hours every two years. For a list of LEED Credential maintenance courses and resources offered by LEED Canada visit this page.

image: Kyoung Koun Park (Creative Commons BY-NC-ND)

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K2TMEVQV4U72 MANHATTAN, KAN. — Kansas State University civil engineers are developing the right mix to reduce concrete’s carbon footprint and make it stronger. Their innovative ingredient: biofuel byproducts. 

“The idea is to use bioethanol production byproducts to produce a material to use in concrete as a partial replacement of cement,” said Feraidon Ataie, doctoral student in civil engineering, Kabul, Afghanistan. “By using these materials we can reduce the carbon footprint of concrete materials.”

Concrete is made from three major components: portland cement, water and aggregate. The world uses nearly 7 billion cubic meters of concrete a year, making concrete the most-used industrial material after water, said Kyle Riding, assistant professor of civil engineering and Ataie’s faculty mentor.

“Even though making concrete is less energy intensive than making steel or other building materials, we use so much of it that concrete production accounts for between 3 to 8 per cent of global carbon dioxide emissions,” Riding said.

To reduce carbon dioxide emissions from concrete production, the researchers are studying environmentally friendly materials that can replace part of the portland cement used in concrete. They are finding success using the byproducts of biofuels made from corn stover, wheat straw and rice straw.

“It is predicted that bioethanol production will increase in the future because of sustainability,” Ataie said. “As bioethanol production increases, the amount of the byproduct produced also increases. This byproduct can be used in concrete.”

The researchers are specifically looking at byproducts from production of cellulosic ethanol, which is biofuel produced from inedible material such as wood chips, wheat straw or other agricultural residue. Cellulosic ethanol is different from traditional bioethanol, which uses corn and grain to make biofuel. Corn ethanol’s byproduct (called distiller’s dried grains) can be used as cattle feed, but cellulosic ethanol’s byproduct (called high-lignin residue) is often perceived as less valuable.

“With the cellulosic ethanol process, you have leftover material that has lignin and some cellulose in it, but it’s not really a feed material anymore,” Riding said. “Your choices of how to use it are a lot lower. The most common choices would be to either burn it for electricity or dispose of the ash.”

When the researchers added the high-lignin ash byproduct to cement, the ash reacted chemically with the cement to make it stronger. The researchers tested the finished concrete material and found that replacing 20 per cent of the cement with cellulosic material after burning increased the strength of the concrete by 32 per cent.

“We have been working on applying viable biofuel pretreatments to materials to see if we can improve the behaviour and use of ash and concrete,” Riding said. “This has the potential to make biofuel manufacture more cost effective by better using all of the resources that are being wasted and getting value from otherwise wasteful material and leftover materials. It has the potential to improve the strength and durability of concrete. It benefits both industries.”

The research could greatly affect Kansas and other agricultural states that produce crops such as wheat and corn. After harvesting these crops, the leftover wheat straw and corn stover can be used for making cellulosic ethanol. Cellulosic ethanol byproducts then can be added to cement to strengthen concrete.

“The utilization of this byproduct is important in both concrete materials and biofuel production,” Ataie said. “If you use this in concrete to increase strength and quality, then you add value to this byproduct rather than just landfilling it. If you add value to this byproduct, then it is a positive factor for the industry. It can help to reduce the cost of bioethanol production.”

The researchers have published some of their work in the American Society of Civil Engineer’s Journal of Materials in Civil Engineering and are preparing several other publications. Ataie also was one of two Kansas State University graduate students named a winner at the 2013 Capitol Graduate Research Summit in Topeka. His poster was titled “Utilization of high lignin residue ash (HLRA) in concrete materials.”

The research at Kansas State University was funded by more than $210,000 from the National Science Foundation. The researchers collaborated with the University of Texas, North Carolina State University and the National Renewable Energy Laboratory in Golden, Colo. The research also involved Antoine Borden, senior in civil engineering, Colorado Springs, Colo.

image: Mazwebs

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12-Year-Old Girl Building Her Own Solar-Powered House — What’s Your Excuse? (via Clean Technica)

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“It is the first radically new and potentially workable alternative to semiconductor-based solar conversion devices to be developed in the past 70 years or so,” said Martin Moskovits, professor of chemistry at UCSB.

In conventional photoprocesses, a technology developed and used over the last century, sunlight hits the surface of semiconductor material, one side of which is electron-rich, while the other side is not. The photon, or light particle, excites the electrons, causing them to leave their postions, and create positively-charged “holes.” The result is a current of charged particles that can be captured and delivered for various uses, including powering lightbulbs, charging batteries, or facilitating chemical reactions.

“For example, the electrons might cause hydrogen ions in water to be converted into hydrogen, a fuel, while the holes produce oxygen,” said Moskovits.

In the technology developed by Moskovits and his team, it is not semiconductor materials that provide the electrons and venue for the conversion of solar energy, but nanostructured metals — a “forest” of gold nanorods, to be specific.

For this experiment, gold nanorods were capped with a layer of crystalline titanium dioxide decorated with platinum nanoparticles, and set in water. A cobalt-based oxidation catalyst was deposited on the lower portion of the array.

“When nanostructures, such as nanorods, of certain metals are exposed to visible light, the conduction electrons of the metal can be caused to oscillate collectively, absorbing a great deal of the light,” said Moskovits. “This excitation is called a surface plasmon.”

As the “hot” electrons in these plasmonic waves are excited by light particles, some travel up the nanorod, through a filter layer of crystalline titanium dioxide, and are captured by platinum particles. This causes the reaction that splits hydrogen ions from the bond that forms water. Meanwhile, the holes left behind by the excited electrons head toward the cobalt-based catalyst on the lower part of the rod to form oxygen.

According to the study, hydrogen production was clearly observable after about two hours. Additionally, the nanorods were not subject to the photocorrosion that often causes traditional semiconductor material to fail in minutes.

“The device operated with no hint of failure for many weeks,” Moskovits said.

The plasmonic method of splitting water is currently less efficient and more costly than conventional photoprocesses, but if the last century of photovoltaic technology has shown anything, it is that continued research will improve on the cost and efficiency of this new method — and likely in far less time than it took for the semiconductor-based technology, said Moskovits.

“Despite the recentness of the discovery, we have already attained ‘respectable’ efficiencies. More importantly, we can imagine achievable strategies for improving the efficiencies radically,” he said.

Research in this study was also performed by postdoctoral researchers Syed Mubeen and Joun Lee; grad student Nirala Singh; materials engineer Stephan Kraemer; and chemistry professor Galen Stucky.

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Based on a philosophy of optimizing for cost and performance rather than compromising, Tedd Benson’s Unity Homes offer both high quality and energy efficiency while being cost competitive. To deliver value to home buyers (including the Passive House standard of air tightness), Benson points to off-site assembly, a method of construction that allows for greater control and a higher quality of craftsmanship than on-site construction. He offers his thoughts about Unity Homes and off-site assembly or montage building.

Why did you choose to adopt the Passive House standard of air tightness with your Unity Homes, but not the other standards that go with Passive House?

The Passive House standard has multiple requirements. Some are more effective than others, and some are more expensive than others. We’re trying to optimize by focusing on controlling  cost and leveraging  for effectiveness. Thicker walls and more insulation is costly and needs to be considered against the value very carefully. We have therefore studied this issue, and our analysis has brought us to the conclusion that after about R30, there are severely diminishing returns with added insulation. At that point, air tightness is a much more significant factor in the building performance. Luckily, air tightness is nearly free. It’s just about good workmanship and good work processes. We can achieve the Passive House air tightness standard on all of our homes consistently, so we focus on that and diminish the PH standard insulation level slightly (R35) to a point where we are getting really good performance, allowing us to use small air-source heat pumps for heating and cooling.

Can you tell me a little about the homes currently in production?

Unity Homes have minimal energy demand, which allows us to eliminate fossil fuels and use an air-source heat pump to supply all the heating and cooling requirements. With this and many other energy features, these homes can achieve net-zero with a modest solar array (5-7 kwh).

We don’t compromise on the structure, as we assume these homes will serve for 300-500 years. In addition, they’re comfortable, light filled, spacious, have great air quality and are filled with great materials, finishes and fixtures.

The Unity standard is the future of homebuilding. You could put it this way: “Nothing compromised. Nothing maximized. Everything optimized.” Or simply “Not too little. Not too much. Just right.”

How far can you transport these houses and how economical is it to transport?

We can ship within a few hundred miles efficiently. This consideration is one of practicality: the distance in which a single driver can make the trip and unload the truck without having to sleep over. We can deliver beyond that, of course, but the costs are higher and need to be more carefully analyzed. Our goal is to extend our production to be closer to our markets. We expect to begin that expansion this year.

A catch-22 facing prefab builders is that volume needs to increase before costs can drop, but for that to happen prices need to be lower for the average consumer. What do you get for the cost of your homes?

That’s right. But it’s not such a bad Catch-22 if we’re strategically accurate as we grow. There are plenty of markets in which Unity is cost competitive now, while providing much higher quality in much faster time. As we grow and bring prices down with scale, we can then bring the Unity proposition to markets where costs are currently lower.

Can you tell me a little about the five key attributes of Unity Homes?

I’ll put this in the form of the Unity Homes goals, and indicate where we are today:

1. Custom home design will be free (currently is).
2. The typical build time will be 20 working days (currently 30 to 35).
3. Living in a home can be free of utility costs and also generate energy for transportation (currently no fossil fuels, net-zero capable).
4. All systems within the home should be continually alterable and upgradeable, with most of the work able to be accomplished by the homeowners (currently disentangled and reconfigurable within the shell, with easy access to most mechanical systems; all homes designed for unpredicted capacity, not just first space plan).
5. Cost for this much higher standard design and performance standard is competitive with current on-site, building-code-based standard (currently competitive with lower quality on-site alternative  in many markets where building costs are at the national average or higher).

What advantages do the Open-Built system offer?

Open-Built improves the efficiency of the construction process by disentangling systems for easier installation. That same disentanglement allows for long-term access, which means homeowners and professionals can accomplish changes, upgrades and renovations with less demolition and rework.

Anything else?

Yes. One BIG thing. Words matter, and the words that are used to identify the current off-site construction methods are insufficient for what we’re trying to accomplish. “Modular” and “prefab” are the usual descriptors. Modular refers to the built volumes that are trucked on the highway like carcasses of beached whales, and prefab mostly connotes a modernist style, with an indeterminate percentage actually accomplished in the prefabrication.

The segment of the construction industry referenced by these two words is wholly failing in three significant ways. First, they represent only 2 to 5 percent of new home construction, and therefore aren’t making enough of an impact on the industry. Second, they aren’t bringing the sort of fundamental quality and cost change to the industry that’s needed because they aren’t doing enough to use the off-site advantage to bring real improvements. Third, they are completely failing to create good jobs. This last one is the worst failure. The employee turnover and absentee rates in those sectors of the construction industry is not only worse than the rest of construction (which in itself is quite bad compared to other industries), but is worse than ANY other industry. This is horrible. Nothing good can come of a building system that leans on low pay, low skill and bad working conditions. We do not want to be associated with it.

Therefore, we’re using the Swedish word for off-site building because it precisely translates into English, German and French (and all of those countries where these languages originated have contributed to our work culture and technology). That word is “montage,” which essentially means “assemble.” One of the Dictionary.com definitions is perfect: “any combination of disparate elements that forms or is felt to form a unified whole.”

We think it’s a better word because the essence of the process is, in fact, assembly. First we assemble the designs from a collection of digital “Lego” elements, rather than starting from nothing to drive down cost, raise quality and still provide a completely custom home; then we assemble the CNC cut parts and pieces in our production studio into the same elements (panels, cartridges, pods, etc); and finally, we assemble the elements on the site to create the complete house. So montage is perfect in that regard.

Most importantly, we need a different word to help us separate the quality of building and the quality of job that are essential to the Unity vision. These two objectives lean on each other for success. You can’t create good jobs with a bad product. Good jobs only pair with the creation of good products. And the reverse is true as well. Good, industry-disrupting products cannot be created unless the people doing the work have good jobs (with good pay, benefits and working conditions) that require discipline, skills, knowledge and a dedication to constant improvement. That’s Unity. That’s montage building.

The post MONTAGE BUILDING: Interview with Tedd Benson about off-site assembly and building performance appeared first on Green Building Canada.

East Amwell man lives off the grid in solar-powered home (via NJ.com)

EAST AMWELL — When Dante DiPirro was 11, he built a contraption from old mirrors that directed the sun’s heat toward a single point. The makeshift solar collector was his sixth-grade science fair project. Now, decades later, DiPirro is still experimenting with sunlight. Calling himself Mr. Sustainable…

The post OFF-GRID: How one man saved $4,000 a year by taking his home off the grid appeared first on Green Building Canada.