For the past two weeks my addition to green building knowledge has been focused on the Passive House or Passivhaus Standard of energy efficient building developed by the Germans in 1988. It seems that every week or two I latch onto a new obsession in the world of modern and green building, suck as much information as possible out of it, and then move on to the next concept to obsess over.
Passive House Definition
The basic idea of a Passive House is to reduce the energy usage of a home by 90% over traditional code built homes. I grabbed this definition off of a site which will hopefully become clearer later in the post: “A Passive House is a building for which thermal comfort can be achieved solely by post-heating or post-cooling of the fresh air mass, which is required to fulfill sufficient indoor air quality conditions without a need for recirculated air.”
Key Elements of a Passive House
From what I can find, there seem to be four main aspects to the average Passive House although each one will vary slightly. I have included two things we all like below before going into further detail – a numbered list and a lovely diagram:
- Super Insulation that is airtight and minimizes thermal bridging
- Highly Efficient Windows
- Mechanical Ventilation with Heat Recovery
- Innovative & Efficient Heating Technology
Super Insulation
There are a few key elements of super insulating a passive house:
- High R-Value or Low Thermal Heat Loss Coefficient – For the climate in central Europe which is a tad colder than the northeast US here, they will achieve R-Values of 38 – 52 on all external walls, slab foundation and roofs. This level of insulation reduces the heat lost during the winter and the heat gained during the summer to extremely low levels. It then becomes very easy to keep the home at a comfortable temperature with very little energy. Surfaces in the home will also remain at a constant temperature and enable the home to be kept within safe humidity levels for occupants, furnishings and electronics.
- Construction Reducing Thermal Bridging – Heat will flow through the path of least resistance such as wood, metal or certain foundation materials. Therefore it is important to not only have high insulation values, but to eliminate thermal bridges from the inside of the home to the exterior that are common in typical construction. Thermal bridging will waste the time and money spent on extra insulation if left unchecked.
- Airtight Construction – Building an airtight thermal envelope is important for energy savings, humidity control and ensuring the longevity of the building structure. Gaps in the building envelope will allow moisture to seep in, raising humidity to unsafe levels in the home and damaging the structure of the home over time.
High Efficiency Windows
Windows in a Passive House must be extremely efficient as well to complement the super insulation. In Europe they seek an R-Value of just over 7 which is no easy feat. They use triple pane windows with low-e coatings and Argon gas to reach this goal. They also seek a low U-value of less than 0.20 where a very good Energy Star window in the US will be closer to the 0.30 mark. Below are the three main requirements of windows for a Passive House according to the Germans:
- Triple glazing with two low-e coatings
- “Warm Edge” spacers between the panes of glass
- Super-insulated frames
Mechanical Ventilation with Heat Recovery
Proper ventilation of a Passive House is critical especially due to the air tightness in the home that does not exchange the stale air with fresh outdoor air very much at all. Opening the windows is not a convenient strategy, nor one that can be performed year round. For these reasons a mechanical ventilation system in the form of an HRV or ERV is used to exchange stale air from the most polluted rooms (kitchen, bath, utility) and fresh air is vented into the living quarters (living room & bedrooms).
A Heat Recovery Ventilator (HRV) or Energy Recover Ventilator (ERV) is used in order to recover 75% to 95% of the heat by passing the warm exhaust air past the incoming cold air in a method that does not mix the two streams in order to make sure only fresh air is being vented into the home and no air is being recirculated.
Innovative & Efficient Heating Technology
The heating requirement is so low in a Passive Home due to all of the other factors that usually the home can be heated by simply heating the fresh air that is being brought into the home via the mechanical ventilation system. Various methods can be used to heat the incoming air inline which eliminates the need for additional ducting in the home. Some of the common methods to heat the air in a Passive House include the following:
- Small heat pump
- Small condensing gas burner
- Small combustion unit for biomass fuel
- Compact unit for all in one heating, ventilation and domestic hot water
Finally we’ll end with one of the charts I found from a case study (linked below) on a passive house built in Europe. It shows the effect on the heat requirements of a typical new home in Germany that each measure implemented has on the home.
Key Links:
- Passive House Institute US
- Passive House Case Study (143 page PDF)
- Passive Houses Directory (German site translated to English)
- E-colab.org (US Energy Consultants that have built 3 Passive Homes in Illinois)
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hello, i just came across your site today and am excited to follow your progress. i am confident that you will achieve your goals for this project. are you considering selling your final plans and specs for the finished house so that others can replicate it in their local communities? i am located in berwyn, IL which is an eclectic and up and coming community outside chicago that has the 25′ lots of the city. i think the community would really appreciate the design and priorities of the 100khouse.
Hi Alok,
Welcome to the blog and our project. Yes, we do plan to sell the plans of the 100K House and eventually other similar homes once we are done with this project. The mechanicals are the main thing that will need to be evaluated differently depending on what area of the country you are in, but the basics should remain the same.
I remember the ’superinsulated’ homes that first surfaced in the late ’80s’/ early ’90s’ were too airtight, in that some residents were complaining of allergic reactions to the materials used in construction. I’m not aware of (or don’t recall) whether or not exchangers were successful at mitigating these issues or not. Just a cautionary note.
Carry On! It’s great to be able to ‘watch over your shoulder’ at the process and progress you’re achieving.
Regards, Jerry
Our HRV/ERV system will take care of any allergy issues, especially once we through a nice MERV-11 or 14 filter in there. Thanks for the thought.
Chad-
Maybe you already know about this project in Bemidji MN? They claim to be the first certified “passivhaus” in North America. Stephan Tanner is an architect here in Minneapolis that does consulting in both the US and Germany for this type of project.
http://waldseebiohaus.typepad.com/biohaus/design.html
Roxanne
Roxanne – I am thoroughly enjoying your link. Thanks!
The previously mentioned ‘double envelope’ design for zero energy homes is not a mainstream practice and not likely to become part of the future ZEH best practices. Today’s zero energy homes utilize the same elements you mentioned as the Passive Haus standard with one major exception – the design and specifications need to be climate specific. Also, there is a diminishing point of returns for insulation, windows, etc. beyond which it makes more sense to shift construction costs to another part of the house. Using whole house design with detailed energy models specific to the design in its climate and location is important when validating the cost effectiveness of any package of specs and systems.
Toolbase.org has the best compilation of real world ZEH information. http://www.toolbase.org/ToolbaseResources/level3.aspx?BucketID=2&CategoryID=58
Also, our firm specializes in Energy Design for high performance and zero energy homes.
http://www.zeroenergy.com/pdf/SampleOutline.pdf
You are on the right track. Many of the building practices you are uncovering are on their way to the mainstream now, slowly but surely….
Adam,
Thanks for the links. I have been on your site before and may give you a call shortly to discuss our project in more detail.
- Chad
I’d like to address a couple of misperceptions regarding Passive House, especially those forwarded by “Adam” above. First, contrary to Adam’s claims, Passive House design and specifications are extremely climate specific. The Passive House Planning Package is a powerful and detailed modeling program that has very accurately designed and specified projects throughout the US and the world. Secondly, the old arguments about “diminishing returns” on windows, insulation, etc. simply do not understand the value of a system-based approach to energy efficiency. We are able to remove conventional heating and cooling systems, replacing them with miniaturized ones that are a fraction of the cost and installation… to say nothing of subsequent operational costs and attendant greenhouse gas emissions.
Great input Mike, thanks! I think the Passive House design will become a larger part of future 100K and Postgreen projects due to it’s cost effectiveness and reliance on a whole systems approach that makes sense rather than just specing out expensive HVAC equipment to save on energy…
I just want to reiterate Mike’s comments. The Passive House Planning Package contains climate data for most major metropolitan areas in the United Sates and although it does not currently calculate peak heating and cooling load for all cities, the Passive House Institute expects to have this function available by the end of this year. There is a misconception that this tool only works in Germany, or Europe. The fact is that when it comes to real world examples of super low energy buildings in many different climate zones, the passive house approach is far and away the best thing going because they have actually monitored and published the energy performance of hundreds of structures, comparing the pre-construction PREDICTED results with the ACTUAL post occupancy energy use, and on average the predicted performance correllated closely with the real world. Now it is true that most built examples of Passiv House architecture are in Europe, but at least four have been completed in the U.S. and there is no evidence that the software is any less effective in the U.S. I am currently designing a Passive House and am finding the software invaluable in the schematic design phase. Passive House design is basically synonymous with “whole house design” but is much more scientific and results-oriented.
Very promising project.
I find also very exciting the interest in passive houses all over the world.
I live in the northeast and as you know the climate swings radically from hot and humid to cold and dry. Placement of the vapor barrier is a problem in such a changable environment.We seem to be damned whether it is on the inside or the outside of the insulation. How do address this in the passive house design? I am a big fan if the concept and am ready to build as soon as designs reach maturity.
Thanks,
Larry
Great Site. You guys are doing a fantastic job promoting affordable, sustainable design.
Larry, to respond to your point, even in the Northeast the “delta-T” in heating mode is much greater than in cooling mode, so the vapor barrier goes on the inside. If you are air conditioning your house down to the point that outdoor humidity is condensing in your walls in the summer you are probably not being very energy efficient!
With only an air-to-ground heat exchanger for cooling, a passive house design wouldn’t get that cold in summer.
my house burn
january 1st 2009 and with my wife we have decided
to rebuild our 100 year old house with the passive house concept, we will be pioner in the east cost (Yonkers, NY)
the future is green! we need more promotion about you project nationaly,
it will be great to actualy see the detail cost of 100k house,
as you know in construction there is always more expenses
wich you great success
alex
(sorry for the english i am french)
Hello, I want to know if you have some information about the concept of passivehouse in Mediterranean Clima. Is there any reserch about that?
Regards
It’s ok to both agree and disagree, I assume. The concept of diminishing returns is still highly important, it just is used in different ways for whole house design vs passiv haus. I’ve no mis-conception that PH only works in Europe, nor do I subscribe to Mike’s concept that somehow PH is exempt from diminishing returns because of the envelope focus. Each approach is different and has it’s time and place, and each is a different way to manage where construction efforts and costs are placed. In my humble opinion, the philosophy of each is far more important, and the conditions appropriate of when to use each, in the same way that there are so many modeling programs available, and choosing the right one for the job is important. We’ll shortly have two certified Passive House consultants on staff as one of several great options for achieving high performance homes.
As Dave notes, Passive House design is whole house design. Also, it was not my contention that PH is “exempt” from diminishing returns. My point was specifically to dispute outmoded concepts of diminishing returns, that don’t effectively understand how PH modeling accurately identifies the points at which returns diminish.
With the whole house / ph design. – how is moisture build up within the exterior walls, from condensation, handled ?
moisture build up is handled by controlled ventilation. the units are called Energy Recovery Ventilators for the southern states and Heat Recovery Ventilators for the north. further reading: http://www.fantech.net/hrv_erv.htm
rick – The walls in any well built home should also be built to dry out in both directions (inside and out). With SIPs, this is easy to do.
Here in the Hudson Valley of NY, ultra high efficiency buildings still need heating and cooling. Integrating HRV with a properly sized geothermal heat pump is the perfect way to provide the needed heating cooling and hot water. Due to the significantly reduced load, a very small system is all it takes. Just be sure to install it right. I see as much as a 40% variation in efficiency between installations of the same geothermal heat pump. The efficiency is in the design.
Lloyd – Good input. Would you recommend geo over Solar thermal? Trying to determine what is the best path to net zero energy with the smallest PV array and the least cost…
In Philly we have about 20′ x 50′ in the lots to drill, so we have little room for error.
The one thing I have found tracking solar energy is that its availability tracks opposite to heating need on an annual and daily basis. You can put in storage to deal with the daily/weekly swings but the supply is still the least when you need it the most.
In Philly you should be using only one hole per geothermal heat pump and as long as the holes are at least 20′ apart in any direction you will be fine. We even locate wells under structures where lot space requires it.
The NZEBs I am involved with maximize efficiency in design. When you are going for NZE you have an easy cost decision process, is getting rid of the watt of load more expensive than providing watt from solar.
I have found, and it is backed up by National research and common sense, that in order to get to NZE you must design, construct, commission, train and monitor for NZE and if you leave one step out or do it poorly, the goal will not be gained. Therefor I offer two stages to my consulting work, design and implementation. I will do design without implementation, but the results are not as good. What happens is that the builder thinks he knows how to do it, but can’t pull it off. Air sealing errors and building envelope issues can ruin a project. It turns out that it is not the big things, it is 1000’s of little things. One must remember that the external forces are not diminished, just controlled, and that small breaks in the defenses are huge in an ultra high performance building. There is a 50% gain to be had by doing the same things right. What I am saying is that getting from 30-50% energy reduction takes real money and little intelligence and getting from there to 70% or better takes real intelligence and attention to detail, but little money.
It is the integration of systems that work optimally that ultimately makes the difference for NZE. It is hard to find an HVAC contractor who can or is willing to design for ultra high efficienct buildings because they don’t believe you can pull it off and they have been burned too many times by poorly functioning building envelopes to be trusting. They have also been so beat up on price that they never learned best practice. What one needs in an HVAC system is high functionality with optimum efficiency, not the cheapest one. The real value is in operational efficiency, system durability and life cycle cost.
I have to assume the liability for load design and system function because the HVAC contractor has never seen anything like it and swears the system is 50% or more undersized. Getting properly designed and installed HVAC systems is one of the most difficult tasks in NZEB.
Lloyd – Excellent input. In the Passive House we are just beginning now, we will try to master all of the air sealing details you speak of. We will be using a solar thermal system to provide close to all of our domestic hot water as the system is almost free after rebates. We will use a heat pump HVAC system inline with our ERV to provide most heating and all cooling demand. Supplemental electric radiators (or similar) will be used to provide additional heating as needed.
Our consultants have told us we could get to NZE with as little as a 1.5KW array on this configuration. With state incentives starting at 2KW systems, there is little motivation to reduce demand further…
In the future we will weigh the benefits of solar thermal vs. geothermal more closely. I agree with your concern for installation and already struggle with HVAC sizing. Our first two homes have an HVAC waiver signed by myself as the subs don’t think the design is sufficient…
Thanks again for your comments and I look forward to more insight in the future. We will be posting on details on the Passive project shortly.
Chad,
Sounds good. Remember though that electric heat has a COP of 1 and a properly functioning geo heat pump has a COP of 4, so if you need much heating at all, the life cycle costs demand geo.
With geo you also get to sequester the heat rejected into the ground during cooling to be recovered in heating. Don’t ever look at SEER to determine efficiency as it is a number derived when the heat pump is not under load, much worse than MPG calculations for cars. EERs at operational temperatures are the way to compare air source with geo in cooling.
AMR: for mediterranean clima, you may find some usefull information on the Passive-On Project website.
Passive-On is an european projetct to adapt Passivhaus criteria to the south of Europe.
If you reed french, you can also have a look to my personal project (côte d’Azur).
Your current design is the correct one. Air-to-air heat pump (COP=3) will be at least $7k cheaper than geo (COP=4), so with these near-zero loads the difference is never recouped.
Solar thermal for winter heating also cannot compete with the year-round collection of a net-metered PV system. When the Smart Grid is implemented, the PV advantage will increase because summertime kwh’s will cost more.
Here’s the NREL report that basically says save the DHW solar thermal money and throw it at PV. (It depends somewhat on the rebate/tax credit/subsidy structure, of course). The reason is the poor net system efficiency of solar thermal vs. PV. A net metered PV system has a system efficiency of about 18%, and while a solar thermal system may have a high collector efficiency (over 50%), even on DHW the yearly system efficiency drops to 5%.
http://www.nrel.gov/docs/fy08osti/43188.pdf
Kevin D, MSME, P.E.
http://www.greenbuildingindenver.blogspot.com
KevinD – I was thinking the same thing as I was researching different heat pump systems this weekend. Thanks for the confirmation.
I’m building a new home in 2010 that I believe may qualify as a Passivhaus. Is there a way to officially get it certified as such once the house is completed?
I should clarify: I think there’s a decent chance a home I’m building next Spring would qualify as a Passivhaus. It would be good however to get some feedback as to whether it would be mandatory to throw more money at solar panels or an Apricus solar hot water system to qualify.
Two areas of concern are my heat source and the amount of water that I could potentially be using (and heating). The cottage will be just over 1,300 sq ft and insulated so well that at -20F, it’ll only require around 13.6 kBTU/hr to keep the place at 70F.
The design is complete ICF construction with 18″ thick walls above grade, double ThermaSteel roofing insulation and triple-glazed low-e Fibertec windows. There’s no boiler or furnace. The place will be heated primarily with a small, high efficiency Jotul propane gas stove and supplemented by two electric infrared radiators when needed. The gas stove will have a pilot light, so if the electricity goes, the stove will still work. One indulgence I’m allowing myself will be a a higher-end shower (six heads) that has the potential to use as much as 15 gpm from the well on my land, but we’ll be using a GFX copper heat recovery coil on the shower drain to noticeably increase the temperature of the water going into the on-demand water heaters (of which there will be two.)
Given the shower I’m allowing myself, and the fact that my primary heat source uses propane, would the place simply be disqualified as a Passivhaus, or does the Passivhaus certification focus on the net carbon footprint?
Any feedback greatly appreciated.
John
One final thing I forgot to mention: We will also be installing a Whisper 500 wind turbine capable (at my location) of producing around 570 kWh/month, sufficient for the cottage’s entire electricity needs. I’d simply need a propane tank to fuel the small propane heat stove, to fuel the two on-demand water heaters, the kitchen range, and the gas dryer (which I’d greatly prefer over electric).
John
Hi John,
The Passive House Institute US is the official US Certifier of Passive Houses in the United States. I like to describe briefly the requirements to be recognized as a Certified Passive House Project.
1. The PHPP file, using the PHPP Passive House Planning Package modeling tool, has to be submitted showing that the project energy balance meets all required targets:
*4.75 kBtu/sqft and yr max heating and cooling demand
*38 kBtu/sqft and yr total source energy demand
*0.6 ACH 50 airtightness
A successful blower door test documentation, performed by an independent testing agency is required as well as a photo documentation of all critical details as installed on site accompanied by a declaration from the builder, that everything has been built according to PH specs. The balancing of the ventilation system has to be documented.
Once all those requirements are met, PHIUS (Passive House Institute US) issues the Certificate.
In regards to your project, a typical passive house has a peak heat load of about 5 kBtus in cold climates, so yours still seems a little high. Even though the performance can be determined after the building is designed, it is most of the time unlikely that projects meet the standard after the fact. The standard in cold climates is difficult to meet and the energy optimization through the modeling tool during the planning phase is ultimately the key to achieving the standard.
Active PV is not included in the energy balancing of a Passive House. It is intentionally not a zero energy house because PV is expensive and does not agree with the core principal of Passive House: to combine ecology with economy. Passive Houses are meeting today the 2030 challenge level of 2020 without any active solar.
Once all cost effective energy efficiency measures are in place then the installation of a now very small and cost effective PV system can be used (2-3 kW) to turn a Passive House into a plus energy house/carbon neutral house effectively meeting the 2030 challenge of 2030. This measure can be taken any time between today and 2030.
Solar thermal is calculated into the actual energy balance and can help greatly to achieve the source energy demand requirement.
I like to suggest to reconsider the choice of Fibertec windows. A Passive House requires a high Solar Heat Gain Coefficient (>50%). Fibertech windows only offer to the best of my knowledge a SHGC of 41%.
Kat
Kat:
What great and helpful information. Thank you so much for taking the time.
I did check the spec on the specific South-facing Fibertec windows I’ll be using and they’re listed as “Triple glaze, CL1 Low E, 2 Krypton 2S/S Fixed” with a U-factor of 0.20 (R-5), a VT of 0.59 and a SHGC of 0.51. Looks like they’ve just made the cut.
I’m curious to hear your personal recommendation for windows, especially given the SHGC data you mentioned.
I’m going to share your note with the architect (Russ Hamlet) who’s designed the cottage (www.studiohamlet.com) so I can get his thoughts on what can potentially be done to reduce the peak heat load even further. I’m open to any ideas you may have, too. You’ll find the house plans, elevations and technical details at http://www.orchardman.com .
Thanks again,
John
John,
I took a quick look at your plans and one area I think you should look at is an intentionally conditioned basement. Insulating the basement ceiling leaves you with an unintentionally conditioned basement. I have found great results with insulating the basement walls and floor and making this space part of the building envelope.
Lloyd
Lloyd,
Thanks for the feedback and suggestions. I’ve consciously chosen to keep the basement thermally isolated from the rest of the house because its primary functions are to be that of a root cellar and a workshop where I’ll be grafting and storing trees. In both situations, I’m trying to keep the basement as cool as possible by minimizing the insulation that goes beneath it Further, each of the root cellar rooms will be optimized for a specific temperature and humidity, depending on what’s being stored there. Ideal long-term storage for most fruit (short of an expensive Atmosphere Controlled CO2 storage system) is an environment that’s cold, dark and humid. In the winter, the ventilation system I’ll be using in the cellars will allow these rooms to potentially get down to 40F. It is for these reasons that a comprehensive spray foam insulation system will be going into the basement ceiling, isolating it from the house above. We’ve also moved the location of the basement stairs to an enclosed back porch so the environment downstairs will have minimal effect on the house above.
I hope this makes sense.
By the way, our orchard is very young orchard and won’t require a large barn for a number of years. One eventually we be built that will indeed be the primary storage facility for fruit; I’ve simply put a mini version of this storage beneath the cottage because I want easy access to a fully-stocked root cellar and to the things being grown for personal use.
John
I just visited your site and am very excited since I have always believed that well-insulated and sealed homes could be built that use practically no energy. As you can see from my site mvproject.com we will be constructing a net positive energy home of significant size within 17 miles of Washington, DC. I hope to add Passivhaus compliancy to its mission objectives.
Hi All,
Having read all about Passive house I have now sourced a company who will build, project manage, and deliver my house in 15 weeks turn key, see for yourself they offer a top specification….
http://www.germanpassivehouses.ie/
Paul,
That’s fine if you live in Ireland, which is where that company works.
What sources did you use for this information? Thanks!
Hi Sabrina – My sources are all in the “Key Links” at the bottom of the post. Happy reading.
Hello -
I have been designing a passive house but did not know about the Passive House Institute until yesterday. How does one become a Certified Passive House Consultant? I’m located in Santa Barbara, CA.
Bruce
I am curious where you are finding windows that meet the standards you are referring to here. I have searched the internet quite a bit and am having trouble finding anything that comes close.
I have contacts in China for companies that produce German triple glazed windows using Canadian wood and German hardware. You can buy from Germany ($$$) or directly from the manufacturer in China for a fraction of the price. The only problem is that the Chinese factories do not certify the windows as meeting US standards – yet the details and construction appear to more than meet the standards. Let me know if you are interested.
Serious Windows produces windows to Passive House standards:
http://www.seriousmaterials.com/html/seriouswindows.html
Passive House Institute US—-training is offered throughout US:
http://www.passivehouse.us/passiveHouse/PHIUSHome.html
Bruce,
I have a real problem with windows you are describing. Not only is it not tested so you have no idea of the actual performance and leakage rates are not known. Since unwanted air leaks are a disaster for a high performance house, risking the integrity of the envelope for a savings of a few dollars is silly. On top of that the energy used to transport all of these products back and forth across the globe just to take advantage of cheap labor is just wrong. Wrong for the planet and wrong for a high efficient house. Chasing cheap goods will not get you to the finish line. NEVER use an unrated window if you want long term performance. Also fiberglass is the best frame for a window there is both for performance and long life.
A contractor here in the Hudson Valley of NY just two of his new homes tested with a blower door and both leak less than 200cfm/50. This means that the house is 10 times less leaky than any house the rater ever tested. The buildings are ICF (insulated concrete forms), have triple pane fiberglass windows and a builder who knows what he is doing. By the way, the builder does not even know about passive house standards, he just learned about building science and with my help set about applying the science to construction. What we did was paid attention to the “amplification effect” where the small insignificant leaks become significant because air is compressible and the pressures acting on the building are unabated, increasing the magnitude of the remaining leakage paths. Sealing 90% of the leakage paths only yields about 50% of leakage reduction. Got to get the tiny ones too.
We get solicited all the time from Chinese companies. Let me assure you, Postgreen would not use sub-par products manufactured and shipped from China. It goes against many of the things we stand for…
Interesting comments about products from China. There are many more products in your life that are made in China than you think. Sometimes you really need to do some research to find that a product or many parts of a product are actually made in China. Negative reactions to products from China have driven many suppliers to not openly reveal that their products or product components are made in China.
The windows I mentioned are actually sold in Germany as high quality German windows even though they are made in China with wood from Canada and hardware from Germany (that likely came from steel made in China – from scrap steel shipped from USA – from GM cars made for the most part in Mexico).
For information on CO2 for various transportation modes see: http://about.maersk.com/en/CorporateCitizenship/Environment%20Documents/Energy_consumption1.pdf
On the California coast the CO2 footprint of products from China is likely less than trucking products made on US East Coast.
We are part of one family that spans the entire globe.
We each have our priorities . . . peace bro . . .
I am a little annoyed for the visit of factories in Germany, Austria or Switzerland proves without a doubt that these products are manufactured in these countries. The profiles(wood, or wood+aluminium) used in certified passive house windows come from German (Gutman, Holz Schiller, etc), Swiss (schweizer-metallbau, etc) or Austrian (Internorm, etc) industry. As for the triple-glazed glass, Swiss and german companies are actually leading in tems of performance (I think about Glastroesch or Isolar Glas or even the giant Saint-Gobain with its Climatop plus).
Of course, you do not have to trust me. I can only say that, because I live in Europe (France, Germany and Switzerland) , I have seen en real these high quality products.
Probably top quality products exist in the US. For example, the M.I.T has developped the Heat Mirror solution.