View source for Low-energy house

{{Short description|House designed for reduced energy use}}
[[Image:Passivhaus thermogram gedaemmt ungedaemmt.png|thumb|upright=1.5|alt=See caption|A [[thermogram]] compares the heat radiation of the windows and walls of two buildings: a sustainable, low-energy [[passive house]] ''(right)'' and a conventional house]]{{Sustainable energy}}
A '''low-energy house''' is characterized by an energy-efficient design and technical features which enable it to provide high living standards and comfort with low energy consumption and carbon emissions. Traditional heating and active cooling systems are absent, or their use is secondary.<ref name=":1">{{Cite journal|date=2013-12-01|title=Energy performance of net-zero and near net-zero energy homes in New England|journal=Energy and Buildings|language=en|volume=67|pages=551–558|doi=10.1016/j.enbuild.2013.08.047|issn=0378-7788|last1=Thomas|first1=Walter D.|last2=Duffy|first2=John J.}}</ref><ref>{{Cite journal|date=2014-06-01|title=The convergence of life cycle assessment and nearly zero-energy buildings: The case of Germany|journal=Energy and Buildings|language=en|volume=76|pages=551–557|doi=10.1016/j.enbuild.2014.03.028|issn=0378-7788|last1=Weißenberger|first1=Markus|last2=Jensch|first2=Werner|last3=Lang|first3=Werner|doi-access=free}}</ref> Low-energy buildings may be viewed as examples of [[sustainable architecture]]. Low-energy houses often have [[Active solar heating|active]] and [[passive solar building design]] and components, which reduce the house's energy consumption and minimally impact the resident's lifestyle. Throughout the world, companies and non-profit organizations provide guidelines and issue certifications to guarantee the energy performance of buildings and their processes and materials. Certifications include passive house, BBC—Bâtiment Basse Consommation—Effinergie ([[France]]), zero-carbon house ([[UK]]), and [[Minergie]] ([[Switzerland]]).<ref>{{Cite web|url=https://www.passivehouse-international.org/index.php?page_id=150|title=International Passive House Association {{!}} Criteria|website=passivehouse-international.org|access-date=2019-04-07}}</ref>

Buildings alone were responsible for 38% of all human [[Greenhouse gas emissions]] (GHG) as of 2008, with 20% attributed to residential buildings and 18% to commercial buildings.<ref>U.S. EPA. 2008. Inventory of U.S. Greenhouse Gases Emissions and Sinks: 1990-2006, p. ES8.</ref> According to the [[Intergovernmental Panel on Climate Change]] (IPCC), buildings is the sector which presents the most cost effective opportunities for GHG reductions.<ref>IPCC. 2007. Climate Change 2007 Synthesis Report, p. 59.</ref>

== Background ==
During the 1970s, research on low-energy buildings was done in [[Denmark]], [[Sweden]], [[Germany]], [[Canada]], and the [[United States]]. The implementation of standardized low-energy building concepts has developed differently in each country.<ref>{{Cite web|url=http://www.pibp.pl/wp-content/uploads/dokumenty/European_Embedding_of_Passive%20Houses.pdf|title=European Embedding of Passive Houses.|website=pibp.pl|access-date=2018-12-10}}</ref>

=== Canada ===
In the late 1970s, the province of [[Saskatchewan]] contracted the [[Saskatchewan Research Council]] to design and build a passive solar house suitable for the extreme climate of the [[Canadian Prairies|Canadian prairies]], where winter temperatures can drop to negative 40 degrees Celsius (-40°F).<ref>{{Cite news |last=Huck |first=Nichole |date=2015-08-05 |title='Passive home' movement a success in Germany, but not in Saskatchewan where it started |work=CBC News |url=https://www.cbc.ca/news/canada/saskatchewan/passive-home-movement-a-success-in-germany-but-not-in-saskatchewan-where-it-started-1.3179851 |url-status=live |access-date=2023-10-08 |archive-url=https://web.archive.org/web/20170102070826/https://www.cbc.ca/news/canada/saskatchewan/passive-home-movement-a-success-in-germany-but-not-in-saskatchewan-where-it-started-1.3179851 |archive-date=2017-01-02}}</ref> The project resulted in the construction of the [[Saskatchewan Conservation House]] in [[Regina, Saskatchewan|Regina]] in 1977 by a team led by engineer [[Harold Orr]].<ref>{{Cite web |last=Orr |first=Harold |date=2020-10-05 |title=The principal designer of the house that inspired the global Passivhaus movement reflects on the project that started it all |url=https://www.ecohome.net/guides/1418/the-principal-designer-of-the-house-that-inspired-the-global-passivhaus-movement-reflects-on-the-project-that-started-it-all/ |access-date=2023-10-08 |website=EcoHome}}</ref> The project developed a heat recovery air exchanger (HRV), hot water recovery, and a blower-door apparatus to measure building air-tightness, techniques that became common in low-energy building in other parts of the world.<ref>{{Cite news |last=Procter |first=Don |date=2017-11-29 |title=Passive house on the prairie, the Saskatchewan Conservation House |work=Journal of Commerce |url=https://canada.constructconnect.com/joc/news/projects/2017/11/passive-house-prairie-saskatchewan-conservation-house |access-date=2023-10-08}}</ref> Orr would go on to apply many of those techniques to retro-fitting existing buildings to improve energy efficiency.<ref>{{Cite web |last=Holladay |first=Martin |date=2009-08-14 |title=The History of the Chainsaw Retrofit |url=https://www.greenbuildingadvisor.com/article/the-history-of-the-chainsaw-retrofit |url-status=live |archive-url=https://web.archive.org/web/20181016150831/https://www.greenbuildingadvisor.com/article/the-history-of-the-chainsaw-retrofit |archive-date=2018-10-16 |access-date=2023-10-08 |website=Green Building Advisor}}</ref><ref>{{Cite web |last=Henry |first=Mike |date=2013-08-09 |title=Harold Orr’s Superinsulated Retrofits |url=https://thesustainablehome.net/harold-orrs-superinsulated-retrofits/ |url-status=live |archive-url=https://web.archive.org/web/20170311160654/https://thesustainablehome.net/harold-orrs-superinsulated-retrofits/ |archive-date=2017-03-11 |access-date=2023-10-08 |website=The Sustainable Home}}</ref>

=== Germany ===
Triggered in the 1970s by the first energy crisis and growing environmental awareness, energy conservation became increasingly important in Germany.<ref>{{Cite web|url=http://www.newbooks-services.de/MediaFiles/Texts/9/9783816786139_TOC_001.pdf|title=Basiswissen Bauphysik|website=newbooks-services.de|access-date=2018-12-10}}</ref> In 1977, the country's first energy-related building standard was enacted. The German [[Passivhaus-Institut|Passivhaus Institute]] introduced the first certified passive house in 1990. The annual heating requirement was introduced as an important parameter by the third German Thermal Insulation Ordinance (1995). In 2013, however, there was no clear legal requirement for a low-energy building standard in Germany. According to Maria Panagiotidou and Robert J. Fuller, definitions, policies and construction activity of zero-energy buildings must be clear.<ref>{{Cite journal|date=2013-11-01|title=Progress in ZEBs—A review of definitions, policies and construction activity|journal=Energy Policy|language=en|volume=62|pages=196–206|doi=10.1016/j.enpol.2013.06.099|issn=0301-4215|last1=Panagiotidou|first1=Maria|last2=Fuller|first2=Robert J.}}</ref> The [[European Union]]'s Energy Performance Directive requires that beginning in 2021, only low-energy buildings may be built.<ref>{{Cite web|url=https://www.jurion.de/gesetze/eu/32010l0031/|title=32010L0031 - Richtlinie (EU) 31/2010|website=jurion.de|access-date=2018-12-10}}</ref>

=== United Kingdom ===
Changes to national policies have occurred since May 2015 in the UK. One of the most significant has been the withdrawal of the [[Code for Sustainable Homes]] (CfSH) as a system for assessing and encouraging improvements in the environmental design of dwellings.<ref>{{Cite web|url=https://www.gov.uk/government/publications/2010-to-2015-government-policy-energy-efficiency-in-buildings/2010-to-2015-government-policy-energy-efficiency-in-buildings|title=2010 to 2015 government policy: energy efficiency in buildings|website=GOV.UK|language=en|access-date=2018-12-10}}</ref> This has abandoned the code's schematic which provided a framework of achievement levels and to which low-energy designers could aspire to meet or surpass. Although energy-conservation legislation still exists in the [[Building regulations in the United Kingdom|building regulations]],<ref>{{Cite web|url=https://www.gov.uk/government/publications/conservation-of-fuel-and-power-approved-document-l|title=Conservation of fuel and power: Approved Document L|website=GOV.UK|language=en|access-date=2018-12-10}}</ref> there is a lack of suitable standards exceeding basic regulations. As a result, the Passive House Standard may expand its influence and impact on energy-efficient houses.<ref name=":0">{{Cite journal|last=Pitts|first=Adrian|date=February 2017|title=Passive House and Low Energy Buildings: Barriers and Opportunities for Future Development within UK Practice|journal=Sustainability|language=en|volume=9|issue=2|pages=272|doi=10.3390/su9020272|doi-access=free}}</ref>

=== United States ===
Interest in low-energy buildings has increased in the United States, primarily due to rising energy prices, decreasing costs for onsite renewable-energy systems, and increasing concern about climate change. [[California]] requires all new residential construction to be [[Executive Order 13514|zero net energy]] by 2020.<ref name=":1" />

== {{anchor|Types of low-energy houses}}Types ==
Low-energy houses are broadly defined, but are generally known as houses with a lower energy demand than common buildings regulated by the national building code. The term "low-energy house" is used in some countries for a specific type of building.<ref name=":2" />

A low-energy house is a guideline rarely specified in actual values (heat load or space-heating minimum). A passive house is a standard, with specific recommendations to save heating energy.

At one end of the spectrum are buildings with an ultra-low space-heating requirement which require low levels of imported energy (even in winter), approaching an [[autonomous building]]. At the opposite end are buildings where few attempts are made to reduce their space-heating requirement and which use high levels of imported energy in winter. Although this may be balanced by high levels of renewable-energy generation throughout the year, it imposes greater demands on the national energy infrastructure during winter.

==National standards==
The term "low-energy houses" may refer to national building standards.<ref>Raad Z. Homod, (2014) 'Assessment regarding energy saving and decoupling for different AHU (air handling unit) and control strategies in the hot-humid climatic region of Iraq' [http://www.sciencedirect.com/science/article/pii/S036054421400869X Energy, 74 (2014) 762-774]</ref> These standards sometimes seek to limit the energy used for [[Space heater|space heating]], which is the largest energy consumer in many [[Climate classification|climate zones]]. Other energy uses may also be regulated. The [[history of passive solar building design]] provides an international view of one form of low-energy-building development and standards.

=== Europe ===
Standards for low-energy buildings in Europe have proceeded differently in each country, and there is no common certification or legislation for low-energy buildings valid in all EU member states. As a movement towards reducing energy use and emissions, a common legislation concerning buildings’ energy performance, the [[Directive on the energy performance of buildings|Energy Performance of Buildings Directive]] (EPBD) was published in 2002 and became effective in January 2003.<ref name="EC1">European Commission, "[http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2003:001:0065:0071:EN:PDF DIRECTIVE 2002/91/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 16 December 2002 on the energy performance of buildings]", Official Journal of the European Communities, 2003</ref> 

====Norway====
In NS 3700, the draft official standard, low-energy buildings are defined. About the buildings' energy performance, two alternatives for rating their primary energy use are under discussion:
* A limit on a building's annual [[Carbon dioxide in Earth's atmosphere|CO<sub>2</sub> emissions]], calculated by multiplying the annual supplied energy by a CO<sub>2</sub> factor
* A percentage of its heating demand must be met with renewable energy.

==== Denmark ====
Low-energy houses are defined in the National Building Regulation Building Regulations 08, and are divided into two classes. They are regulated in the regulations' chapter 7.2.4: Low-energy.

==== Germany====
Low-energy houses certified by RAL-GZ 965 have 30 percent less heat losses than regulated in the EnEV, a national building code. Other criteria affect [[Insulation system|insulation]], [[Hermetic seal|air tightness]] and [[ventilation (architecture)|ventilation]]. Low-energy buildings may be certified by RAL-GZ 965 for planning or construction.<ref name=":2">{{Cite web|url=http://lup.lub.lu.se/luur/download?func=downloadFile&recordOId=1585765&fileOId=1585770|title=Low-energy buildings in Europe – standards, criteria and consequences|website=lup.lub.lu.se|access-date=2018-12-10}}</ref>

==== Switzerland ====
Low-energy buildings may receive the [[Minergie]] certification, a "quality label for new and refurbished buildings". The Minergie standard requires that buildings do not exceed 75 percent of average building energy consumption and fossil-fuel consumption must not exceed 50 percent of the average.<ref>{{Cite web|url=https://www.minergie.ch/|title=Minergie Schweiz|access-date=2018-12-10}}</ref>

=== {{anchor|Canada}}North America ===
The European Union directive has clarified low-energy houses in Europe, and a large portion of the discussions on zero-energy building in North America derives from the U.S. [[National Renewable Energy Laboratory]] (NREL).<ref>{{Cite journal|title=Shifting from net-zero to net-positive energy buildings.|journal=Building Research & Information|volume=43|pages=111–120|doi=10.1080/09613218.2014.950452|year = 2015|last1 = Cole|first1 = Raymond J.|last2=Fedoruk|first2=Laura|s2cid=108636555 }}</ref>

The [[Energy Star]] program is the largest certifier of low-energy homes and [[consumer product]]s in the U.S. Although certified Energy Star homes use at least 15 percent less energy than standard new homes built in accordance with the International Residential Code, they  typically achieve a 20- to 30-percent savings.<ref>[http://www.energystar.gov/index.cfm?c=new_homes.nh_features "Features of ENERGY STAR Qualified New Homes."] -  EnergyStar.gov, Retrieved 7 March 2008.</ref> The [[United States Department of Energy]] introduced a program in 2008 to distribute zero-energy housing across the country.<ref>[http://www1.eere.energy.gov/buildings/challenge/about.html "About Builders Challenge."] {{webarchive|url=https://web.archive.org/web/20110903011241/http://www1.eere.energy.gov/buildings/challenge/about.html |date=2011-09-03 }} - March 2008. Energy Efficiency and Renewable Energy, U.S. Department of Energy.  Retrieved 7 March 2008.</ref>

Canadian builders may use a range of standards, labels, and certification programs to demonstrate a high level of energy performance in a given project. These include:
*Net Zero Home and Net Zero Ready Home certifications, administered by the [[Canadian Home Builders' Association]]<ref>{{Cite web|url=http://www.chba.ca/nze|title=Net Zero Home Labelling Program|access-date=May 18, 2019}}</ref>
*Built Green labels, administered by [[Built Green Canada]]<ref>{{cite web|url=http://www.builtgreencanada.ca/about-our-programs|title=About Our Programs|website=Built Green Canada|access-date=May 18, 2019}}</ref> 
*Energy Star for Homes, administered by [[Natural Resources Canada]]<ref>{{cite web|url=http://www.nrcan.gc.ca/energy/efficiency/housing/new-homes/5057|title=Energy Star Certified Homes|work=Natural Resources Canada|access-date=May 18, 2019|date=2011-03-15}}</ref>
*The Canadian Passive House standard, administered by the Canadian Passive House Institute<ref>{{cite web|url=http://www.passivehouse.ca/|title=Canadian Passive House Institute|access-date=May 18, 2019}}</ref>

In [[British Columbia]] the above programs align with the [[BC Energy Step Code]], a provincial regulation to incentivize (or require) a level of [[Efficient energy use|energy efficiency]] in new construction beyond the base building code. The code was designed as a technical road map to help the province reach its target of all new net-zero-energy-ready buildings by 2032.

== {{anchor|Barriers and opportunities for a low-energy house}}Obstacles and issues ==
Energy efficient housing affects [[indoor air quality]]. Airtight houses will trap pollutants inside them, whether produced indoors or outdoors, and lead to an increase in human exposure and potential health issues.<ref>{{Cite journal |last=Niculita-Hirzel |first=Hélène |date=March 16, 2022 |title=Latest Trends in Pollutant Accumulations at Threatening Levels in Energy-Efficient Residential Buildings with and without Mechanical Ventilation: A Review |journal=International Journal of Environmental Research and Public Health |language=en |volume=19 |issue=6 |pages=3538 |doi=10.3390/ijerph19063538 |issn=1660-4601 |pmc=8951331 |pmid=35329223 |doi-access=free}}</ref><ref>{{Cite book |last=UK Health Security Agency |url=https://www.gov.uk/government/publications/climate-change-health-effects-in-the-uk |title=Health Effects of Climate Change (HECC) in the UK: 2023 report |year=2024 |publication-date=15 January 2024 |chapter=Chapter 5: Impact of climate change policies on indoor environmental quality and health in UK housing |orig-date=1 September 2012}}</ref>

Energy-efficient design often relies on new technologies and techniques. These may create technical obstacles in addition to social, cultural, and economic non-technical obstacles.<ref name=":0" />

Buildings designed for good energy efficiency do not always live up to the design goals; various reasons lead to this [[building-energy performance gap|performance gap]].

=={{anchor|Low-energy technology|Introduction}}Technology==
{{Main|List of low-energy building techniques}}
Low-energy building design is considered important to encourage [[resource efficiency]] and reduce global [[climate change]] associated with the burning of [[fossil fuel]]s. Design involves two general strategies: minimizing the need for energy use in buildings (especially for heating and cooling) through energy-efficient measures (EEMs) and adopting [[renewable energy]] and other technologies (RETs) to meet  remaining energy needs. EEMs include [[building envelope]]s, internal conditions, and building-services systems; RETs include [[Photovoltaics|photovoltaic]] or building-integrated photovoltaic, [[wind turbine]]s, solar thermal (solar water heaters), [[heat pump]]s, and [[district heating]] and cooling. Impacts include life-cycle costs, environmental impacts, and climate-change and social-policy issues.<ref>{{Cite journal|date=2013-06-01|title=Zero energy buildings and sustainable development implications – A review|journal=Energy|language=en|volume=54|pages=1–10|doi=10.1016/j.energy.2013.01.070|issn=0360-5442|last1=Li|first1=Danny H.W.|last2=Yang|first2=Liu|last3=Lam|first3=Joseph C.}}</ref> The best low-energy designs offer occupants a better environment and more stable, controlled thermal comfort in addition to reduced energy costs.

GHG emissions associated with buildings construction are mainly coming from:

# Materials manufacturing (e.g., concrete)
# Materials transport
# Demolition wastes transport
# Demolition wastes treatment

The construction, renovation, and deconstruction of a typical building is on average responsible for the emissions of 1,000{{Endash}}1,500&nbsp;kg CO<sub>2</sub>e/m<sup>2</sup> (around 500&nbsp;kg CO<sub>2</sub>e/m<sup>2</sup> for construction only).

Strategies adopted by low-carbon buildings to reduce GHG emissions during construction include:

# Reduce quantity of materials used
# Select materials with low emissions factors associated (e.g., recycled materials)
# Select materials suppliers as close as possible to the construction.
# Divert demolition wastes to recycling instead of landfills or incineration

=== {{anchor|The primary design strategy}}Energy efficiency ===
Reduction of energy consumption is more environmentally and financially advantageous than increasing onsite production to reach a low-energy goal. The less a home consumes, the smaller renewable-energy system it requires to reach net zero. Energy efficiency should always be the primary design strategy of a low-energy house.<ref name=":1" />

=== {{anchor|Improvements to heating, cooling, ventilation and water heating}}Improvements ===
{{col-begin}}										
{{col-2}}
* [[Absorption refrigerator]]
* [[Annualized geo solar]]
* [[Earth cooling tubes]]
* [[Geothermal heat pump]]
* [[Heat recovery ventilation]]
* [[Water heat recycling]]
{{col-2}}
* [[Passive cooling]]
* [[Renewable heat]]
* [[Seasonal thermal energy storage]] (STES)
* [[Solar air conditioning]]
* [[Solar hot water]]
* [[:Category:Solar-powered devices|Solar devices]]
{{col-end}}

==={{anchor|Passive solar design and landscape}}Passive solar design and landscaping===
{{See also|Sustainable landscaping|Sustainable landscape architecture|Sustainable gardening|Rainwater harvesting|Water conservation}}
Passive solar building design and [[energy-efficient landscaping]] support the low-energy house in conservation and can integrate it into a neighborhood and environment. Following [[List of low-energy building techniques|passive solar building techniques]], where buildings are compact in shape to reduce surface area and principal windows oriented towards the [[equator]] (south in the [[Northern Hemisphere]] and north in the [[Southern Hemisphere]]) maximizes passive [[solar gain]]. However, solar gain (especially in [[temperate climate]]s) is secondary to minimizing the overall house-energy requirements. In hot temperatures, excess heat can create uncomfortable indoor conditions. Passive alternatives to air-conditioning systems, such as temperature-dependent venting, have been shown to be effective in regions with cooling needs.<ref>Reda, F., Tuominen, P., Hedman, Å., Ibrahim, M.G.E.: "Low-energy residential buildings in New Borg El Arab: Simulation and survey based energy assessment". ''Energy and Buildings'', Volume 93, 15 April 2015, pp. 65-82.</ref> Other techniques to reduce excess solar heat include [[Brise soleil|brise-soleil]]s, [[tree]]s, attached [[pergola]]s with [[vine]]s, [[vertical garden]]s, and [[green roof]]s.

Although low-energy houses can be constructed from dense or lightweight materials, internal [[thermal mass]] is normally incorporated to reduce summer peak temperatures, maintain stable winter temperatures, and prevent possible overheating in spring or autumn before the higher [[Effect of Sun angle on climate|sun angle]] "shades" midday wall exposure and window penetration. Exterior wall color (when the surface allows choice) reflection or absorption depends on the predominant year-round outdoor temperature. The use of [[deciduous]] trees and wall [[Trellis (architecture)|trellis]]ed (or self-attaching) vines can assist in temperate climates.

===Lighting and electrical appliances===
{{category see also|Energy-saving lighting|Lighting|Windows|Energy conservation|Sustainable energy}}   
To minimize total primary energy consumption, [[Daylighting (architecture)|passive]] and [[Daylighting (architecture)|active daylighting]] are the first daytime solutions to employ. For low-light days, non-daylight spaces and nighttime, sustainable lighting design with low-energy sources (such as standard-voltage [[compact fluorescent lamp]]s and [[solid-state lighting]] with [[LED lamp]]s, [[OLED]]s and [[Solid-state lighting#Polymer light-emitting diodes|polymer light-emitting diodes]] and low-voltage [[incandescent light bulb]]s, [[Ceramic discharge metal-halide lamp|compact metal halide]], [[Xenon arc lamp|xenon]] and [[halogen lamp]]s) can be used.

Solar-powered exterior security and [[landscape lighting]], with [[solar cell]]s on each fixture or connecting to a central [[solar panel]], are available for gardens and outdoor needs. Low-voltage systems can be used for more controlled (or independent) illumination, using less electricity than conventional fixtures and lamps. Timers, [[motion detection]] and daylighting operation sensors further reduce energy consumption and [[light pollution]].

[[Home appliance]]s meeting independent energy-efficiency testing and receiving [[Ecolabel]] [[certification mark]]s for reduced electrical and natural-gas consumption and product-manufacturing [[carbon emission label]]s are preferred for low-energy houses. Energy Star and [[EKOenergy]] are other certification marks.

==See also==
{{Portal|Energy}}
{{div col|colwidth=22em}}
''Buildings''
*[[Zero-energy building]]
*[[Self-sufficient homes]]
*[[PlusEnergy]] buildings
*[[Energy-plus-house|Energy-plus building]]s
*[[Green building]]
*[[Energy audit]]
*[[Yakhchāl]]

''Air and temperature''
*[[Renewable heat]]
*[[Solar thermal collector]]
*[[Solar air heat]]
*[[Solar air conditioning]]
*[[Thermal conductivity]]
*[[Superinsulation]]
*[[Quadruple glazing]]

''Solar''
*[[Passive solar building design]]
*[[History of passive solar building design]]
*[[:Category:Energy-saving lighting|Energy-saving lighting]]
*[[Solar access]]
*[[List of pioneering solar buildings]]

{{em|Sustainability}}
* [[Sustainability]]
* [[Sustainable energy]]
* [[Green building]]
* [[Sustainable refurbishment]]

''Energy rating standards''
*[[House Energy Rating]] (Australia)
*[[Home energy rating]] (United States)
*[[EnerGuide]] (Canada)
*[[National Home Energy Rating]] (United Kingdom)
*[[Leadership in Energy and Environmental Design|LEED - (Leadership in Energy and Environmental Design)]]
*[[Carbon emission label]]
*[[Low-carbon economy]]
{{div col end}}

==References==
{{Reflist}}
{{Reflist|group=footnote}}

=={{anchor|Literature}}Further reading==
*Voss, Karsten and Musall, Eike. ''Net zero energy buildings - International projects of [[carbon neutrality]] in buildings''. 2nd edition, November 2012, Institut für internationale Architektur-Dokumentation GmbH & Co. KG, München, {{ISBN|978-3-920034-80-5}}.
*Raad Z. Homod, ''Intelligent HVAC Control for High Energy Efficiency in Buildings''. [[OmniScriptum|Lambert Academic Publishing]] (2014), {{ISBN|978-3-8473-0625-2}}.
*Per Krusche, Dirk Althaus, Ingo Gabriel, Maria Weig-Krusche: Ökologisches Bauen, Bauverlag Wiesbaden and Berlin, (1982), ISBN 3-7625-1412-7
*Peter Steiger, Conrad U. Brunner, et al.: PLENAR - Planung, Energie, Architektur, Niggli-Verlag, Teufen (1975), ISBN 9978-3-7212-0<nowiki/>078-2

==External links==
* [http://bigee.net/ bigEE - Your guide to energy efficiency in buildings]
* [http://task40.iea-shc.org/ IEA research program "Net Zero Energy Solar Buildings"]
* [http://www.ecbcs.org IEA Energy Conservation in Buildings and Community Systems Programme.]
* [http://www.commonfire.org/green Common Fire Foundation] overview of green building and information on the net-zero-energy Greenest Building in the Eastern US
* [https://web.archive.org/web/20100407123201/http://www.greenbuildingsolutions.org/s_greenbuilding/doc.asp?CID=2150&DID=9058 Article on Low-Energy Housing]

=== {{anchor|External links - examples}}Examples ===
*[http://batchgeo.com/map/net-zero-energy-buildings World Map of international known Net Zero Energy Buildings]
*[https://sites.google.com/site/lowenergyhome/ Building of low energy houses with Insulating Concrete Forms]

{{Authority control}}

[[Category:Low-energy building]]
[[Category:Sustainable architecture]]
[[Category:Sustainable building]]
[[Category:Energy conservation]]
[[Category:Building]]
[[Category:House types]]
[[Category:Sustainable urban planning]]