is a vision of buildings that create healthier and more comfortable lives for their occupants without negative impact on the climate – moving us towards a cleaner, healthier and safer world .
is an assessment of building envelope air leakage. This involves establishing a pressure differential across the envelope and measuring the air flow required to achieve that differential. This is normally achieved by utilising variable flow portable fans which are temporarily installed in a doorway, or other suitable external opening .
bioclimatic architecture refers to the design of buildings and spaces (interior – exterior – outdoor) based on local climate, aimed at providing thermal and visual comfort, making use of solar energy and other environmental sources.
Basic elements of bioclimatic design are passive solar systems which are incorporated into buildings and utilise environmental sources (for example, sun, air, wind, vegetation, water, soil, sky) for heating, cooling and lighting the buildings. Bioclimatic design takes into account the local climate and includes the following principles:
- Heat protection of the buildings,
- Use of solar energy for heating buildings,
- Protection of the buildings from the summer sun,
- Using passive cooling systems and techniques, such as natural ventilation, mostly during night time,
- Improvement – adjustment of environmental conditions in the interiors of buildings, i.e. increasing the air movement inside spaces, heat storage, or cool storage in walls,
- Ensuring insulation combined with solar control for day-lighting of buildings,
- Improvement of the microclimate around buildings.
is a roof of a building that is partially or completely covered with non-seeded soil laid over a waterproofing membrane .
is a technical building system or an element of the building envelope .
is the standard consisting of four main areas:
• planning and realisation,
• energy and accommodation,
• construction materials and construction,
• health and comfort.
Each area contains between 8 and 24 sub-items which are awarded with a certain amount of defined points. Similar definitions that include energy as well as other types of items have been or are currently developed in many EU Member States, such as BREEAM2 in the UK or DGNB3 in Germany .
The glass skins can be single or double glazing units with a distance from 20 cm up to 2 metres. Often, for protection and heat extraction reasons during the cooling period, solar shading devices are placed inside the cavity  .
provides a means of rating individual buildings – whether they be residential, commercial or public – on how efficient (or inefficient) they are in relation to the amount of energy needed to provide users with expected degrees of comfort and functionality.
The degree of efficiency depends on many factors including:
- local climate;
- the design of the building;
- construction methods and materials;
- systems installed to provide heating, ventilation, air condition or hot sanitary water; and the appliances and equipment needed to support the functions of the building and its users.
Clearly, certification is a complex procedure, requiring in-depth knowledge of building components. It also reflects increasing recognition of the need to think of buildings as "integrated systems", rather than simply the sum of their parts.
Energy certification of buildings typically involves three main steps :
- The assessment of the energy performance of a building by a competent assessor using a nominated methodology.
- The issuance of a certificate rating the building’s energy performance which includes, in some cases, information on possible improvements likely to yield energy savings.
- The communication of this information to stakeholders through publication of the certificate. For existing buildings, energy certification attests to the energy performance of the building, and provides information that may increase demand for more efficient buildings, thereby helping to improve the energy efficiency of the building stock.
a truly energy efficient house is a self-sufficient house. Working toward self-sufficiency is the way to go toward achieving personal power and freedom.
Self sufficient & energy efficient home plans include:
- Home solar power systems,
- Wind generated power,
- Thermal mass and passive solar home design,
- Energy efficient building materials,
- Rainwater harvesting and storage
- Energy efficient home appliances such as, energy efficient washers and dryers, water heaters, refrigerators, energy efficient windows, and lighting.
- An affordable design,
Energy efficient home design involves two things - finding ways to do things without using energy, and using the least amount of energy to do things that require it .
is the first part of two-step process in terms of being energy efficient rather than a designation of approved performance of the operating building. With examining the energy bills of the building, measuring and verifying of building performance would be assessed, thus the second level would also be performed.
To design a building which is aimed to have an Energy Star, the architects should set a target in terms of energy reduction and for this purpose EPA energy performance rating can be used. According to this rating the target should be higher than the level determined as minimum .
The Green Building practice expands and complements the classical building design concerns of economy, utility, durability, and comfort .
Although new technologies are constantly being developed to complement current practices in creating greener structures, the common objective is that the green buildings are designed to reduce the overall impact of the built environment on human health and the natural environment by:
Efficiently using energy, water, and other resources,
Protecting occupant health and improving employee productivity,
Reducing waste, pollution and environmental degradation .
is a planted roof top that provides benefits of water harvesting, storm water management, energy conservation, pollution reduction and aesthetic value. Green roofs vary in depth of growing media, types of plants (climate-dependent), infrastructure, and intended use .
Green roofs benefit the environment and local communities in many ways:
- They filter the air and water,
- They produce oxygen, absorb heat (during evapotranspiration) and absorb carbon dioxide,
- They provide shade which helps to minimize the impact of the urban heat island effect and reduces the building’s air conditioning requirements, which in turn reduces the greenhouse gas emissions from burning fossil fuels for cooling,
- They absorb rainwater which reduces storm water runoff,
- They provide habitat for urban wildlife,
- They provide leisure and recreational space for building occupants and the local community,
- They insulate the building against external sound,
- They can be used to grow local produce,
- They protect existing roofing, which reduces the number of replacements required and roofing waste.
The basic structure of a green roof is as follows:
- Conventional structural support,
- Waterproof roofing membrane,
- Root repellent system,
- Drainage system,
- Filtering layer,
- Growing medium,
- Plants .
q = U(θi-θe)
where; θi: interior temperature and θe: exterior temperature
Heat gain of buildings may occur in two different ways ;
Solar radiation gains
Solar radiation is introduced into the building through the transparent surface of the building (glazing and walls with a transparent insulation). The amount of sunshine gains depends on the orientation of translucent surfaces and their sizes. Maximum gains of sunshine are expected in the southern areas, less in the east and west ones. For the calculation of solar gains, in addition to the orientation and thermal characteristics of transparent surfaces, it should be taken into account any shading, angle of sunlight and dirt on the windows.
Internal resources gains
Internal sources gains are the result of the release of heat in using electrical appliances and other building equipment. Even people release heat in the surrounding, that is why it is always necessary to take into account the number of fixed users of the appliances, on the calculation. Every person emits heat around 100 W (depending on his physical activity). The quantity of heat generated in the functioning of electrical devices, is often dependent on the number of users. Also regarding the artificial illumination, each lamp emits heat flux (40W, 60W, 100W). Part of the internal gains is reduced on account of evaporation (25W/person) and cold water (5W/person) .
Transmission heat losses
Transmission heat losses are losses due to heat transferthrough the building element as a result of its thermal conductivity.Transmission heat losses are indicated through heat transfer (U) expressed inW/m2K and line heat transfer (Ø - thermal bridges) in W/mK.Transmission losses are reduced by increasing insulation and decreasing thermalbridges.
Ventilation heat losses are losses due to exchange airbetween the building and the surrounding area. Those can be like intentionalventilation (ventilation through windows, mechanical ventilation) or unintendedand unwanted ventilation (ventilation through joints, cracks, etc...).Air-tight windows and building envelop reduce ventilation losses, but at thesame time they disable the supply quantity of fresh air into the building.Therefore, the passive house as well the very good low-energy buildingsrequires the installation of mechanical ventilation systems with efficient heatrecovery.
is an energy recovery ventilation system using equipment known as a heat recovery ventilator, heat exchanger, air exchanger, or air-to-air heat exchanger which employs a counter-flow heat exchanger (counter-current heat exchange) between the inbound and outbound air flow .
HRV provides fresh air and improved climate control, while also saving energy by reducing heating (and cooling) requirements. Energy recovery ventilators (ERVs) are closely related, however, ERVs also transfer the humidity level of the exhaust air to the intake air .
is often used to assess energy performance. It can determine where heat is being lost from the building envelope and can show small differences in temperature , . In the photograph, the red and yellow areas show the heat losses from the building where the blue and green areas show the parts that have good thermal characteristic.
may either be organic materials derived from animals and plants or organic synthetic materials derived from oil or inorganic mineral based materials .
The choice of the material for insulation purposes depends on various factors:
- Insulation efficiency (? values),
- Life of the material (resistance to deterioration by chemicals, moisture changes and fire),
- Human-health friendliness,
- Economy. While choosing the best material from EE perspective, the preference should be given to the ones that are produced with lower energy, e.g. recycled materials, organic materials, etc…
also called sun/solar pipes, solar light, or tubular skylights, are tubes/pipes used for transport and/or distribution of natural light to another location. A light tube uses highly reflective material or plastic optical fiber to lead the light rays through a building. It can also be a prism light guide distributing light uniformly over its length 
is understood in most countries as a building with a calculated energy consumption that is significantly lower than the national requirements. This can be regarded as an informal definition, and was -and still is applied differently in different countries, sometimes even within the same country .
Natural ventilation is often strongly preferred by building occupants, especially if they have some control over it, as with operable windows. Studies have shown that most occupants will readily tolerate a wider range of ambient conditions if they have such control  .
The recast EPBD (2010), in article 9, requests that the Member States shall ensure that:
a.by 31 December 2020, all new buildings are nearly zero-energy buildings; and
b.after 31 December 2018, new buildings occupied and owned by public authorities are nearly zero energy buildings.
Member States shall draw up national plans for increasing the number of nearly zero-energy buildings. Therefore, according to article 9, the Member States must have in their national plans a detailed application in practice of the definition of nearly zero-energy buildings, reflecting their national, regional or local conditions, and including a numerical indicator of primary energy use, expressed in kWh/m² per year. The national plans shall also include intermediate targets for improving the energy performance of new buildings by 2015, with a view to preparing the implementation of nearly zero-energy buildings.
In the period 2011 – 2015, the Concerted Action EPBD foresees a core theme dedicated to the topic Nearly zero-energy buildings. Within this core theme, the national approaches for applying the definition will be gathered and discussed. Plans for policies and support initiatives will be compared, and ideas for such will be exchanged between national representatives.
is the use of the cold night air to cool down the structure of a building so that it can absorb heat gains in the daytime.
This reduces the daytime temperature rise. It is usually applied to buildings that are not occupied at night, although an occupied building would probably be ventilated anyway.
Night ventilation can be driven by natural forces – i.e. stack or wind, but may use auxiliary fan power, either to provide sufficient airflow at times when the natural forces are weak, or to allow smaller ducts (causing greater resistance) to be used  , .
• Maximum calculated net energy use for heating: 15 kWh/m2year,
• Maximum total calculated primary energy consumption: 120 kWh/m2a,
• Required air-tightness value: n50 = 0.6 1/h .
Passive house refers to standard for energy efficiency in a building, reducing its ecological footprint. Passive design is not an attachment or supplement to architectural design, but a design process that is integrated with architectural design.
Although it is mostly applied to new buildings, it has also been used for refurbishments, .
The types of buildings that benefit from the application of passive solar heating; range from barracks to large maintenance facilities.
Typically, passive solar heating involves:
•The collection of solar energy through properly-oriented, south-facing windows
•The storage of this energy in "thermal mass," comprised of building materials with high heat capacity such as concrete slabs, brick walls, or tile floors
•The natural distribution of the stored solar energy back to the living space, when required, through the mechanisms of natural convection and radiation
•Window specifications to allow higher solar heat gain coefficient in south glazing.
Passive solar heating systems do not have a high initial cost or long-term payback period, both of which are common with many active solar heating systems. Increased user comfort is another benefit to passive solar heating. If properly designed, passive solar buildings are bright and sunny and in tune with the nuances of climate and nature. As a result, there are fewer fluctuations in temperature, resulting in a higher degree of temperature stability and thermal comfort. By providing a delightful place to live and work, passive solar buildings can contribute to increased satisfaction and user productivity. In addition, passive solar design does not generate greenhouse gases and slows fossil fuel depletion .
Payback Period = Cost of Project / Annual Cash Inflows
This is achieved using a combination of microgeneration technology and low-energy building techniques, such as: passive solar building design, insulation and careful site selection and placement. A reduction of modern conveniences can also contribute to energy savings, however many energy-plus houses are almost indistinguishable from a traditional home, preferring instead to use highly energy-efficient appliances, fixtures, etc., throughout the house .
First, exterior shading devices result in energy savings by reducing direct solar gain through windows.
By using exterior shading devices with less expensive glazing, it is sometimes possible to obtain performance equivalent to unshaded higher performance glazing.
A second benefit is that peak electricity demand is also reduced by exterior shading devices resulting in lower peak demand charges from utilities and reduced mechanical equipment costs.Finally, exterior shading devices have the ability to reduce glare in an interior space without the need to lower shades or close blinds.
This means that daylight and view are not diminished by dark tinted glazing or blocked by interior shades. With exterior shading devices, glare control does not depend on user operation .
External shading devices are a passive design strategy to control solar heat gain in buildings, and influences energy performance. It can reduce solar heat gain more effectively than interior devices, and its efficiency depends on the provided shading , .
In hot climates, the use of shading devices is desirable, intercepting the unwanted solar rays of overheating period. These elements influence heat gain, especially in relation to location and orientation .
This pressure difference forces outside air into the house through all holes, cracks, and penetrations in the building envelope.
Thus, the term ‘thermal comfort’ describes a person’s psychological state of mind and is usually referred to in terms of whether someone is feeling too hot or too cold. Thermal comfort is very difficult to define because you need to take into account a range of environmental and personal factors when deciding what will make people feel comfortable. These factors make up what is known as the ‘human thermal environment’. The best that you can realistically hope to achieve is a thermal environment that satisfies the majority of people in the workplace, or put more simply, ‘reasonable comfort’ .
(i) the insulation levels in the walls, ceiling and ground or basement floor, including factors such as moisture condensation and thermal bridges that affect insulation performance;
(ii) the thermal properties of windows and doors; and
(iii) the rate of exchange of inside and outside air, which in turn depends on the air-tightness of the envelope and driving forces such as wind, inside-outside temperature differences and air pressure differences due to mechanical ventilation systems or warm/cool air distribution .
Bulk Insulation is relying on the resistance capacity of the materials having pockets trapping air within the structure.
Reflective Insulation is relying on the materials’ reflection capacity of radiant heat flow because of its high reflective and low emissivity characteristics, e.g. shiny aluminium foil coating , .
They don't work as well in cloudy climates or where there isn't a large diurnal temperature swing .
The definition of very low energy buildings varies significantly across Europe even though the EPBD (Energy Performance of Buildings Directive) give guidelines for the calculations. The variation exists not only in terms of the absolute level of energy consumption in a low energy building, but also the deviation from the minimum requirements as stated in the national Building Regulations (see Technical issues). Further the national calculation methods vary from country to country, which makes it rather complicated to compare the absolute values of the energy requirements. The EU project ASIEPI (Assessment and Improvement of the EPBD Impact for new buildings and building renovation), 2007-2010, will make a benchmarking method in order to compare the current energy performance requirement levels in the MS and to make it possible to follow the evolution of the requirements over time. Therefore it was not the intention of this study to compare the absolute level of requirements for the different definitions used.
In addition to structural integrity, moisture is also harmful on human health in terms of the possibility to provide an available environment to micro-organisms.
The dampness in structural elements based on three types:
•Rising or capillary dampness,
•Falling or penetrating dampness,
•Condensation dampness. Water and moisture insulation of an element or a whole-building can be provided by using either flexible materials e.g. bitumen mastic, metal sheets, rubber, etc. and rigid materials e.g. rich concrete, stone slabs, etc...
A Zero Energy Home (ZEH) combines high levels of energy efficiency with renewable energy systems to annually return as much energy to the utility as it takes from the utility –resulting in a net-zero energy consumption for the home .