The certified Passive House
Passive Houses are buildings, in which a comfortable indoor climate can be reached both in winter an in summer - with an extremely low energy input.
The Passive House was developed by Univ. Prof. Dr. Wolfgang Feist in the 1980s. In 1989/90 during a first pilot project 4 row-houses were constructed as Passive Houses, in Germany, Darmstadt-Kranichstein.
Intensive long-term measurements showed that the heating requirement calculated with the PHPP (PassivHaus configuration package) matches perfectly with the actual consumption.
PHPP first appeared in 1998 and has been continuously developed since then. Core of the package are spreadsheets for heat budgets (heating time and monthly procedures), for heat distribution and -supply for electricity and primary energy demand. New modules which are important for planning were successively added: calculation of window parameters, shading, heating load and summer behaviour. PHPP is continuously validated and expanded on the basis of test data and new research findings.
In the meantime on over 300 objects measurement results were compared with calculation results - in the context of accompanying scientific research. The CEPHEUS project in the context of the European Thermie program was of crucial importance. Settlements at 14 European locations and larger residential buildings in Passive House standard were built and scientifically supported. It was found that the thermal properties of buildings - even on Passive Houses – can be depicted with a surprisingly high accuracy concerning the energy program PHPP. This is particularly true for the new method for calculating the heating load.
PHPP is now also available in the following languages: English, Italian, Hungarian, Flemish, French and Swedish. The reasonably priced PHPP includes a user manual that is also a good source of information for the calculation of Passive Houses.
The Passive House is characterized by following criteria: Passive Houses are buildings, which can reach a comfortable indoor climate both in winter and in summer with an extremely low energy input. High efforts concerning design, planning and execution are needed. Passive Houses can be tested and certified to ensure the quality. The existing certification criteria for residential buildings are described below.
Evaluation criteria for the certificate "Quality Approved Passive House":
- Energy specific value thermal heat max. 15 kWh / (m2.a) or heat load max. 10 W/m2 (More information on heating and cooling in Passive Houses)
- Pressure test air change n50 max. 0,6 h-1
- Energy specific value total primary energy max. 120 kWh / (m2.a) including household electricity
Reference (energy reference area TFA) is the net-living space within the thermal envelope calculated by the living space act (WoFlV).
- Note: Because of the fact that calculation errors often occur regarding the calculation of the net-living space this part is one of the largest sources of error. As a benchmark some countries and / provinces use the heated gross floor area. Only out of this difference a different calculation result arises: from 15 kWh/(m2.a) only 12 kWh/(m2.a) arise.
Certification is also available for individual building components and construction products: prefabricated houses, walls and building systems, post-and-beam facades, facade anchors, perimeter insulation for the floor, window frames, glazing, doors, heat pump unit, ventilation systems, ...
There are certain limits for these building components and building products, which must be tested and proved. However, it is not absolutely necessary to incorporate certified products into Passive Houses. Only the above listed three evaluation criterias are essential.
Because of the fact that it has emphasised that customers want a higher level of security concerning the selection of consultants and planners a further certificate has been established: certified Passive House planners. There are two ways to become a certified „Passive House Planner„. Either by having a house certified or by passing the exam. The certificate must be renewed every three years.
Both certificates are appropriate, because they are the only way to ensure the qualitiy of the buildings. Unlike to most of the other denominations "energy-saving house, low energy, zero-energy house, eco-house, ...", on the energetic level the Passive House concept has well-defined, repeatable and demonstrable values for all energy services in the house (warm rooms, hot water, cooled and frozen foods, power in appliances and pumps, artificial lighting, entertainment from television and radio, information from the computer and the Internet, ...).
By numerous measurement studies the Passive House standard could also prove that the real energy consumption is consistent with the theoretical calculation. In sociological surveys of hundreds of Passive Houses residents the standard was described as excellent, pleasant, and future-proofed. They described the standard as a standard which they do not want to miss any more.
The Passive House standard has now been applied on thousands of buildings and has proved itself in a different form for other uses such as kindergartens, schools, students- and old people‘s homes, community offices, office buildings, etc.
The ENERBUILD Tool for the evaluation of public buildings
Main article: ENERBUILD Tool
The tool developed within the framework of the project Enerbuild will be used for the evaluation of the energetic and ecological quality of public buildings. It consists of criteria-lists for different types of public buildings (schools, administrative buildings, etc.) and detailed explanations for each criterion. The catalogue is based on experience, among other things the Nena-tool, the housing subsidy Vorarlberg and the Austrian rating system TQB and "klima:aktiv haus"
The following short overview refers to the internal working version of november 2009 and should be a first overview of the basic structure and the evaluation scheme. The version which has to be elaborated during the project phase will be worked out of the working version. In the further development also the applying-experience out of the practice will flow into the tool.
The evaluation of buildings of a category is based on a catalogue which contains different weighted criteria in a point system, with a maximum of 1.000 points. The criteria are divided into five valuation categories:
|A||Quality of location and facilities||100|
|B||Process and Planning Quality||200|
|C||Energy and Utilities||350|
|D||Health and Comfort||250|
|E||Building Materials and construction||200|
The approximately 40 individual criteria within the five assessment categories are distinguished in ”Must” and ”Optional” criteria. The Enerbuild-tool offers two versions of the criteria catalogue, which differ only in the rating category Energy and Utility:
- Criteria catalogue national building guideline Energy - in this version of the catalogue the certification of the energetic quality of buildings will be adduced by calculations of the energy specific values according to the national assessment guidelines (in Austria OIB-Guideline 6). The most important verification are the heating demand, the demand for cooling as well as the primary energy demand derived from the final energy demand.
- Criteria catalogue Passive House - in this version the verification of the energetic building quality will be adduced by calculating with the Passive House project configuration package (PHPP 2007). Proof sizes are the heating demand and total primary energy demand, additionally PV systems can be evaluated.
The pass mark for a building by rating it accordingly the national building guideline Energy amounts 700 points.
The pass mark for a building by rating it accordingly (the energetic quality) PHPP amounts at least 900 points.
Review and Assessment
With the current state of discussion it will be proposed that the declaration of buildings has to be carried out according to the proofed model of the Austrian „klima:aktiv haus„ within 2 steps:
1st Step: Declaration in the planning stage 2nd Step: Declaration after completion
At each step, the planner / developer / builder declares his building and encloses the necessary documents. Thereafter, a plausibility test by authorized inspectors is carried out. If the declaration and the validation is successfully completed, the project with achieved number of points will be published.
The detailed workflows of declaration and verification will be developed in the course of the project.
ENERBUILD - Catalogue of criterias for public buildings
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