Passive house, zero-energy house or just a "normal house"?
Anyone planning to build their own home will inevitably have to deal with how much energy their house will use later. The German Energy Saving Ordinance (EnEV) sets a certain standard for energy efficiency and this standard must be met by every client. This means above all that certain standards in the insulation of the walls or in the choice of window glazing must be considered. But if you already have a lot to consider, why not go one step further?
The energy efficiency required by the EnEV is already quite extensive. However, there are still a lot of improvements that will guarantee you long-term low energy costs. There are various standards and terms. The best-known standard is certainly the so-called passive house. This has an even higher energy efficiency than envisaged today by the EnEV. Even better, so-called zero-energy houses , even plus-energy houses , are possible today.
As the name implies, zero-energy houses do not require any additional energy and can do their job completely self-supply. In most cases, they use energy from the public grid, but they also emit at least as much energy into the grids.
And it goes even further: Plus-energy houses even generate more energy than they themselves need. That means they are able to self-supply and even surrender excess energy to the grid. Below you will find detailed information about each of these three standards. Maybe you decide to equip your house as future-proof, because the energy prices will not be cheaper.
The generally valid standards of a Passive House are set by the passive house institute in Darmstadt. According to this, a passive house may not exceed a maximum heating requirement of 15 kilowatt hours per square meter in one year. This corresponds to a fuel oil energy content of about 1.50 liters. In addition, the maximum permissible heating load is 10W / m2. This must also be able to be introduced via the supply air in the cold season. Beyond these values, there are a few other factors that need to be considered.
The term passive house comes from the fact that much of the heat requirement must be covered by passive sources. Passive heat sources are the solar radiation, but also the waste heat, which is generated by the inhabitants themselves. Even computers and other electronic devices of daily use help to warm the house.
Passive House standard can certainly be achieved in old buildings through renovation measures. A certain architecture is very beneficial if you want to reach this standard. The compactness of the structure plays a role, as does the planning of the glazing. The building envelope must be air and windproof, heat-bridge-free and have an extremely well-insulated building envelope.
Compared to conventional buildings, passive houses consume up to 80% less heating energy. So you can save a lot of money in the long term. Of course, a Passive House costs a bit more.
Zero Energy House
It's pretty easy to understand how much energy a zero-energy house should consume at most. It can be derived from its name: zero. A house that meets the standards of this standard must produce as much energy as it needs. This is achieved through photovoltaic, geothermal, combined heat and power and very good insulation materials.
Zero energy houses are starting to get a bit more, but most of the buildings that are energy-efficient today are more likely to be passive houses. It's not that hard to go one step further. There are a lot of things to consider when planning. An older existing building can hardly be converted into a zero-energy house, as this requires many architectural forecasts. The house must be ideally aligned with the sun, provide ample space for efficient solar panels and also fulfill other structural requirements that should already be planned during construction.
A zero-energy house must therefore have numerous technical finesse to provide sufficient energy produce and consume as little as possible. Outgoing air heats the incoming air, windows are generous in the south and economical in the north and also the warm water is usually heated by solar power or other possibilities.
Plus energy house
To the given level of a plus energy building Passive House standard is an advantageous base, but not enough. There are still many, far-reaching measures required. A plus-energy building generates more energy than it actually consumes. It is therefore the highest energy standard that a home can achieve today. Plus energy houses are made possible by the use of renewable energies (such as solar energy or the use of renewable resources, usually in combination with combined heat and power). A plus-energy house must have just about every technical finesse and state-of-the-art insulation that exists today.
Plus energy houses are so far not an official standard . There are still very few buildings that meet the previous requirements. Above all, these are test projects, university projects and the like. Residential buildings in plus energy standard, there is almost no. Anyone planning a low-cost residential building today is surely the better target for achieving passive house or zero energy house standards. But if you want to dare something and find the right partner for planning and execution, you can bravely go ahead and set an example.
Artikelbild: © nikkytok / Shutterstock