Will the investment in a passive house pay off? Can windows be opened in an energy-efficient building? Can only single-family houses be realized in high energy standards? Are heat pumps a universal solution? We talk about the facts and myths of passive and zero-emission buildings with architect Kamil Wiśniewski, owner of GreenCherry Architecture studio, director of the Polish Passive Building Institute and founder of Akademia Zdrowego Budownictwa.
Ola Kloc: What are the biggest myths circulating around the topic of passive and zero-energy construction?
Kamil Wiśniewski: Indeed, the same myths have been circulating around passive, zero-energy or highly energy-efficient buildings for many years, and we have been dealing with them all the time, despite the fact that "this construction" has been with us for more than 30 years, and is now almost 20 years old in Poland.
Until the outbreak of the energy crisis and significant changes in the construction law regarding the increasingly higher energy efficiency requirements for buildings, the aforementioned myths have had time to grow and settle into popular consciousness. They particularly concern several issues in the area of misinterpreted advantages of the passive building standard and the cost of its implementation. That's why I'm happy about our conversation today, and I'm convinced that it too will be another brick in building greater awareness among investors and those professionally involved in the construction process.
It is worth mentioning here that in our country, since 2005, knowledge about buildings realized in the highest energy standards has been passed on through conferences, publications or other educational actions by the Polish Institute of Passive Building and Renewable Energy, based in Gdansk. In addition, I personally have the pleasure of leading for more than a decade Akademia Zdrowego Budownictwa, which is an integral, accredited training unit of the Polish Institute of Passive Building and the Institute of Passive Building in Darmstadt. The Academy educates professionals and investors in the implementation of passive, zero-energy or highly energy-efficient buildings — regardless of their size, construction technology or purpose.
Despite our long-standing efforts, the several thousand participants we have hosted at our events: conferences, webinars, certified training programs, there is still much to do to make these myths disappear and stop being reproduced.
MYTH #1 No ability to open windows
Many people mistakenly believe that the outer shell of such a building, whose function is, among other things, to reduce losses to a reasonable minimum and which can be likened to the performance of a shell in a thermos, is unequivocally associated with the inability to open windows.
MYTH #2 Significantly higher implementation costs, compared to buildings constructed in the traditional way* (*according to currently applicable technical conditions)
There is also a belief that this type of investment is many times more expensive and has no possibility of paying for itself. The question "when will it pay for itself?" was probably one of the most frequently asked by some as yet unaware private and institutional investors. Nowadays, in the context of changes and the energy transition that has begun, targets imposed on the entire construction sector — also with regard to reducing CO2 emissions, rising energy costs, and thus the operation of buildings, this question is being asked less and less.
MYTH #3 High energy standard = single-family frame house
Another example is the question of combining a high energy standard with size, purpose, erection technology or heating, cooling and ventilation systems. More often than not, investors mistakenly combine the passive building standard with timber frame technology and come from the misconception that the aforementioned standard is intended only for single-family buildings.
For many years, during lectures, training programs on passive and zero-energy construction, I have been imparting knowledge to professionals using examples of many such buildings, constructed with different technologies, cubic capacity and purpose: multi-family, office buildings, kindergartens, schools, production halls, hotels, stores, health centers, etc.
example of an office building in passive standard
© Akademia Zdrowego Budownictwa
example of a building complex in passive standard, production hall with office building
© Akademia Zdrowego Budownictwa
Ola: So let's face these myths — can you open these windows or not?
Kamil: It is even required! Buildings in the highest energy standards — this includes passive buildings, as well as zero-energy or highly energy-efficient buildings (these names, in addition to the clearly defined parameters of the passive building standard, some more have been created) — must have at least one window open for each room intended for permanent human residence.
It should also be borne in mind that in addition to the specified rules of the passive building standard, the overriding role will always be played by the regulations/technical conditions that apply in a given country. There have also been many doubts about this issue.
It is true that opening windows disturbs and reduces the efficiency of, among other things, mechanical ventilation or heating/cooling systems, and this translates directly into the energy balance of a building. Regardless of its purpose or scale. However, there are cases in which opening windows in a passive or zero-energy building can also have a specific function — natural ventilation mainly during transitional periods and in summer — cheap and fast removal of accumulated air with excessive temperature from the building. Such work would be performed by a mechanical ventilation system many times longer and with much higher energy expenditure.
There is also nothing to prevent the use of opening windows in buildings in the highest standards for other purposes. However, this should be accompanied by specific behavior on the part of the investor — turning off mechanical ventilation and heating/cooling systems for that time, or equipping the building with automation that will do it for him. Otherwise it will reflect badly on the building's energy balance and increased operating costs, despite the high standard!
Ola: So let's move on to another myth, let's talk about money....
Kamil: It is important to look at this aspect with the market background in mind. We are in the early stages of a very dynamic change, an energy transformation in the construction sector on a huge scale. It will affect by 2030 and then 2050 practically all owners, users of real estate. It has a fixed time caesura. We know exactly what regulations, additional obligations and fees begin to take effect in the following years. Owners of energy-intensive buildings and those operating on the basis of non-renewable energy sources will be affected severely.
Starting in 2024, new energy classes also take effect. There is no way that the new regulations (including the introduction of ETS 2), requirements, the mentioned energy classes will not affect the prices of all properties and change the way they are valued. The energy efficiency of a building becomes a key selection criterion and a significant component of its valuation in the following years. Thus, the question of how long it takes to pay back an investment in a building with a standard to which the whole market is moving anyway is no longer relevant.
It is worth noting that it was the same with electrical appliances. Today, few people want to buy appliances that have an energy class of C, D, E, because low energy classes of appliances are a clear indication to us that they will be more expensive to operate. This is despite the fact that few ask themselves and count how much more expensive it will actually be. The same effect will be seen in a moment with buildings. Those that are energy-intensive, expensive to maintain or require very high expenditures for a major upgrade will become cheaper and hard to sell. With the above issues in mind, investing in a passive, zero-energy building standard was and is currently the most advantageous possible solution. This will be confirmed by any designer, civil engineer, contractor, investor who has gained full interdisciplinary knowledge of buildings in the highest energy standards — both new and retrofitted.
The changing attitude of the financial sector is also not insignificant. In a short while it will become much more difficult or even impossible to obtain financing to buy an energy-intensive building, or there will be a realignment of its valuation by the cost of the necessary upgrade to high energy standards. Such action is already taking place in some European countries.
Today, more and more investors need our help. They are looking for solutions because the costs of maintaining buildings are beginning to exceed the costs possible from running their business. This is true for office buildings, boarding houses, private kindergartens, schools, hotels, where energy costs are an important part of the overall business. With a building at the highest energy standards, we reduce the necessary energy by 90%, the total operating costs drop by 50-60%, and thus the profits from running the business are on a completely different level.
continued conversation on next page