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Background: Saving the climate or destroying culture? Energy renovation at the crossroads

The distance from bearer of hope to problem case can be short as is shown by the current situation of energy-efficient refurbishments in Germany. In the country that, up to now, has often been regarded as a pioneer with regard to energy-efficient building, it is possible to ascertain how far political intentions and the reality of energy renovation can be removed from one another - and how far there is to go until all the building stock in Europe has been renovated. rnIn its energy concept, published in autumn 2010, the German Federal Government announced that it is aiming for a 'climate-neutral' building stock by 2050. The proportion of all buildings in Germany that are renovated to improve their energy efficiency each year would therefore have to double from 1 % to 2 %. Five years later, the political targets still remain. But the public discussion on energy renovation has changed considerably, being regularly fuelled by newspaper articles and television documentaries with titles such as, "The Madness of Thermal Insulation". Their message in brief: The energy renovation of buildings is damaging to building culture, does not make economic sense, and is ecologically absurd as a lot of the insulation material used is non-recyclable. rnThe change in direction is now also noticeable in the real-estate market. In a recent survey of real-estate agents, 44 % of all those questioned said that the energy standard of apartment buildings no longer had any influence on rent levels. At the same time, more estate agents than ever before reported that buyers and tenants have become less concerned with the energy standard of buildings. rnTo find ways to resolve the present situation, a holistic consideration of all levels of energy renovation is essential. These are far more varied than is suggested in public discourse, which is often reduced to the conflict between ecology and economy.

Background: Saving the climate or destroying culture? Energy renovation at the crossroads
Refurbishment of an office building in Bolzano, Michael Tribus 2005: With the first ever Passive House refurbishment of an office building, the theme of chamfered window reveals was (re-)introduced into contemporary architecture. This device allows for ample daylighting in the interior rooms, despite thick insulation layers on the facades. © René Riller

The ecological level

The practice of attaching polystyrene and other oil derivatives to building facades in order to reduce fuel consumption seems counter-intuitive to many people. From a purely energy point of view, however, the trade-off is justifiable. If the uninsulated, or poorly insulated, wall of an existing building (U > 0.5 W/m2K) is renovated to bring it up to the level of a new building (U = 0.23 W/m2K), the embodied energy in the insulating material is amortised by savings in heating energy within a maximum of one and a half years.

The fact that such fundamental facts are still frequently misconstrued – including by some professionals – is also connected to the negative image of many thermal insulating materials in Germany. Two of the main problems here are, firstly, the supposedly short lifespan of composite thermal insulation systems and, secondly, the fact that they cannot be recycled. These notions are so widespread in Germany that they have practically become a synonym for energy renovation.

The design level

Even in the public media, the term ‘building culture’ has started to crop up in connection with the insulation of existing buildings. The warnings of many architects against the ill-considered ‘packaging’ of historic buildings in insulating materials seem to be gradually trickling down to the public.However, the question arises as to whether every stucco moulding and every stone lintel are really worth preserving. The prevalent nostalgia for the charming features of old buildings that are being lost due to renovation is also the result of the crude design and sterile sleekness of many facades that have undergone energy renovation. Counter-examples, such as those of the Munich architects Hild und K, which demonstrate that facades can also be designed three-dimensionally with insulating materials, are all too rare (Fig. 5).

The economic level

At around 3 % per year, the cost of energy renovations in Germany has risen significantly faster than average prices in recent years. A reversal of this trend is unlikely due to the generally strong construction industry in Germany. This particularly applies to established technologies in the low-price sector, which make up the bulk of the renovation work being carried out. There is definitely room for cost reductions in isolated areas such as innovative insulation materials or ventilation systems with heat recovery. All in all, however, there is little hope that renovating in Germany will become less expensive in the future.

The political level

The legal stipulations relating to energy renovation are becoming less and less popular in Germany and are often perceived as state interference in the property of private owners. In the latest amendment to the German Energy Saving Ordinance, the government therefore refrained from tightening the regulations for the renovation of existing buildings.

In any case, the programmes promoting energy-efficient building and renovation now seem to rest on a secure financial basis. But the 1.8 billion euros that flow into the corresponding programmes from government coffers will hardly be enough to achieve the political goal of a climate-neutral building stock in 2050. Each of several studies has independently come to the conclusion that three to five billion euros a year would be necessary.

The qualification level

Like many other European countries, Germany has had bad experience in the past with ill-conceived and poorly implemented energy renovations. In view of the importance of the issue, it is also astonishing how small a role construction measures for existing buildings play in the curricula of faculties of architecture in Germany. When it comes to skilled trades, the situation is not much better.

Politicians are therefore trying to counteract this. As of the middle of 2014, public grants are only given to renovation projects planned by accredited energy consultants. In order to be added to the consultants’ list of the Deutsche Energie-Agentur (dena), it is stipulated that planners have either undergone extensive further training or completed relevant reference projects.

The urban level

A large number of uncoordinated renovation measures carried out on individual buildings is not necessarily the best way to achieve energy savings in the most cost-efficient manner. Starting in 2011, the semi-governmental development bank, KfW therefore has been offering a range of funding services that helps communities to implement neighbourhood renovation projects. This usually includes two large components: energy renovation of the building stock and concepts for the communal supply of heat and electricity. Apart from this, an important component of the funding programme is the financing of so-called ‘renovation managers’. These are individual people or planning teams who draw up the renovation concept on behalf of communities in consultation with local residents. Experience gathered in the projects funded so far shows how vital the role of coordinator and communicator is for successful renovation.

Summary and outlook

What does the future look like for energy renovation? Several theses can be derived from what has been stated thus far:

• The technologies needed for energy renovations are (mostly) already available. Rigorous quality assurance and continuous education and training of all the parties involved are more fit-for-purpose − and also more confidence-building − than waiting for more, ground-breaking technological innovations. Important political groundwork for this has been undertaken in the past few months.

• Germany will probably fail to reach the target of doubling the rate of energy renovations. The public funds available for financing them are insufficient – and an increase is not anticipated at present. The demand for energy renovations could soon rise again due to escalating energy prices (e.g. due to the Ukraine crisis) but, if the aim is to really increase the rate of renovations, a politically controlled rise in oil and gas prices is unavoidable – whether this means higher taxes on fossil fuels or inclusion of the heating sector in EU-wide CO2 emissions trading.

• The issue of renovation is about more than merely energy – and it is necessary to sharpen awareness of all the dimensions involved. The quality of design and execution is difficult to express in terms of statistics and hence is often overlooked by political decision-makers. Nevertheless, many building owners are well aware of the added value of being able to obtain independent and holistic advice. Both of these are core competences of architects. However, if they are to be utilised to the full, further training of all architects – and not only the listed energy consultants – in energy questions is imperative.

Gallery

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