Climate protection: For a long time there was too little movement in the construction sector, although greenhouse gases generated by air traffic are often produced here. Michael Wicke shares this point of view. He works as an architect and is involved with climate activists Architects for Future. They show solidarity with Fridays for Future and want to help avert the climate crisis.

Since buildings play a key role in our society’s climate-friendly conversion, this area needs to be looked at more closely, says Wicke. He sees the fact that after more than 20 years there is again an independent construction ministry as a signal that the issue needs to be addressed seriously.

One of the most urgent measures, according to Wicke, is to implement global CO2 pricing, which would then make climate-damaging materials more expensive than renewable materials. However, it is at least as important to include so-called “embodied energy” when assessing the climate friendliness of buildings.

Balancing life-cycle emissions

The lever, says Michael Wicke, is not just better thermal insulation, increased use of renewable energy and greater energy efficiency. Because energy requirements and therefore CO2 emissions arise long before a house is used for the first time. To assess the degree of ecology of a building, it is not enough to focus on heating and hot water. You need a “life cycle analysis”.

It should start with the dismantling, processing and transportation of materials, taking into account the actual construction process, and then the energy consumption during use. Demolition or dismantling should also be considered from the outset.

As a material, concrete is particularly harmful to the climate and the environment. Huge mineral resources such as sand or gravel would be used during production and an “incredible amount” of CO2 would be produced. So if there were CO2 pricing that matched the actual tracking costs of emissions when producing materials, concrete would be a significantly more expensive building material – and other more environmentally friendly materials would be cheaper. so much more competitive.

sustainability in construction

Architects have the power to do without “up to 80% concrete” in the construction of buildings, the climate balance of which is extremely negative. The sustainability criterion must be “at least as important” in construction as the profitability criterion.

Engineer Wicke is convinced that climate-neutral construction is possible. An essential factor is the use of renewable raw materials such as wood, straw and grass. Project examples have shown that houses can even be built “climate positive”. Wood in particular is a suitable building material, provided it comes from sustainable forestry and from the respective region.

However, the Architects for Future movement is not just about a “simple change of material, for example from concrete to wood”, emphasizes Wicke. This does not yet allow for a turnaround in construction. The existing building must be energetically renovated and continue to be used “as long as possible”.

Restoration in all cases before demolition

Demolition should no longer be allowed without permission and holidays should be banned as diversion, he asks. An energy renovation is preferable to new construction, even the most energy efficient.

In this context, the abrupt end of federal subsidy programs for energy-saving renovations and new construction is “incredibly harmful,” according to Wicke. It is true, however, that the programs should be more targeted. It makes little sense to promote what has already become the norm.

Architects for Future is not fundamentally opposed to currently much-discussed serial or modular construction on cost grounds, says Wicke. This does not mean the return of the record. Rather, it depends on the materials used. The wood is also well suited for serial prefabrication of individual components.

In all cases, the aim must be to ensure that as little waste as possible is produced in the interest of the circular economy and that components, such as stairs, are reused even if they are demolished. The topic of climate-neutral construction is also a mandatory part of every architecture degree. “We think it’s essential,” says Wicke.