Harmonisation of German building code now critical to allow more serial building

Calls are growing much louder in Germany for a loosening of regulations to permit much more serial and modular building of residential housing units to alleviate the country's housing shortage. 

As we report elsewhere, Germany's main real estate lobby ZIA has stepped up its demands for local authorities to permit 30% of their local housing needs to be constructed using prefabricated and standardised building elements to radically speed up the rate of construction, enabling housing completion in as little as six months.

The difficulty in Germany in introducing such innovative techniques into the building industry across the country has always been the country's Baurecht, or building ordinance. A "type approval" in one state does not apply in other states, seriously hindering the adoption of serial construction outside a specific local region. There is no uniform building law which applies across all 16 federal states, and harmonisation of the 16 different building codes is now urgently needed.

A new study by strategy consultancy EY-Parthenon and the BayWa Group suggests that Germany could immediately increase its housing construction by up to 15% with existing resources, while at the same time gaining cost savings of 10%. This can be done by industrial prefabrication of building components and using digital processing and serial construction, colloquially known as the "Lego Principle".

BayWa manager Steffen Mechter points out in the study that barely any other industry in Germany is subject to such strict legal requirements as the construction industry. Large numbers of people and individual trades are involved in a project, with almost every building a one-off. Moving many of these individual work steps from the site to a factor where components are created automatically, the project would be much less dependent on the weather, and would be easier and faster to complete. The planning and construction of every building from scratch in the conventional way, is a huge waste of existing resources. "The construction of the future must become significantly more digital, standardised and hence more cost-efficient," he says.

"In the case of an apartment building with 25 apartments, for example, this could save 15% of the costs," says Björn Reineke, a consultant at EY Parthenon. Shifting part of the value chain to the factory floor could cut construction time by 30%, equivalent to several months, depending on the structure.

There are several other advantages to element-based construction, says the report. Among them, a high degree of prefabrication reduces the error rate, prevents delays and makes operation on the construction site safer and more efficient. 

Subsequent adjustments to plans often lead to new coordination requirements between the trades and additional costs. These adjustment cost not only time, but money - between 10% and 20% in additional costs. The researchers say that, for an apartment building with 20-30 apartments, cost savings of up to 50% could be achieved through optimising the building process, or a saving of up to 10% on the overall costs of the project. This has been conclusively proved, they say, in both rural areas and in cities, without any concessions to style or design.

While there is only certain scope for individualisation of single or multi-family homes in an estate setting, the benefits are clear in terms of efficiency in planning and the bulk-buying of building materials, says EY Parthenon's Reinicke. The trend towards more serial and modular building is clear and inescapable, he says, with numerous new suppliers and technologies now targetting the segment.