Simple construction—a model for success?
The research project ‘Einfach Bauen’ (Simple Construction) at the Technical University of Munich, led by Prof. Thomas Auer and Prof. Florian Nagler, questions the common practice of relying on high-tech components. Instead, the project investigated whether simple, robust building materials can keep up with high-tech variants in real-world applications. The performance gap—the difference between the key figures determined in the laboratory and the actual performance values—is particularly pronounced in the case of complex components. This is where the pilot project came in, to explore alternative approaches.
‘Einfach Bauen’ is based on single-shell wall constructions that do without additional insulation materials and complex technology. Three identical apartment buildings served as test objects, built using different materials such as solid wood, lightweight concrete and highly insulating masonry. While the first and second parts of the research project developed strategies for energy-efficient, simple planning, construction and measurement, as well as a measurement concept for long-term monitoring, the third part of the research project “Simple Construction 3—Measuring, Validating, Feeding Back” is used to verify the data obtained from measurements and surveys. After two years of measurements at three research houses in Bad Aibling, the final report shows the results in terms of energy efficiency and thermal comfort.
Extract Room comfort
The measurements of thermal comfort were concentrated on the top floor of each house in order to analyse a worst-case scenario with possible overheating in summer. It was found that the positive effect of thermal inertia is greatest in the lightweight concrete house, which increases comfort and prevents overheating, while the solid wood house is the only construction that requires external sun protection on the windows of the west façade to prevent overheating in summer. In terms of indoor humidity, the solid house performed best. The question of whether the assumptions from the simulation also occur in actual use can be answered in the affirmative by the measurements. However, the validation process has shown that the shading of the surroundings by trees and neighbouring buildings has a major influence on thermal and visual comfort in the measurement, which should be taken into account in the simulation in the future.
Extract Energy
The heating energy consumption of all three houses was below the values calculated according to the German Energy Saving Ordinance (EnEV). The solid wood house performed best, but this is also due to the economical heating behaviour of the users. Surprisingly, the brick house consumed more energy than expected due to the inefficient heating and ventilation behaviour of the residents. Since there was no incentive for energy-saving behaviour, even with the assumption of rental and utility costs, the actual individual user behaviour has a significant influence on the indoor climate.
Guidelines for simple construction
The findings from the three research projects are incorporated into the Leitfaden „Einfach Bauen“, which summarise the basic principles developed in the research project for all interested parties. Based on the project parameters and their concrete implementation in the Bad Aibling pilot project, the guidelines offer valuable insights into the strategy behind ‘simple construction’ and a guide for further implementation.