Residental complex waterproofed


The exclusive “Seewinkel” residential complex was built on the southern shore of “Phoenix-See”, a lake in Dortmund, over the period between the end of 2018 and spring 2020. In this construction project, MC spray sealants were able to once again demonstrate their strengths in terms of quality and speed of application.


Phoenix-See in Dortmund is an artificial body of water on the 96-hectare site of the former Hermannshütte smelting works in the municipal district of Hörde. An upmarket residential environment has been created as a lighthouse project around its southern shore as a further example of the structural transformation occurring in the city.

Inspired by a project report in MC aktiv

The ambitious “Seewinkel” build on the south side of Lake Phoenix was completed in April 2020. Its 26 apartments each have a terrace or a balcony plus a parking space in the underground car park. The homes were built by Freundlieb Bauunternehmung GmbH & Co. KG of Dortmund under the project management of construction engineer Christoph Weischenberg. “I was interested to read the report in MC aktiv about the waterproofing of a hospital in Duisburg (Germany) using spray-on sealants. That resonated as an ideal solution, so we applied the same technology in our Seewinkel project,” Weischenberg explains. Having thus decided against using welded sheeting and in favour of this spray-on barrier solution from MC, he commissioned the specialist firm M + M Pistohl GbR of Senden (Germany) with the application work. The waterproofing had to be executed within a strict time frame, yet with the assurance that the surfaces involved would be sealed with maximum efficiency. The sealant selected was Nafuflex Profi Tech 1, a compound especially developed by MC for airless spray application. 


This fast-drying, single-component, sprayable polymer-modified bitumen thick coating (PMBC) is approved in accordance with DIN 18533 for waterproofing buildings for water exposure classes W1-E, W2.1-E, W3-E and W4-E. In this case, the walls were sealed with Nafuflex Profi Tech 1 in a dry layer thickness of 4 mm. In critical areas such as construction joints, the system sealing tapes of the MC-FastTape series were also used as part of the integrated solution.

View of the exclusive “Seewinkel” residential complex.
View of the exclusive “Seewinkel” residential complex.
© MC-Bauchemie 2024

Reactive sealant for efficient waterproofing

The specification both for the base area of the external façade and the underground car park foundations was for a sealant offering particularly good resistance to freeze-thaw cycling and de-icing salts, as well as excellent waterproofing performance. So, the decision was made to use MC-Proof eco, MC's fast-setting, highly flexible and bitumen-free reactive sealant. It can be plastered-over and is UV-resistant, making it ideal for outdoor use. In the plinth area, there were also many floor-to-ceiling windows that had to be fitted and sealed. The primary challenge in such cases usually derives from the frequent material changes involved, with welded membranes and liquid resins alternating. However, the MC proposal involving MC-Proof eco meant that this mix was avoided, making the work much faster and the end result visually more attractive.


Positive balance

Following on-schedule completion of the work, project manager Weischenberg noted with satisfaction: “It was important for us that MC, as the product supplier, provided its own application engineers to support the waterproofing work, thus making sure that the task was carried out with expert precision to the specified quality standard. As a result, everyone involved enjoyed the experience of a job well done.”

abs 123 abs 123 abs 123 abs 123 abs 123 abs 123 abs 123