Zur Hälfte saniertes Wohngebäude

The ProRetro project team held four focus groups in September and October 2021. Their goal was to discuss the business models that were developed in the first year of the project with potential customers and thereby learn how the concepts are received. The implementing partners invited potential customers to participate in the virtual group interviews. The predominantly positive feedback confirms the project’s approach. However, queries also showed that some questions remain to be addressed.

A focus group is a qualitative research method during which the knowledge and opinion of group participants are queried in a systematic manner. A guideline with a number of open-ended questions helped to structure the discussions. The answers to these questions will help the implementing partners to improve their business models.

Predominantly positive feedback on the project’s approach

Many participants find the idea of being able to obtain an energy efficiency renovation from a single source very attractive. Being able to save time and the access to experience and know-how are the main reasons given for this assessment. Knowledge of contractors that are specialised on energy efficiency renovations and not having to search qualified companies, expertise and information on subsidies are additional motives.

Especially in the case of condiminiums a one-stop-shop like the one planned for the district of Böblingen can lower hurdles on the way to an energy efficiency renovation.

At the same time, energy efficiency renovations are most challenging in the case of condominiums: Homeowner communities are sometimes required to obtain quotations from at least three different contractors and compare those. A one-stop-shop business model aiming at homeowner communities must accomodate this fact.

Other concerns when it comes to commissioning a one-stop-shop are related to questions of liability and warranty. The ProRetro one-stop-shops differ in how they deal with this question. While the business model of Raumfabrik from Wuppertal includes construction management and construction works are mainly performed by Raumfabrik’s shareholders, the one-stop-shops from other project regions only inform about possible contractors. These are then responsible for the quality of works.

Willingness to pay for the one-stop-shop’s service is high among owner-occupiers of single-family homes. They expect to save a lot of time when commissioning a one-stop-shop. Members of homeowner communities had differing opinions in this regard. In any case, possible subsidies have to be taken into account.

Additional ideas for the ProRetro one-stop-shops


Many participants would find a list of best practice examples (including a picture gallery and information on costs) on the homepages of the implementing partners helpful. This would give a first impression of how expensive different types of energy efficiency renovations could be. Participants also desire an overview and self-presentation of eligible contractors. In general, participants recommend to present detailed, but easily understandable, information on the one-stop-shop’s website.

One idea to achieve this is to embed short explanatory videos (e.g., on the one-stop-shop’s approach). A number of participants also suggested to integrate a contact form that names the responsible contact person and shows a picture of her or him. In conclusion, this demonstrates that the implementing partners received numerous ideas on how to improve their business model and marketing.


Disseminate information

Participants were also asked through which channels they want to be informed about the one-stop-shop or which channels they would use to actively look for information. Their answers help to develop ways to make the one-stop-shop more well known.

The discussions have shown that participants assess print products like flyers differently. Some consider them as quickly becoming outdated and unnecessary, while others find them practical. One task for the future will be to analyse the local demand for these marketing products individually for each region. Online newsletters were also assessed contrastingly: While some participants welcome regular information that also serves as a reminder, a majority of participants see them as to infrequent and inadequate.

In general, a majority of participants want a clear and detailed website with information about the their region’s one-stop-shop. The focus group participants also recommended to involve the organsations in the one-stop-shop’s network in advertising the service. According to the participants, certain groups like citizens that have just moved to the city or region should be informed about the local one-stop-shop for energy efficiency renovations by the municipality.

Some questions remain open

All in all, the focus groups have demonstrated that there seems to be great interest in and a need for a one-stop-shop’s service. Nevertheless, legal frameworks and funding conditions have to be studied in more detail during the trial phase. The relationship with self-employed energy advisers, who at least in part offer comparable services, also has to be examined. Certainly, creating parallel structures should be avoided. The question whether the one-stop-shop could already be involved before making the decision whether to buy a certain house or not reveals that there is demand for such services. At the same time, this also shows the challenge of one-stop-shops having to meet very diverse demands.