One-stop shopping for renovation

This thesis presents an ideal concept for implementing a one-stop shopping concept whereby a single actor offers a full-service renovation package. The purpose of such a one-stop shop is to help house owners with the design and decision-making process in connection with renovation of their house.

5.3.1 Implementation of the ideal concept

The implementation of the ideal one-stop shop concept should make it easy, simple and secure for the house owner to invest in a low-energy renovation. Following the concept, house owners will get a quality renovated house with little risk and responsibility. For a successful implementation of the proposed concept, however, it is essential for the service provider to understand the house owners’ needs and wishes.

For example, in Step 2 of the ideal concept, the house owner is provided with an evaluation report based on extensive analysis of the condition of the house. This report should include an estimation of the potential energy savings and economic implications for the holistic renovation needed. In some cases, the house owner may not have the means for a holistic renovation, so the company should also offer to make a detailed long-term plan for renovation, which optimizes the economic aspects in relation to the house owner’s wishes and needs. Furthermore, the traditional market for renovation is very much a do-it-yourself-culture; so the renovation packages proposed should be flexible to handle a house owner’s wish to contribute to the process of carrying out the work.

Business model and marketing strategies

Other aspects of successful implementation of the ideal concept are marketing and business strategies. Haavik et al (2010) identified that various types of actors, such as hardware supply chains, utility companies and contractors, could play the key role in a one-stop shop for the energy-efficient renovation of single-family houses. The service might also be provided by an existing company that wants to expand its business.

From evaluation of the few existing one-stop shop models, Mahapatra et al. (2013) found that it is difficult to run such a business and identified the main barrier from the house owner’s point of view to be the trustworthiness of the service provider and all the actors involved in the one-stop shop. This is because the service is new and may be perceived as risky by house owners. To improve trustworthiness, the service provider needs to be able to offer independent but quality advice to the house owner.

Collaboration with well reputed research organizations or public bodies and the training of installers/sellers could also help build trust.

Furthermore, uncertainty about the level of energy savings after renovation due to varying occupant behaviour might discourage both the house owner and financiers from making energy-efficient investments. However, there are concepts for guarantees on energy savings for industrial and public buildings (the ESCO concept), which may also emerge for residential buildings. Alternatively, information campaigns and the availability of policy instruments in form of regulations and economic incentives may create house owner interest in energy-efficient renovations (Mahapatra et al. 2013). Another way is to provide public funding for demonstration projects. The ideal concept for a one-stop shop business model is currently being tested for the holistic renovation of two Danish single-family houses built in the period 1960-1970. Important experience will be gained from this, and the dissemination of results from these demonstration projects may contribute to a larger market for energy-efficient renovation.

5.3.2 Technical renovation packages targeted at single-family houses As part of the ideal concept proposed in this thesis, renovation packages targeted at various types of Danish single-family houses were suggested and investigated in two case studies. Results from the case studies showed that both typical single-family houses could be renovated to a level of energy performance which is comparable to the requirements for new houses today. However, to reach this target, what is needed is a complete energy-efficient renovation with extensive post-insulation and sealing of the building envelope, the installation of a mechanical ventilation system with high efficiency heat recovery and low electricity use, and an energy-efficient heating system (renovation package 5). To renovate the case studies to the level that meets requirements for future buildings, it was found that more ambitious measures (better insulation materials and new components) or an additional supply from renewable energy would be needed, irrespective the building typology.

Cost‐efficiency of measures

Carrying out a comprehensive low-energy renovation means a relatively large investment. The total investment needed to reach a low primary energy level and a good indoor environment after renovation has been calculated to be in the range of EUR 100,000 (DKK 750,000). Results from cost calculations have showed that if packages of technical energy efficiency measures are to be attractive for the homeowner, it is generally crucial to link them to normal renovation measures needed due to physical degradation of major building components, bad indoor environment or/and health problems. In this way, costs are not compared to energy benefits alone.

These cost calculations were based on the criterion of cost of conserved energy (CCE). Mahapatra et al. (2011) suggested that the method of “annual economic balance”, i.e. savings minus repayments on a mortgage credit loan could also be used because this might be relevant for house owners who want to utilize cheap long-term financing based on equity. Moreover, it is also important to address the non-energy benefits of energy-efficient renovation, such as better and healthier indoor environment and comfort. Other benefits are the improved lifespan of structures, the increase in the value of the house, and less dependence on expected future higher energy prices.