Student research results - Tile removal and other climate adaptation measures for households

Our MSc student Niels Evers finished his thesis last month on "The effectiveness of municipal climate adaptation policy instruments for households". He compared the measures taken in six different municipalities: Almelo, Enschede, Hardenberg, Hellendoorn, Winterswijk, and Zwolle. These measures are meant to stimulate citizens to have a more climate adaptive garden/house and cover tile removal, a green coach, and subsidies for e.g. green roofs or rain barrels. The main question concerns how often these measures are used by citizens. One result was the number of tiles removed, as seen in the image below. This number did include tiles that the municipalities removed that were on their own managed terrain, so sometimes the numbers were skewed. The thesis summary is below, and the repository link to download the full thesis is here. 

 

Summary:

To achieve the goals for climate adaptation set by the National Delta Program (Ministerie van Infrastructuur en Waterstaat et al., 2024), municipalities are dependent on households taking action. More than 50% of the surface in urban areas is privately owned (’t salland, 2024). And together with public areas, this land is needed for measures. Municipalities use policy instruments to encourage households to take action. For this reason, 60% of the Dutch municipalities have a subsidy scheme for climate adaptation measures (Centraal Beheer, 2025). Around the same number of municipalities participated in an campaign to remove as much tiles as possible and replace it with green. Last year, 5,5 million tiles were removed in this NK Tegelwippen competition (NK Tegelwippen, n.d.).
The experience about how to encourage households has been increasing over the last years, however, the municipalities would like to improve the effectiveness of their policy instruments. Policy instruments are tools that the municipalities use to influence the behaviour of households. In this research, the instruments aim to encourage households to take action to adapt to climate change. There have been multiple studies on the conceptual level explaining how an instrument could be more effective. There is not a lot of research done on policy instruments for climate change adaptation from municipalities to households. The research that has been done on this topic is often limited to one instrument or instrument type and uses mostly qualitative data. There has not been research on the combination of the different policy instrument types and also not with a quantitative view. The research question is: “How effective are municipal climate adaptation policy instruments for households, both individually and in the policy mix?”
Policy instruments cannot be seen as separate elements, but should rather be seen in a policy mix, consisting out of the entire set of policy instruments. Four types of instruments are distinguished: communication, economic, regulation and distributive. Communication refers to all sorts of information streams from the municipalities to the households, like education, knowledge exchange and foresighting (Hannon et al., 2023). The economic instrument type refers to incentives or disincentives (Hannon et al., 2023), this can be in the form of subsidies or taxes for example. Next to that, there is regulation, which is about rules and laws (Hannon et al., 2023). This is for instance used in the building law for new buildings to retain water on own property. Lastly, the distributive instrument type provides a service or good to remove barriers for households (Martin et al., 2021).
This study looks into three policy instruments that are commonly applied by municipalities to encourage households to take action: NK Tegelwippen, the subsidy scheme and green coaches. This study seeks to understand how they are best applied to achieve the biggest impact and, therefore, are most effective. Effectiveness can encompass many different things. In this study, the more applications and households participating in an instrument, the more effective. A comparative case study analysis is used, consisting of six municipalities: Almelo, Enschede, Hardenberg, Hellendoorn, Winterswijk & Zwolle. Those municipalities were selected based on that they should have similar climate adaptation challenges, have different policy mixes and be different in size. This study combines both quantitative and qualitative data. The qualitative data was collected using policy papers, websites and interviews with civil servants of the municipalities. The quantitative data directly showed the number of households making use of the instrument or the impact that those households made (e.g. number of removed tiles). The number of removed tiles per 1000 inhabitants for each municipality fluctuates over the years. The bigger municipalities, which also make use of a tile pick-up service, had the most removed tiles. Zwolle has the highest yearly average with around 900 removed tiles per 1000 inhabitants. During the interviews, it became clear that for some municipalities, over 50% of tiles are removed from public areas. This makes it difficult to make statements about the effectiveness of the instrument in encouraging households to take action.
The green coaches have only been active for one or two years at the selected municipalities. The number of applications is low, less than half a per cent of households made use of the green coaches. This is sometimes because it is not well known yet, but also because of the limited capacity of the green coaches. The impact of the green coaches is therefore difficult to measure. Each municipality offers different measures that are eligible for subsidies. All selected municipalities have subsidies for measures to prevent water nuisance. 4 out of 6 municipalities have a more integrated subsidy scheme and also make measures such as greening, trees or a green roof eligible.
By looking at the distribution of measures, it becomes clear that above 50% of the applications are done for rain barrels. During the interviews, it became clear that the NK Tegelwippen is part of a bigger instrument: ‘Targeted actions’. These actions are temporary and focused on concrete incentives. Next to the NK Tegelwippen, there are also examples of a tree sharing day (boomdeeldag) or a rain barrel action in which rain barrels can be bought for a reduced price.
This research shows that targeted actions are the most effective instrument for mobilising households to take climate adaptation measures, as they reach large groups quickly and can be tailored to specific neighbourhoods or climate-adaptive interventions. Their effectiveness arises from the combination of financial incentives, targeted communication, and distributive services, which together ensure both speed and inclusivity. In contrast, subsidy schemes reach fewer households and rely heavily on residents’ initiative, while physical sustainability hubs and online platforms are not effective as stand-alone instruments.
Green Coaches show strong potential, particularly when combined with targeted communication and modest financial incentives, as demonstrated by Winterswijk. Scaling these strategically could enhance participation among households that are typically harder to reach. Municipalities should therefore focus on instrument combinations that maximise reach, lower barriers, and address local climate challenges, while also improving standardised data collection and monitoring to generate actionable insights.
Overall, this thesis demonstrates that successful municipal climate adaptation policy is less about introducing new instruments and more about using existing ones in a coordinated, evidence-based way. Targeted actions set the benchmark, Green Coaches hold promise if scaled strategically, and subsidies should be re-evaluated to go beyond purely financial incentives. By combining insights from implementation, monitoring, and research, municipalities can develop more effective and equitable strategies to support households in adapting to climate change.