Imagine you own an apartment building and want to insulate it or install better heating — but your tenants pay the energy bills, not you. So why would you spend the money? RentalCal built an online calculator that finally shows landlords and investors whether an energy upgrade will actually pay off, factoring in each country's rent laws, tax rules, and green property value premiums. It covers 8 European countries so investors can compare where their money works hardest.
Property investors in the rental sector lack reliable tools to assess whether energy efficiency upgrades will be profitable. The landlord pays for the retrofit but the tenant benefits from lower energy bills — a classic "split incentive" problem. Existing calculation methods were designed for owner-occupiers and ignore rental-specific factors like rent regulations, tax regimes, and green value premiums in each national market.
The project delivered a public online calculation and information platform that lets rental property investors assess the commercial viability of energy retrofits across 8 EU member states. In total, 32 deliverables were produced including the standardised assessment methodology, country-specific investment condition data, and target-group-specific information materials.
If you are a residential real estate fund evaluating energy upgrades across your European rental portfolio — this project developed a standardised profitability calculator covering 8 EU countries that factors in local rent regulations, tax regimes, and green value premiums. It lets you compare retrofit ROI across markets before committing capital.
If you are a property management company advising landlords on whether to invest in better insulation or heating — this project built a publicly available online platform that calculates the financial return on energy retrofits specifically for rental properties. It accounts for the split incentive problem where landlords pay but tenants benefit from lower bills.
If you are an energy efficiency consultancy that needs to make the business case for retrofitting rental buildings — this project created an assessment methodology tested across 8 member states with 11 consortium partners. The online tool gives you country-specific data on investment conditions, helping you build credible financial proposals for landlord clients.
The online calculation and information platform was set up as a public website (rentalcal.eu) as part of an EU-funded Coordination and Support Action. Based on available project data, the tool was designed for public access to increase market transparency.
The tool was designed to cover 8 EU member states (CZ, DE, DK, ES, FR, NL, PL, UK) with a standardised methodology that allows transparent comparison of investment conditions. It was built for cross-border investment analysis, making it suitable for portfolios spanning multiple markets.
The project was funded as a CSA (Coordination and Support Action) with 11 partners across 8 countries. The coordinator is Institut Wohnen und Umwelt GmbH in Germany. Based on available project data, the methodology and platform were developed for public benefit, but specific IP arrangements would need to be confirmed with the coordinator.
Yes — a core feature is that the calculation methodology incorporates country-specific legal, technical, and financial conditions including rental regulations, tax regimes, and split incentive structures. This was developed for all 8 participating member states.
The project closed in July 2018. Based on available project data, there is no information on post-project maintenance or updates. The website rentalcal.eu was the main platform, but current availability should be verified directly.
The project specifically researched and integrated valuation benefits of energy-efficient buildings into its profitability calculations. This includes both direct financial returns and indirect benefits like increased property value — what the project calls the 'Green Value' proposition for rental investors.
The consortium of 11 partners across 8 countries provides genuine pan-European coverage for this rental market tool. With 5 universities providing research depth and 3 industry partners (27% industry ratio) including 3 SMEs, the project balanced academic rigour with market relevance. The geographic spread — Czech Republic, Germany, Denmark, Spain, France, Netherlands, Poland, and the UK — captures diverse rental market conditions from heavily regulated (Germany, Netherlands) to more liberal markets. The coordinator, Institut Wohnen und Umwelt GmbH in Germany, is a housing and environment research institute, well-positioned to lead a rental-focused initiative.
Institut Wohnen und Umwelt GmbH (Germany) — contact details can be found via the project website or CORDIS page
Want to connect with the team behind this rental retrofitting calculator? SciTransfer can arrange an introduction to discuss licensing the methodology or adapting it for your market.
