The main aim of valuation is to take into account all of a property’s features relevant to its valuation. Alongside the cash flows and property risks, this includes the building characteristics, the quality of the location and environment, the impact of the property on society (e.g., creating jobs, improving quality of life) and its economic sustainability (e.g., climate-related risks and resource depletion). Hence, the appraiser has to include a wide range of relevant characteristics and needs to ensure there is no double-counting resulting from the non-transparent inclusion of sustainability criteria, as can occur in the additive method. The solution to this is the integrative approach. In this method, alongside the technical characteristics included in the additive approach, property characteristics in all three dimensions of sustainability (environmental, social, economic) with potential relevance to valuation are reviewed on a case-by-case basis using a longlist system (see NUWEL guidelines for further details). The appraiser can use this as a checklist to review whether a particular characteristic is appropriate and relevant to the valuation. This integrated list, which includes both characteristics relevant to sustainability (e.g., micro and macro location, plot, functionality, expected lifespan, etc.) and those not relevant to sustainability (e.g., resource use, health, functionality, lifespan, land consumption etc.), eliminates the differentiation between these characteristics and significantly reduces the risk of double-counting or non-inclusion.
In the discounted cash flow (DCF) valuation method, all criteria relevant to valuation, including the sustainability characteristics, are taken into account in the modeled cash flows. The presence or absence of sustainability characteristics (see previous section) is therefore monetized. For example, ESG-led measures such as the rental of roof space for solar panels can generate additional revenue that would not be available for a comparable property without solar panels. ESG-led costs can relate to renovating a property to make it more energy efficient and so reduce costs in the long term (e.g., lower energy costs through renewable energy sources, lower maintenance costs, lower repair costs through improved insulation and high-quality materials that avoid building defects and dampness, lower operating costs as there is usually less cleaning and maintenance work in energy-efficient buildings, and so on).
Only factors that cannot be included in the cash flows are incorporated as a property-specific risk in modeling the discount and capitalization interest rate. Figure 2 gives an overview of the sustainability criteria that can be integrated in the four value drivers of rental income, vacancies, operating and maintenance costs and the discount and capitalization interest rate. In concrete terms, this means that estimates of the annual gross yield of sustainable properties may assume rising rents (different growth rates and higher net payment capacity by tenants due to falling operating costs) and thus longer rental terms due to improved marketability and a smaller market. Life is healthier and more comfortable in energy-efficient buildings, which may be reflected in higher rents and tenant satisfaction. On the cost side, this means sinking operating costs (e.g., due to investments to improve the sustainability of a building during the investment period). The discount rate may also decrease due to the lower property-specific risk. The overall improved marketability of sustainable properties also means that a lower exit yield (higher property value, lower risk, potential for a long-term increase in value) will be reflected in the discounted cash flows.