This paper reviews empirical data from evaluations of the influence of residential energy efficiency retrofits on indoor environmental quality conditions and self-reported thermal comfort and health. Data were extracted from 36 studies described in 44 papers plus two reports. Nearly all reviewed studies were performed in Europe or United States. Most studies evaluated retrofits of homes with low-income occupants. Indoor radon and formaldehyde concentrations tended to increase after retrofits that did not add whole-house mechanical ventilation.

The economics of energy efficiency programmes have been subject to considerable academic debate lasting well over three decades now. In this paper, we contribute to this debate by reviewing the costs and benefits of a specific type of policy+ instrument that recently gained significant traction in Europe – Energy Efficiency Obligations - EEOs. Following the introduction of the EU Energy Efficiency Directive in 2012 the number of EEOs in Europe has grown from five schemes to now 16 EEOs in operation or planned across the EU.