Residential Building Envelope Energy Retrofit Methods, Simulation Tools, and Example Projects: A Review of the Literature

Abstract

As one of the biggest energy consumers, buildings are the focus of the energy conservation market, and the building envelope, which has the highest impact on heating and cooling loads, is one of the main targets in retrofit projects. Several materials, systems, methods, and simulation tools are used in these projects, and it is critical to understand the impact of these methods in different locations, their frequency of use, and the effectiveness of market-ready new solutions. In that context, it is necessary to review the energy conservation measures (ECMs) that are suitable for residential building envelope retrofitting, and that are commercially available or under research and development. This paper provides an overview of these ECMs. A literature review was conducted on different building envelope ECMs, including traditional and innovative energy retrofit methods, such as aerogel and phase change materials on opaque and transparent components of existing buildings. Results show that the most effective retrofit projects include bundles of ECMs, and the traditional ECMs can be as effective as more innovative solutions in terms of energy saving. Moreover, computer energy models were created for a typical residential building in the US for cold and warm climate zones to determine the impact of different retrofit approaches based on a sensitivity analysis. Results show that envelope ECMs have higher energy saving potentials in cold climate zones, of up to around 30%, and reducing the air infiltration has the highest impact in both cold and warm climate zones in a typical small residential building.