Need for Systematic Retrofit Analysis in Multifamily Buildings
Multifamily housing offers high potential for energy savings through retrofits. A comprehensive energy audit with systematic evaluation of alternative energy measures is one of the key steps to realizing the full energy savings potential. However, this potential often remains unrealized when the selection of measures is (1) based on a one-size-fits-all approach originating from accustomed practices, (2) intended merely to meet code-compliance requirements, and/or (3) influenced by owner renter split incentive. In such cases, the benefits of comprehensive energy auditing are disregarded in view of the apparent difficulty in diagnosing multifamily buildings, evaluating alternative measures, and installing customized sets of measures. This paper highlights some of the barriers encountered in a multifamily housing retrofit project in Georgia and demonstrates the merits of systematic retrofit analysis by identifying opportunities for higher energy savings and improved comfort and indoor air quality that were missed in this project. The study uses a whole-building energy analysis conducted for a 10-unit, low-rise, multifamily building of a 110-unit apartment complex. The analysis projected a 24% energy savings from the measures installed in the building with a payback period of 10 years. Further analysis with a systematic evaluation of alternative measures showed that without compromising on the objectives of durability, livability, and appearance of the building, energy savings of up to 34% were achievable with a payback period of 7 years. The paper concludes by outlining recommendations that may benefit future retrofit projects by improving the audit process, streamlining tasks, and achieving higher energy savings.