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Prefabricated houses, Mobile homes


In January of 2016, the Center for Public Service (CPS) was approached by Energy Trust of Oregon to conduct a review of the tax assessor data on manufactured houses in Oregon. The purpose of this review was to find the average age at which manufactured housing units in Oregon are decommissioned. A brief review of the literature on this topic that has been published indicated that this question had not yet been answered in the field.

Energy Trust Oregon is invested in making manufactured housing living more energy efficient, and less costly for occupants. To that end, the organization designed this investigation into the relative savings of replacing an inefficient unit today, versus waiting for the unit to be decommissioned in the future. The organization believes that they can demonstrate that it is both environmentally sustainable relating to energy usage and economically prudent to support a program that aims to swap out old, inefficient units for new, sustainable ones.

Work on this project began in March 2016, and was conducted by a group of CPS researchers (CPS Research Team). Details about the team members are included at the end of this report.

The CPS Research Team considered this project in three parts: case identification, data collection, and data analysis. These efforts are detailed below. Our analysis included over 600,000 tax records. We identified over 6,500 tax accounts that were closed during the period of analysis. The average age of manufactured housing unit at the time of tax account closure – across all counties and years considered – was found to be 33.36.

Persistent Identifier

energy trust_projectbrief.pdf (151 kB)
Project Brief