December 19, 2008

Abstract: 

Following the almost complete destruction of Greensburg, Kansas by a tornado in May, 2007, Building Science Corporation (BSC) was contracted to provide example house plans, support for the reconstruction of energy efficient houses and training for builders and trades. This report describes the results of BSC’s work to construct more than 20 energy efficient, affordable, durable houses in Greensburg, Kansas. Twenty houses have been constructed meeting greater than 40 percent whole-house energy savings compared to the BA Benchmark. The approach demonstrated performance benefits and cost savings such that the development group (Mennonite Housing) has adopted the technology for all of their projects in Kansas.

Executive Summary

1. Overview

Following the initial emergency response to the destruction of Greensburg, Kansas by a direct hit by a massive tornado, the Department of Energy joined other federal agencies, including FEMA and the EPA, in providing long-term recovery support for Greensburg residents. The DOE's effort included support for power generation and distribution planning, advice for energy efficient building construction, and assistance for builders and homeowners.

Building Science Corporation (BSC), a research team working with DOE's Building America program, was contracted to provide example house plans, support for the reconstruction of energy efficient houses and training for builders and trades. This report describes the results of BSC's work to construct more than 20 energy efficient, affordable, durable houses in Greensburg, Kansas.

2. Key Results

Twenty houses have been constructed meeting greater than 40 percent whole-house energy savings compared to the BA Benchmark. The approach demonstrated performance benefits and cost savings such that the development group (Mennonite Housing) has adopted the technology for all of their projects in Kansas.

3. Next Steps

Testing and monitoring of the constructed homes will be completed by NREL.

1. Introduction

1.1 Task Description

This task provides technical support for energy efficient reconstruction of the residential areas affected in the aftermath of the recent natural disaster in Greensburg, Kansas. In coordination with NREL, the Subcontractor shall develop plans and other documents in support of the construction of new energy-efficient homes in this region. The subcontractor shall develop one example set of floor plans, and provide technical support for communications materials being prepared by NREL for upcoming events in Greensburg. In addition, five sets of standardized construction documents (adapted to various foundation types and lot characteristics) shall be developed for the community, and additional direct technical assistance shall be provided to ten residents or builders that act as early adopters of the standard floor plans. The subcontractor shall also develop and distribute overview booklets describing the energy efficiency features of the proposed plans, design and construct a sample wall section to illustrate the recommended building techniques, and conduct eight half-day training sessions in Greensburg to teach local builders and contractors about advanced energy efficient construction techniques, foundation details, and mechanical and electrical system details.

Deliverable:

Working with lead builders and homebuyers in Greensburg, the Subcontractor shall report on ten projects, derived from five standard floor plans, that are expected to achieve at least 30% wholehouse energy savings compared to the BA Benchmark. The report shall include:

  • projected whole-house source energy savings compared to the BA Benchmark and regional standard practice.
  • initial estimates for increases in retail costs required to achieve targeted energy savings levels as a function of individual system performance upgrades and improvements.
  • plans for quality control tests and energy performance measurements.
  • a description of expected technical barriers that may limit adoption of advanced systems to be tested by the project.
  • recommendations for optimum construction and delivery processes and infrastructure requirements to successfully build advanced buildings.

1.2 Background

On May 4, 2007, the city of Greensburg, Kansas was almost completely destroyed by a large tornado.1

Following the initial emergency response, the Department of Energy joined other federal agencies, including FEMA and the EPA, in providing long-term recovery support for Greensburg residents. The DOE’s effort included support for power generation and distribution planning, advice for energy efficient building construction, and assistance for builders and homeowners.

Figure 1.1: Aerial photograph of tornado damage at Greensburg, KS (source: Jaime Oppenheimer/The Wichita Eagle

Building Science Corporation (BSC), a research team working with DOE’s Building America program, was contracted to provide example house plans, support for the reconstruction of energy efficient houses and training for builders and trades.

This report describes the results of BSC’s work to construct more than 20 energy efficient, affordable, durable houses in Greensburg, Kansas.

2. Technology Package for Greensburg, KS

2.1 Technology Package Summary

The technology package recommended for Greensburg, Kansas was based on previous work by Building Science Corporation in the Mixed-Humid climate. Our recommendation was also tailored to provide a package that could be justified within the expected construction budget for rebuilding a house in Greensburg. The additional capital cost was shown to be fully offset by the energy savings predicted by our energy analysis (see Section 2.2 below). To further reduce the upfront cost, BSC arranged an incentive program for the first 10 houses built to this specification (see Section 3 below).

Table 2.1 and Figure 2.1 below show the characteristics for both the base case house for comparison and the BSC recommendation. . .

Download complete report here.

Footnotes:

  1. r more information on the Greensburg tornado event, see http://en.wikipedia.org/wiki/Greensburg,_Kansas