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Insulating Concrete Forms: Installed Cost and Acoustic Performance Dfgjk Insulating Concrete Forms: Installed Cost and Acoustic Performance US Department of Housing and Urban Development Office of Policy Development and Research Insulating Concrete Forms: Installed Cost and Acoustic Performance dfgjk Insulating Concrete Forms: Installed Cost and Acoustic Performance Prepared for: US Department of Housing and Urban Development, Portland Cement Association, and National Association of Home Builders Prepared by: NAHB Research Center, Inc. Upper Marlboro, MD December 1998 dfgjk Foreword As we near the end of the 1990s, we have reason to celebrate some of our successes in identifying and improving innovative materials that can help reduce our dependence on lumber and improve the building industry’s efforts to deliver affordable housing to our citizens. Throughout much of the decade, the U.S. Department of Housing and Urban Development has supported joint efforts with the Nation’s builders and manufacturers to accelerate the adoption of innovative materials for home construction. This includes efforts to improve the efficiency of lumber construction as well as researching alternatives such as cold-formed steel, panel construction, and insulating concrete form systems. Despite these initial successes, we realize that our work is just beginning. The President’s new initiative, The Partnership for Advancing Technology in Housing (PATH), will build more durable and resource-efficient homes. We look forward to that challenge and continue to work closely with industry to achieve our goals. Insulating concrete forms (ICFS) are an example of one of the technologies that the PATH program can capitalize on to improve our housing. This report contains results of one of our latest studies on this intriguing technology innovation. This report will allow builders to better evaluate the cost impacts of ICFs. It also identifies many opportunities to optimize the construction of homes using this technology. We hope you not only find this report valuable, but that you help us continue to improve these types of technologies by passing your experience and suggestions for improvements on to the many excellent manufacturers of these products. Xavier de Souza Briggs Deputy Assistant Secretary for Research, Evaluation, and Monitoring dfgjk Insulating Concrete Forms: Installed Cost and Acoustic Performance Acknowledgments The NAHB Research Center Inc., located in Prince George's County, MD, was established in 1964 as a separately incorporated, wholly-owned, not-for-profit subsidiary of the National Association of Home Builders (NAHB), whose 197,000 members are involved in the construction of over 80% of U.S. homes. The Research Center studies all aspects of home building, tests and certifies building products in a fully equipped laboratory, and conducts a wide range of dissemination and training activities for builders, remodelors, and other participants in the housing industry. Our research is sponsored by NAHB, public agencies, and private-sector clients. This report was prepared by the NAHB Research Center for the Portland Cement Association, National Association of Home Builders and the U.S. Department of Housing and Urban Development. Product donations were provided by Reddi-Form, Lite-Form, and Owens Corning. The homes studied in this work were constructed by Romak & Associates of Chestertown, Maryland. Sound transmission tests were completed by Hessler Associates, Inc. of Cabin John, Maryland. Notice The U.S. Government does not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the object of this report. The contents of this report are the views of the contractor and do not necessarily reflect the views or policies of the U.S. Department of Housing and Urban Development or the U.S. Government. i dfgjk Insulating Concrete Forms: Installed Cost and Acoustic Performance TABLE OF CONTENTS TABLES AND FIGURES ........................................................................................................... iv EXECUTIVE SUMMARY .......................................................................................................... v INTRODUCTION AND SCOPE................................................................................................. 1 Insulated Concrete Forms ........................................................................................................1 DESCRIPTION OF HOMES ...................................................................................................... 3 APPROACH.................................................................................................................................. 5 Installed Time........................................................................................................................... 5 Labor Costs .............................................................................................................................. 5 Materials................................................................................................................................... 6 Sound Tests .............................................................................................................................. 6 Energy and Thermal Tests........................................................................................................6 FINDINGS: LABOR AND COSTS............................................................................................ 6 Labor Hours and Costs............................................................................................................. 7 Material Costs .......................................................................................................................... 7 Total Labor and Material Costs................................................................................................ 8 Labor and Cost Observations ................................................................................................... 9 FINDINGS: SOUND TESTS .................................................................................................... 10 ENERGY AND THERMAL PERFORMANCE...................................................................... 12 CONCLUSIONS AND RECOMMENDATIONS.................................................................... 12 APPENDIX A - DETAILED LABOR DATA APPENDIX B - DETAILED MATERIAL COST DATA APPENDIX C – EXCERPT FROM SOUND CONTRACTORS REPORT iii Insulating Concrete Forms: Installed Cost and Acoustic Performance TABLES AND FIGURES TABLES Table A - Total Productive Labor Hours by House Type and Component .....................................7 Table B - Labor cost by House Type and Component.....................................................................7 Table C - Material Costs by House Type and Component ..............................................................7 Table D - Total Labor and Material Cost by House Type and Component.....................................8 Table E - FSTC Ratings.................................................................................................................10 FIGURES Figure 1 – ICF Wall System Types..................................................................................................2 Figure 2 - Floor Plan of Test Homes ...............................................................................................3 Figure 3 - Reddi-Form System ........................................................................................................3 Figure 4 - Lite-Form System............................................................................................................3 Figure 5 - CMU Foundation Wall....................................................................................................3 Figure 6 - Location Map ..................................................................................................................4 Figure 7 - Site Plat ...........................................................................................................................4 Figure 8 - View of Completed Homes.............................................................................................5 Figure 9 - Vinyl Siding on Reddi-Form House ...............................................................................9 Figure 10 - Comparison of Average Transmission Loss ...............................................................11 Figure 11 - Reddi-Form Wall with Multiple Windows .................................................................11 iv Insulating Concrete Forms: Installed Cost and Acoustic Performance EXECUTIVE SUMMARY The NAHB Research Center conducted a study to compare the cost and performance of Insulating Concrete Form (ICF) walls to conventional wood-frame exterior walls. This report contains results on the cost study and sound transmission tests. The project is continuing through the spring of 1999 in order to monitor energy use over an extended period of time. Three homes were built and monitored. One home has an ICF plank system, one has an ICF block system, and one is of conventional 2x4 lumber construction. The homes have identical floor plans. They are located side-by-side on the same street in Chestertown, Maryland. Findings indicate that the labor cost for the ICFs were slightly to moderately higher than for the wood framing. Total installed costs however, averaged over $3000 more for the 1098 square foot single story ICF homes, or roughly $2.73 per square foot of floor area more than the wood frame home. This
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