After nine months of work, the installation of the new pre-cast façade for Six Logan Circle was completed at the cost of $225,000, or slightly less than one-forth of the total project cost. The project was considered a success by all the participants; the stated goal of removing the crumbling serpentine veneer and replacing it with a new material that returned the façade to its original appearance was met. The building has a renewed presence with its pre-cast concrete units molded to match the form of the original detail, texture and color that had been absent for many years (see figure 12).

Some of the trim pieces, in particular the floral blocks as well as units in the belt coursing and window sills, do have noticeable surface imperfections when viewed up close, such as indentations caused by air bubbles and in a few instances the aggregate is exposed, indicating a poor concrete mix. Ideally, each of these units should have been rejected during the inspection state. However, the small number of such pieces does not detract from the overall appearance of the rebuilt façade.

The manufacture and installation of the new pre-cast concrete units and historic brick was an expensive undertaking; however, in this case, alternative options were very limited. The new owners chose this course of action because of their desire to find a long lasting solution to a difficult problem. This approach may not be appropriate in all situations involving deteriorated serpentine or other types of historic masonry. Total replacement of the deteriorated stone veneer of a historic building using a substitute material should be considered only after careful analysis. If, after a thorough examination of all possible alternative treatments, a replacement approach is selected, the project should be undertaken only by qualified personnel under professional guidance and supervision.

Figure 12. The house before and after rehabilitation. Photos: Anne Grimmer and Liz Creveling.

PROJECT DATA:

This PRESERVATION TECH NOTE was prepared by the National Park Service. Charles E. Fisher, Heritage Preservation Services, National Park Service, serves as the Technical Editor for the PRESERVATION TECH NOTES. Information on the cast-stone replacement system described here was supplied by James F. Smith, General Partner and Contractor for the project, and Gary R. Brenner and Seymour Lewin, project consultants. Special thanks to the following National Park Service staff who contributed to the production of this Tech Note: Martha Raymond, Dennis Montagna and Varnetta Ross of the Mid-Atlantic Regional Office, and Anne Grimmer, Theresa Robinson and Brenda Siler of the Preservation Assistance Division. Cover Photo: Six Logan Circle after rehabilitation.

PRESERVATION TECH NOTES are designed to provide practical information on innovative techniques and practices for successfully maintaining and preserving cultural resources. All techniques and practices described herein conform to established National Park Service policies, procedures, and standards. This Tech Note was prepared pursuant to the National Historic Preservation Act which direct the Secretary of the Interior to develop and make available to government agencies and individuals information concerning professional methods and techniques for the preservation of historic properties.

Comments on the usefulness of this information are welcomed and should be addressed to PRESERVATION TECH NOTES, Technical Preservation Services, National Center for Cultural Resources, National Park Service, 1849 C Street, NW, (2255) Washington, DC 20240.

This publication is not copyrighted and can be reproduced without penalty. Normal procedures for credit to the author and the National Park Service are appreciated.