Vernacular Timber-Framed Church Steeples

NCPTT Grant # MT-2210-06-NC-09

Project Title: Vernacular Wooden Church Steeples in the Eastern United States: Form and Restoration

Organization: Timber Framers Guild

Principal Investigator: Jan Lewandoski

Project Team: Jack Sobon, Ken Rower, Ed Levin, Dave Fischetti

Grantee contact: Will Beemer

Date of Final Report: September 24, 2008

Executive Summary

As of September 24, 2008, five monographs related to the form and restoration of historic wooden steeples have been published under this grant in Timber Framing, the quarterly journal of the Timber Framers Guild. The five monographs include:

Middleburv. Vermont by Jan Lewandoski. March 2007, Timber Framing No. 83.
Restoration Strategies by Jan Lewandoski. September 2007, Timber Framing No. 85
Masts and Telescoping by Jan Lewandoski. December 2007, Timber Framing No. 86.
Reproducing Burned or Destroyed Steeples by Jan Lewandoski. March 2008, Timber Framing No. 87.
Engineering a Steeple Restoration by David Fischetti. September 2008, Timber Framing No. 89

This project provides not only explication of steeple form and structure, but also guidance for repair and restoration. Until now there were no written sources available on the structure, technology, and repair of American wooden church steeples.

Principle investigators included Jan Lewandoski, author and timber frame specialist who has supervised the reconstruction of many historic churches, meetinghouses, and covered bridges in the US. Dave Fischetti, a principal of DCF Engineering, and Ed Levin, architectural and structural designer, and consultant, provided structural analysis. Drawings were provided by Mr. Fischetti and by architect, author, and timber framer Jack Sobon. All are members of the Timber Framers Guild, which publishes Timber Framing, the quarterly journal where the monographs first appeared. Editor Ken Rower completed the Project Team by assisting in the research and production of the monographs.

The scope of the original grant changed slightly when it became apparent that the investigation of 17 steeples as originally proposed was not needed to gather the data required. Thus, fewer steeples were visited but more detailed investigation and time was spent at each one.

The computer modeling required to analyze a 3-dimensional structure like a steeple proved much more difficult than the simpler 2-D analysis originally envisioned. Once the researchers got in the steeples and realized how they behaved structurally, they saw that the analysis required to cover the subject adequately was beyond the scope of this grant. Instead, we decided to add a nationally recognized structural timber engineer (David Fischetti) to the team to describe the engineering strategy and evaluation undertaken in the restoration of one notable steeple project. In this fifth monograph Mr. Fischetti also notes some general recommendations for engineering analysis and repairs on other steeples, which we feel adequately served our need to address the topic in this series.The series of monographs is available for downloading at no charge from the Timber Framers Guild website at www.tfguild.org.

Methods and Results

The investigation team visited numerous steeples in the Eastern United States to analyze their form and structure, identify common features, erection techniques and problems that lead to deterioration and the need for repair. They also developed restoration strategies, including dismantling and re-erection.

This methodology required climbing into dark, dirty, crowded spaces often accompanied by the detritus of various forms of wildlife. Through careful measurement and photographs they were able to produce detailed drawings (mostly sections) showing the various stages and levels typical in steeple construction.

The first monograph, titled Middlebury. Vermont, focused on one of the most substantia l and sophisticated of all US steeples, Middlebury 's Congregational Church (1806-09). This frame was used to illustrate some of the basic principles of steeple construction, such as the structural foundation, crabs, partners, telescoping frames, towers, belfries, clock stage, lanterns, and spires. Exploded views of timber joinery help illustrate the method of erection.

In the second article, Restoration Strategies. the South Woodstock (Vermont) Community Church (1839) and the Strafford (Vermont) Meeting House (1799) were studied and used to describe some common problems with older steeples caused by water infiltration, wind loading, and structural inadequacies. The keys to successful evaluation, access, scaffolding, dismantling, restoration and re­ erection are also explained.

The third installment, Masts and Telescoping, focused on the Castleton (Vermont) Federated Church (1832), the Stowe (Vermont) Community Church (1861) and Philadelphia's Christ Church (1754). The researchers here described in more detail the structural intricacies of the framing, the inventiveness of the builders in figuring out how to erect them, and the ways the significant loads are transferred through the nested frameworks.

In monograph four, Reproducing Burned or Destroyed Steeples, principle investigator Jan Lewandoski revisits the problems associated with wind, water, and structural inadequacy and typical ways to resist them, and then describes the strategy to reproduce a steeple destroyed by another typical failure mechanism: lighting-induced fire. Keeping the burned pieces and examining photographs, documentary evidence and similar examples can provide clues to the original form.

The last of the series is Engineering a Steeple Restoration. Here engineer David Fischetti describes the strategy for a computer-generated engineering analysis (both 2-dimensional and 3-d) of a steeple and uses St. Michael's Episcopal Church (1752- 61) in Charleston, South Carolina as an example. Such a detailed analysis of one frame may not yield results applicable to other steeples; each is unique and should be properly analyzed on its own. But the strategy described here provides insight on how such an analysis is done.

Future Projects

The publications of the five monographs produced by this grant have already aroused interest throughout the preservation and timber framing communities. We have a proposal for a sixth article for Timber Framing from a professional engineer focusing on the steeple of Independence Hall in Philadelphia. Eventually we would like to combine all of these articles and any future ones into a single volume.

Conclusion

This study provides better understanding of the form and dynamics of the thousands of American wooden steeples from the 18th and 19th centuries standing today. It is a valuable resource and guide to the architects, engineers, contractors, and preservation specialists responsible for these iconic public monuments that are the centerpiece of so many townscapes.

A series of articles related to the form and restoration of historic wooden steeples in the Eastern United States.