Historic wooden shingle roofs

By Sharon C. Park, AIA

Introduction

Wooden shingle roofs are important elements of many historic buildings. The special visual qualities imparted by both the historic shingles and the installation patterns should be preserved when a wooden shingle roof is replaced.

On a wooden shingle roof, it is important not only to match the size, shape, texture, and configuration of historic shingles, but also to match the craftsmanship and details that characterize the historic roof. Proper installation and maintenance will extend the life of the new roof.

This requires an understanding of the size, shape, and detailing of the historic shingle and the method of fabrication and installation. These combined to create roofs expressive of particular architectural styles, which were often influenced by regional craft practices. The use of wooden shingles from the early settlement days to the present illustrates an extraordinary range of styles. Readily available and inexpensive sawn shingles were used not only for roofs, but for gables and wall surfaces.

Wooden shingle roofs need periodic replacement. They can last from 15 to over 60 years, but the shingles should be replaced before there is deterioration of other wooden components of the building. Appropriate replacement shingles are available, but careful research, design, specifications, and the selection of a skilled roofer are necessary to assure a job that will both preserve the appearance of the historic building and extend the useful life of the replacement roof.

Unfortunately, the wrong shingles are often selected or are installed in a manner incompatible with the appearance of the historic roof.

There are a number of reasons why the wrong shingles are selected for replacement roofs. They include:

• the failure to identify the appearance of the original shingles;
• unfamiliarity with available products;
• an inadequate budget;
• or a confusion in terminology.

In any discussion about historic roofing materials and practices, it is important to understand the historic definitions of terms like "shingles," as well as the modern definitions or use of those terms by craftsmen and the industry.

Historically, from the first buildings in America, these wooden roofing products were called shingles, regardless of whether they were the earliest handsplit or the later machine-sawn type. The term shake is a relatively recent one and today is used by the industry to distinguish the sawn products from the split products, but through most of our building history there has been no such distinction.

Considering the confusion among architects and others regarding these terms as they relate to the appearance of early roofs, it should be stated that there is a considerable body of documentary information about historic roofing practices and materials in this country, and that many actual specimens of historic shingles from various periods and places have been collected and preserved so that their historic appearances are well established. Essentially, the rustic looking shake that we see used so much today has little in common with the shingles that were used on most of our early buildings in America.

Throughout this brief, the term shingle will be used to refer to historic wooden roofs in general, whether split or sawn, and the term shake will be used only when it refers to a commercially available product.

This brief discusses what to look for in historic wooden shingle roofs and when to replace them. It discusses ways to select or modify modern products to duplicate the appearance of a historic roof, offers guidance on proper installation, and provides information on coatings and maintenance procedures to help preserve the new roof.

History of wood roofs ->

-- NPS Preservation Brief 19