About The Book
Finally, a book about slate roofing that is complete and up to date. This book is the most important tool for a slate roof project. Written for owners, architects, engineers, specifiers, installers and consultants, this book establishes a basis for communication and understanding for all parties. Addressed are issues such as estimating the cost of a slate roof, material handling, venting a slate roof, installing slate on cones and eyebrow dormers, the use of Ice and Water Shield, and many more topics neve r before written about in relation to slate roofing. Included is an entire section devoted to maintenance, repair and troubleshooting of existing slate roofs. 205 pages, 175+ figures, photos, tables and charts aid in clarifying important points of slate r oofing. Checklists and appendices will aid in organizing any slate roof project.

About the Author
The three authors work for Vermont Slate & Copper Services Inc., a snowguard manufacturer (they keep snow and ice from sliding off of roofs and injuring people or damaging property below). Vermont Slate & Copper Services Inc. used to be a slate roof insta llation company. It got our start when Brian was employed to remove slate from old structures in order to resell the slate. In the process, he saw how slate was installed in "the good old days." The next logical step was to begin a business to install sla te. Alan and John joined Brian as members of Vermont Slate Roofing. Even though the authors no longer roof, their roll as manufacturers keeps them in touch with the industry and gave them time to write a very much needed book. The authors are members of t he National Roofing Contractors Association (NRCA), North/East Roofing Contractors Association (NERCA), Roof Consultants Institute (RCI), Construction Specifiers Institute (CSI) and the National Trust for Historic Preservation.

Excerpted from The Slate Book :
How to Design, Specify, Install and Repair a Slate Roof
by Brian Stearns and Alan Stearns. Copyright 1998.
Used with permission.

Chapter 2 page 1 Building owners may choose slate for a variety of reasons, but foremost among them will be its feeling of elegance, its stateliness, and its long life cycle. Beyond the initial appeal and quality of a slate roof, there are many other fact ors that may influence design choices. From a design perspective, consider that slate is a natural stone with color that permeates naturally all the way through the stone. As such, it allows for a wide range of architectural effects. It is also easy to wo rk with. As a roofing material, it is non-combustible, fire-resistant, waterproof, practically non-absorbent, impervious to fungus and mold, wind-resistant (some manufacturers have obtained Dade County-approval), resistant to climatic change such as freez ing and thawing, and resistant to rot. For practical purposes, a slate roof has a long life cycle, requires minimum maintenance and no treatments, and is durable as well as dimensionally stable. In addition, slate is resistant to chemicals and is environm entally friendly. It does not curl and is easy to repair. Where to Start In the initial planning stages, you may want to look at some slate roofs on other houses or buildings and start collecting resources. It is helpful but not essential to find an archi tect who has experience with slate. Many architects have libraries or prior projects that can provide useful examples and pictures to aid in defining the desired appearance. Engineers and consultants can also provide a wide range of information that you m ay wish to take advantage of, especially if you are considering reroofing an existing structure. Speaking to slate quarry personnel and qualified roofers can also provide a wealth of information. One of the first steps in designing a slate roof is to dete rmine the basic kind of roof needed for the structure. You may want to review the Roof Parts Nomenclature in Appendix G to familiarize yourself with the terminology used to describe different roof styles and features. The figures show some standard kinds of roofs and design options.

Slate Roof Designs
The next step is to make some preliminary decisions about the design of the slate roof itself. Historically, slate roofs have been categorized into three classifications Standard, Textural, and Graduated which refer to the type and thic kness of the slate itself. Since these classifications were developed at a time when everyone involved in construction had a general knowledge of slate roofing, they were understood as generalizations. Over time, specific names and descriptions have been applied to these classifications in an attempt to define or describe them more clearly. As general slate roofing knowledge has faded, some of these added descriptors have caused some confusion. Today, the classifications have remained essentially the same , but the definitions have evolved. Table 2-1 on the next page contains an expanded list of slate roof types and variables within those types. An explanation of each type and variable follows. Chapter 6 page 1 The installation of slate should not begin un til the entire roof has been laid out to the greatest degree possible. On surfaces which are not accessible without roof scaffolding, only the very bottom and the very top of the roof can be laid out initially. Successive layout will progress as roof scaf folding is installed. This is a critical step in slate roofing because of the nature of the material and how it is installed. Slate shingles are not as flexible or adjustable as other materials, such as composition shingles. This chapter explains the step s for completing the roof layout. Before you begin, assume that the roof structure is not perfectly square and that the valleys and hips are not perfectly straight. This is by no means intended to be a criticism of the carpenters and framers who built the building. In many cases, slate is installed on existing buildings that need to be reroofed. Most existing buildings will have moved and settled somewhat over the years, creating a situation where the roof lines are no longer perfect. As a rule, it is saf est to assume that no building, new or existing, is perfectly square. The roof layout involves snapping horizontal chalk lines to align the top of each course of slate shingles. Vertical lines are not always required. All lines to be followed at a later d ate should be laid out using a chalk that will not wash away. Red, yellow, and some orange chalks are said to be permanent, but check the label on the side of the bottle before starting. Blue chalk is not a permanent color and should generally not be used for the roof layout; however, since it will wash away, it may be appropriate when snapping lines on the surface of the slate itself. Slate roof shingles vary in length, so there will almost always be slight variations in the alignment of the slate butts. These variations are usually minimal, they are rarely seen when looking at the roof from the ground, and the uneven texture of the slate surface usually hides whatever variations may occur. However, some inexperienced project management people may panic when they observe this variation from the roof level. Chapter 8 page 1 After putting considerable effort into planning, ordering, roof layout, and preparation, you are at last ready to begin installing the slate. This chapter explains the procedures and techniques for working on a slate roof, cutting and punching the slate, and installing it.

Working on a Slate Roof
Slate is considered a steep slope roof application. For several reasons, the use of roof scaffolding is essential when working on a slate roof. First, unlike some roofing shingles, slate does not stack well on a sloped surface. Bec ause it is smooth and flat, it will slide off a sloped roof. Second, as much as possible, the installer wants to avoid walking over the finished roof. Third, proper scaffolding provides safe access to the roof surface. Whenever using scaffolding, consult OSHA rules and regulations. With composition shingles, cedar shakes and shingles, and with most tiles, the roof is prepared as specified, coursing is laid out, and flashing details that can be installed are. The roof shingles are then distributed in small amounts over the entire roof. As the installer works, he simply grabs shingles from the nearest pile and installs them. These roofs are often installed with the roofers working from above and/or beside the shingles. Because the shingles can be stacked al l over the roof without sliding off, this material loading approach makes perfect sense. Slate, however, needs to be stacked on a platform of some kind to keep it from sliding. Unlike some roofing materials, such as tile and standing seam metal that can b e installed vertically, slate must be installed horizontally. The roof must be scaffolded as the installers proceed up slope. Standard slate roof brackets can be used to install the scaffold. Once the brackets are properly installed, a plank is laid from bracket to bracket to create a bridge or roof scaffold. The slate can then be stacked flat on the planks and used as needed.