InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
This article discusses flashing installation details for wood shingle or wood shake roofs. This article series discusses best practices in the selection and installation of residential roofing. This article includes excerpts or adaptations from Best Practices Guide to Residential Construction, by Steven Bliss, courtesy of Wiley & Sons.
Our page top photo shows a wood shingle roof on the historic Mesier Homestead in Wappingers Falls, NY.
Also see the roofing article links listed at the "More Reading" links at the bottom of this article and our roofing home page: ROOFING INSPECTION & REPAIR.
Roof flashings should be at least 26-gauge, corrosion resistant
sheet metal, preferably painted galvanized steel
or painted aluminum.
Copper Flashing and Cedar Roofing?
Copper is a popular flashing material
with wood roofs, although some experts caution
against using copper in direct contact with red cedar or its
runoff, since the soluble tannins in cedar can etch copper
and, in extreme cases, lead to perforation of the flashing
within 10 to 20 years (see also “FLASHING WALL DETAILS - Copper,” and “Metal Choices for Metal Roof Systems - Copper”).
Premature wood shingle roof failures have been documented in areas of the
eastern United States that are subject to acid rain, leading
the Cedar Shake and Shingle Bureau to advise against
using copper flashing in areas east of the Great Lakes that
are exposed to acid rain.
Another approach endorsed by
the Copper Development Association is to design flashing
joints with a cant or hem that holds the edge of the cedar
shingle slightly away from the flashing. The gap prevents
water from being wicked into the joint, bathing the copper
in the acidic solution.
Valley Specifications for Wood Shingle/Shake Roofs
Wood roofs typically use open valley designs.
While the International Residential Code (IRC) only requires
the valley flashing to extend a minimum of 10 inches
up each side of the valley for shingles and 11 inches for
shakes, most contractors install 24- to 36-inch-wide valley
flashing based on the area and pitch of the roof planes being
The valley metal should be protected by an extra
layer of 36-inch-wide No. 30 felt installed directly under
the metal or a layer of self-adhesive bituminous membrane
applied directly to the sheathing.
It is best to set aside the
widest shingles or shakes for use in the valley to keep nails
at least 12 inches from the valley centerline (Figure 2-52) shown above.
Chimneys and Skylight Flashing Specifications for Wood Shingle/Shake Roofs
Chimneys on wood shingle or shake roofs are flashed conventionally,
using step flashing on the sides in accordance
with Table 2-16 below.
Use a soldered apron flashing below the
chimney and a soldered head flashing at the top. Larger
chimneys with significant water flow behind them should
have a chimney cricket above.
Air Vent/A Gibraltar Company
A complete line of roof ventilation products, including
shingle-over and exposed-ridge vents with exterior wind
baffles and internal weather filters. Also soffit and drip
edge vents and passive and powered attic turbine-type
Shingle-over ridge vents. Low-profile Roll Vent uses nylonmatrix.
Extractor vent is molded polypropylene with internal
and external baffles.
Shingle-over low-profile ridge vents, including Cor-a-vent,
Fold-a-vent, and X-5 ridge vent, designed for extreme
weather. Corrugated core.
GAF Materials Corp.
Cobra vent: roll-out shingle-over ridge vent with a
102 CHAPTER 2 | Roofing
Mid-America Building Products
Ridge Master and Hip Master shingle-over molded plastic
ridge vents with internal baffles and foam filter
VentSure corrugated polypropylene ridge vents; also
passive roof vents and soffit vents
Trimline Building Products
Shingle-over low-profile ridge vents, Flow-Thru battens for
Elk Premium Building Products
Highpoint polypropylene shingle-over ridge vents
Tamko Roofing Products
Shingle-over ridge matrix–type Roll Vent and Rapid Ridge
(nail gun version) and Coolridge, which is molded
polypropylene with external and internal baffles
Venting Wood Roof Underlayments
Cedar Breather, a
3/8 -in.-thick matrix-type underlayment
designed to provide ventilation and drainage space under
More Information about Roofing Materials, Methods, Standards
Asphalt Roofing Manufacturers Association (ARMA)
Cedar Shake and Shingle Bureau
No FAQs have been posted for this page. Try the search box below or CONTACT US by email if you cannot find the answer you need at InspectApedia.
Ask a Question or Search InspectApedia
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.
Green Roof Plants: A Resource and Planting Guide, Edmund C. Snodgrass, Lucie L. Snodgrass, Timber Press, Incorporated, 2006, ISBN-10: 0881927872, ISBN-13: 978-0881927870. The text covers moisture needs, heat tolerance, hardiness, bloom color, foliage characteristics, and height of 350 species and cultivars.
Green Roof Construction and Maintenance, Kelley Luckett, McGraw-Hill Professional, 2009, ISBN-10: 007160880X, ISBN-13: 978-0071608800, quoting: Key questions to ask at each stage of the green building process Tested tips and techniques for successful structural design
Construction methods for new and existing buildings
Information on insulation, drainage, detailing, irrigation, and plant selection
Details on optimal soil formulation
Illustrations featuring various stages of construction
Best practices for green roof maintenance
A survey of environmental benefits, including evapo-transpiration, storm-water management, habitat restoration, and improvement of air quality
Tips on the LEED design and certification process
Considerations for assessing return on investment
Color photographs of successfully installed green roofs
Useful checklists, tables, and charts
Roofing The Right Way, Steven Bolt, McGraw-Hill Professional; 3rd Ed (1996), ISBN-10: 0070066507, ISBN-13: 978-0070066502
Slate Roofs, National Slate Association, 1926, reprinted 1977
by Vermont Structural Slate Co., Inc., Fair Haven, VT 05743, 802-265-4933/34. (We recommend this book if you can find it. It
has gone in and out of print on occasion.)
Roof Tiling & Slating, a Practical Guide, Kevin Taylor, Crowood Press (2008), ISBN 978-1847970237, If you have never fixed a roof tile or slate before but have wondered how to go about repairing or replacing them, then this is the book for you. Many of the technical books about roof tiling and slating are rather vague and conveniently ignore some of the trickier problems and how they can be resolved. In Roof Tiling and Slating, the author rejects this cautious approach. Kevin Taylor uses both his extensive knowledge of the trade and his ability to explain the subject in easily understandable terms, to demonstrate how to carry out the work safely to a high standard, using tried and tested methods.
This clay roof tile guide considers the various types of tiles, slates, and roofing materials on the market as well as their uses, how to estimate the required quantities, and where to buy them. It also discusses how to check and assess a roof and how to identify and rectify problems; describes how to efficiently "set out" roofs from small, simple jobs to larger and more complicated projects, thus making the work quicker, simpler, and neater; examines the correct and the incorrect ways of installing background materials such as underlay, battens, and valley liners; explains how to install interlocking tiles, plain tiles, and artificial and natural slates; covers both modern and traditional methods and skills, including cutting materials by hand without the assistance of power tools; and provides invaluable guidance on repairs and maintenance issues, and highlights common mistakes and how they can be avoided.
The author, Kevin Taylor, works for the National Federation of Roofing Contractors as a technical manager presenting technical advice and providing education and training for young roofers.
The Slate Roof Bible, Joseph Jenkins, www.jenkinsslate.com,
143 Forest Lane, PO Box 607, Grove City, PA 16127 - 866-641-7141 (We recommend this book).