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Wood Shingle & Wood Shake Roof Wear Signs & Installation Problems InspectAPedia®  -     Signs of trouble on wood shingle or wood shake roofs Wood shingle roof inspection, failures, repair, product defects Roof inspection, leak detection, roof diagnosis, roof repair Key design details & references for wood shingle roofs

Here we discuss the inspection of wood shingle or wood shake roofing for indications of wear, poor installation, or other troubles that affect the remaining life of a wood shingle roof, wood shake roof, cedar shingle or cedar shake roof.

© Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use the links at page left to navigate this document or to go to Other Website Topics. Green links show where you are in our document & website.

Examples of Wood Roof Wear or Installation Problems that Limit Roof Life

Worn out wood shingle roofs: Our photo of a worn-out, curling, thin, split wood shingle roof is at above left. That's pretty easy to estimate.

Wood shingle placement & side lap offset: Take a close look at the new wood shingle roof at right. The side lap offset on this roof looks as if it barely complies with the 1.5" offset we want to see - it might be an improper installation, with many shingle butt joints offset by as little as 3/16" over one another. If so, this roof is likely to be leaky and it was not installed according to industry specifications. A closer look is needed.

At Anecdote of a "Bad" Roofing Contractor we give details about another case of improper nailing pattern for wood shingle roofs. In three successive courses of wood shingles or shakes, no butt joints should be in direct alignment (joints over joints), and between any two adjacent shingle courses the side lap offset of shingles over the course below should be 1 1/2" or more.

Wood shingle side gaps: Wood shingles are nailed with a 1/4" to 3/8" gap between adjacent shingles to accommodate shingle movement and dimensional change when shingles are wet by rain or melting snow. Omitting this gap can lead to a buckling, splitting, and failed wood shingle roof. Wood shakes require a still larger gap of 3/8" to 5/8" separation. More details are at Wood Roof Inspection Guide.

More Wood Shingle Roof Details & Indications of Wood Roof Trouble

Our photo of a moss-overgrown wood shingle roof is at above left. Additional examples of moss and lichens growth on roofs as well as discussion of how to remove and prevent this problem are at ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES.

Our photo of a curling and splitting wood shingle roof at above right demonstrates early wear and damage that might occur when wood shingles are installed over un-vented solid plywood decking.

Carson Dunlop's sketch at left shows an alternative method for providing (some) ventilation under cedar shingles when applied over a solid plywood roof deck. In our OPINION, installing wood shingles over un-vented solid plywood decking cuts the roof life in half, but this vent product might extend wood hingle life.

Carson Dunlop's sketch (below left) illustrates the traditional cedar shingle application pattern on spaced plank sheathing - a design that allows the shingles to dry quickly, extending the roof life. Our photo (below right) shows this traditional wood shingle roof installation at which the shingles were nailed on spaced sheathing, affording good ventilation.

For added details about proper wood shingle or wood shake roof installation, perhaps the most authoritative source of wood shingle and wood shake information is from the Western Red Cedar Shingle & Shake Bureau (now the Cedar and Shake Shingle Bureau, since not only western red cedar is used for roof shingles).

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ROOFING INSPECTION & REPAIR
ASBESTOS CEMENT ROOFING
ASPHALT ROOF SHINGLES
BUILT UP ROOFS
CERTIFICATIONS for ROOFING CONTRACTORS
CHIMNEY INSPECTION & REPAIRS
CHOOSING A ROOFING CONTRACTOR
CLAY TILE ROOFING
FIRE RETARDANT PLYWOOD
HEAT TAPES & CABLES on Roofs for Ice Dams
LOW SLOPE ROOFING MATERIALS
MASONITE WOODRUF FIBERBOARD ROOFING
MEMBRANE & SINGLE PLY ROOFS
METAL ROOFING TYPES
MODIFIED BITUMEN ROOFING
ROOF INSPECTION SAFETY & LIMITS
ROOF VENTILATION SPECIFICATIONS
ROOF VENTING ENERGY SAVING DETAILS
SLATE ROOF INSPECTION & REPAIR
SOD ROOFING
SIDING WOOD
STAIN DIAGNOSIS on Building Exteriors
STAIN DIAGNOSIS on Roofs
STANDARDS for ROOFING
STONE ROOFING
THATCH ROOFING
THERMAL EXPANSION of MATERIALS
THERMAL MASS in BUILDINGS
THERMAL MASS in UPSTAIRS
TILE ROOFING
WARRANTIES for ROOF SHINGLES
WOOD SHAKE & SHINGLE ROOFING
  Wood Roof Shingle Quality & Types
  Wood Shingle Specifications
  Wood Roof Wear or Installation Problems
  Wood Roof Inspection Guide
  Wood Roof Trouble Signs
  Wood Roof Inspection Guide
  Wood Shakes & Application Details
  Wood Roof Protective Coatings & Fire Rating
WORKMANSHIP & WIND DAMAGE

• Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
• "Choosing Roofing," Jefferson Kolle, January 1995, No. 92, Fine Homebuilding, Taunton Press, 63 S. Main St., PO Box 5506, Newton CT 06470 - 800-888-8286 - see http://www.taunton.com/FineHomebuilding/ for the magazine's website and for subscription information.
• The Cedar Shake and Shingle Bureau in the U.S.: Cedar Shake and Shingle Bureau, P.O. Box 1178
  Sumas, WA 98295-1178, or in Canada: Cedar Shake and Shingle Bureau, #2 - 7101 Horne Street
  Mission, BC V2V 7A2, 604-820-7700 E-mail: info@cedarbureau.com. The association can also be contacted by their website, cedarbureau.org where the association offers wood shingle installation instructions in the form of a manual - cedarbureau.org/installation/wall_manual/introduction.htm
• "Treatment of Cedar Shakes and Shingles," David Flickinger, RRO, Professional Roofing, October 1999, Rosemont IL.
  

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