Question? Just ask us!
Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
InspectAPedia ® Home
ROOFING INSPECTION & REPAIR
AMERICAN CEMWOOD ROOFING
BEST ROOFING PRACTICES
BUILT UP ROOFS
CATHEDRAL CEILING VENTILATION
CERTIFICATIONS for ROOFING CONTRACTORS
CHIMNEY FLASHING Mistakes & Leaks
COLD WEATHER ROOF TROUBLE
DECKS, ROOFTOP CONSTRUCTION
EPDM, RUBBER, PVC ROOFING
EXTRACTIVE BLEEDING on SHINGLES
FIRE RETARDANT PLYWOOD
FLASHING on BUILDINGS
FLAT ROOF MOISTURE & CONDENSATION
Green House or Solarium Roof Leaks
HEAT TAPES & CABLES on Roofs for Ice Dams
ICE DAM PREVENTION
MASONITE WOODRUF FIBERBOARD ROOFING
NOISE CONTROL for ROOFS
PLASTIC ROOFING TYPES
PVC, EPDM, RUBBER ROOFING
ROOF ARCHITECTURAL STYLES - PHOTO GUIDE
ROOF CLEANING RECOMMENDATIONS
ROOF COLOR RECOMMENDATIONS
ROOF INSPECTION SAFETY & LIMITS
ROOF LEAK DIAGNOSIS & REPAIR
ROOF NOISE TRANSMISSION
ROOF REPLACEMENT SNAFUs
ROOFING FELT UNDERLAYMENT REQUIREMENTS
ROOFING MATERIALS, Age, Types
SADDLE CONSTRUCTION at CHIMNEYS
SNOW GUARDS & SNOW BRAKES
STANDARDS for ROOFING
STRESS SKIN INSULATED PANELS
TEST LABS - ROOF SHINGLE
TREES & SHRUBS, TRIM OFF BUILDING
TRUSSES, Floor & Roof
UNDERLAYMENT REQUIREMENTS on ROOFS
VENTILATION in BUILDINGS
WALK-ON ROOF SURFACES
WARRANTIES for ROOF SHINGLES
WORKMANSHIP & ROOF DAMAGE
Wood shingle & wood shake roof installation specifications: this wood roof article describes the slope and exposure requirements for wood shake or wood shingle roofs, and provides detailed instructions on how and where to nail or fasten wood shingles/shakes on roofs.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved.
Our page top sketch is provided courtesy of Carson Dunlop Associates. Also see WOOD ROOF SHAKES INSTALLATION and WOOD ROOF SHEATHING, UNDERLAYMENT as well as our checklist of wood shingle installation specs at WOOD ROOF INSPECTION GUIDE. As discussed in BEST ROOFING PRACTICES,
Recommended exposures for shakes and shingles on roofs are shown in Tables 2-13 and 2-14.
Wood shingle head lap in a good installation exposes no more than 1/3 of the shingle to the weather. The head laps are 6", 7", or 9" respectively for 16", 18" or 24" long shingles respectively. More details are at WOOD ROOF INSPECTION GUIDE.
Wood Roof Shingle Exposure Specifications
Shingle exposures for wood roofs: the maximum weather exposure for wood shakes or wood shingles depends on the shingle size and the slope or pitch of the roof.
Allowable shingle exposure may also vary by the shingle grade - something that you might infer by visual inspection of the shingles, matching against wood shingle grade definitions, or if a shingle identification label can be located.
Exposure specifications for wood shakes are detailed at WOOD ROOF SHAKES INSTALLATION.
Carson Dunlop's sketch (left) illustrates the typical wood roof shingle application pattern.
The shingles are 4/10" to 1/2" in thickness, and wood shingles are installed with a 5" exposure (16" shingle length), 5 1/2" exposure (18" shingle length), or 7 1/2" exposure (24" wood shingle length).
The typical life of a wood shingle roof is 30-40 years, but life expectancy varies considerably depending on how the shingles were installed as well as on the pitch of the roof (its slope), and its sun and weather exposure. (Too much sun dries out the shingles leading to splitting, and too much shade may keep the shingles too damp, leading to rot.)
Shingle quality and shingle treatments (for example with preservatives or with protection against photoxidation) are important life factors as well. Wood shingles are installed on roofs with a slope of 6" in 12" for best performance but may be on a slope as low as 4/12.
Wood shingle nails need to be long enough to penetrate 1/2" (3/4" for the UBC) into the roof wood decking or nailing boards. The diamond-shaped nail tip itself has no holding power, just the roofing nail shank. So if you see shingle nails protruding through a plywood roof deck, that is not an error.
Nail specifications for wood shingles may vary by wood species; using western red cedar as an example, nails are to be corrosion resistant hot dipped galvanized, stainless steel, aluminum, or copper. In dry climates, good quality electrogalvanized staples, conforming to ASTM A641, are satisfactory according to the Cedar Shake and Shingle Bureau, but from our field experience we prefer nails.
Do not use blued steel or copper fasteners with cedar shakes or cedar shingles.
Wood shingle nailing pattern: in most applications only two nails are used per shingle, in order to permit movement without splitting as the shingle expands and contracts during changes in its moisture level. Keep nails about 3/4" to 1" (1" is for the U.B. Code), away from the side edges of the shingles and 1 1/2" (2" for UBC) above the butt line of the following course.
According to the Cedar Shake and Shingle Bureau, fasteners should be driven flush with the shake or shingle top surface, but no so deeply that the head crushes the wood.
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).
Eaves Flashing Details for Wood Shingle & Shake Roofs
Wood Shingle & Shake Nailing Guidelines
Continuing from from Best Practices Guide to Residential Construction:
Fastener Specifications for Wood Shingle & Shake Roofs: Nails, Staples
Wood Shingle Installation Specifications
Wood Shake Roof Installation Specifications: Felt Interlay or Felt Underlayment
Details for installing wood shake roofs are at WOOD ROOF SHAKES INSTALLATION.
Details about felt underlayment requirements and wood shingle or shake course interlayment are provided at WOOD ROOF SHEATHING, UNDERLAYMENT.
See "Fabricating and Installing Side-Lap Roof Shingles
in Eastern Pennsylvania", James Houston & John N. Fugelso.
In order to restore some of
Pennsylvania’s historic buildings,
the authors are recovering a lost
Frequently Asked Questions (FAQs) about how to install wood roof shingles or shakes
Questions & answers or comments about wood shingle and wood shake roofs: installation, inspection, troubleshooting, maintenance, & replacement.
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.