Application - Roofing
 
Western Red Cedar Shingles
 
Shingle Application
 
Regardless of style, the following basic application details (Figure 4) must be observed.
  1. Shingles must be doubled or tripled at all eaves.

  2. Butts of the first course shingles should project 1 1/2" beyond the fascia.
 
 
  1. Spacing between adjacant shingles (joints) should be a minimum of 1/4" (6.35 mm) and a maximum of 3/8" (9.525 mm).

  2. Joints in any one course should be separated not less than 1 1/2" (38.1mm) from joints in adjacent courses; and in any three courses, no two joints should be in direct alignment.
 
 

ROOF FASTENER GUIDELINES
 
Nails
 
Each shingle or shake should be applied with two corrosion-resistant fasteners, such as stainless steel (Type 304 or 316), hot-dipped zinc coated, or aluminum nails. If preservative treated shingles or shakes are installed the treating company's recommendations regarding the compatibility of the preservative chemicals with the fastener should be followed. Minimum nail lengths are shown in Table 1.
 
 
 
Staples should be aluminum or stainless steel (type 304 or 316) 16 gauge. Two staples should be driven per shingle or shake with the staple crowns (7/16", 11.113 mm) (miniumn) horizontal to the shingle or shake butt and driven in the same location as nails relative to the sides and overlapping butt line. Staples should be long enough to penetrate the sheathing at least 1/2" (12.7 mm) and driven flush with the surface of the shingle or shake.
 

SPECIFICATION GUIDELINES
 
This information has been designed to aid architects and builders in specifying red cedar shingles and handsplit shakes. It suggests a standardized terminology and style for ordering in the hope of improving accuracy and it incorporates a general outline of the latest application information. Please note, however, that this is a specification guide only. It is not intended to be a complete reference to the characteristics or application of red cedar shingles and shakes. Comprehensive information on such subjects is available from your local building code department.
General Specification Data
  1. The contractor shall cover all roof surfaces with shingles or shakes bearing the I.C.B.O. or other official grade marked label.

  2. Shingles/shakes for roofs shall be (specify grade and length).

  3. Shingles/shakes for outer courses shall be (specify grade and length).

  4. Shingles/shakes for undercourses shall be (specify grade and length).

  5. Shingles/shakes shall be laid with a weather exposure of (specify in inches/millimeters).
Roof Application-Sheathing Boards
  1. Shingles and shakes shall be applied over spaced sheathing. Solid sheathing is acceptable and may be required in seismic regions or under treated shakes and shingles. In areas where wind-driven snow is common, solid sheathing is recommended under shakes.

  2. All open sheathing shall be 1" x 4" (25.4 mm x 101.6 mm) or 1"x 6" (25.4 mm x 152.4 mm) boards. (1"x 6" (25.4 mm x 152.4 mm) boards for shakes).

  3. All solid sheathing shall be lumber, such as shiplap, or softwood panels, applied according to specifications of the American Plywood Association.
Roof Felt Interlay (for shakes only)
  1. Contractor shall apply a 36"(914.4 mm) wide strip of No. 15 minimum roofing felt at the eave line. An 18" (457.2 mm) wide strip of No. 30 roofing felt (or No. 15 felt depending upon code requirements) shall be applied over the top portion of the shakes and extend onto the sheathing. Bottom edge of felt shall be positioned at a distance above the butt equal to twice the weather exposure. Note: felt interlay between courses is not necessary when straight-split, or tapersplit shakes are applied in snow-free areas at weather exposures of less than one-third the total shake length (3-ply roof).

  2. Shingles/shakes shall be at least double at all eaves.

  3. Butts of the shingles/shakes in the first course on roofs shall project 1/2" (38.1 mm) from the edge of roof eaves to insure proper spill into gutters.

  4. Shingles shall be spaced apart not less than 1/4" (6.35 mm), nor more than 3/8" (9.525 mm), 13. Shakes shall be spaced apart not less then 3/8", nor more than 5/8" (15.875 mm).

  5. Shakes shall be spaced apart not less than 3/8" (9.525 mm), nor more than 5/8" (15.875 mm).

  6. No. 1 shingles/shakes shall be applied with weather exposures consistent with the following table (Table 6):
 
 
  1. Chimney flashing shall extend up the chimney to a height not less than 6 inches, and up the roof slope to a point equal in height to the flashing on the chimney but never less than 1 1/2 times the shingle/shake exposure. (All metal flashings should be painted).

  2. Apron counter flashing shall extend to within 1" (25.4 mm) of the surface of the finished roof.

  3. Where saddles or crickets are formed in back of chimneys, curves or similar vertical surfaces, they shall be carried not less than 10" (254 mm) under the shingles/shakes.

  4. Step flashing shall be used where vertical surfaces occur in connection with slopes. They shall be formed of separate pieces. Flashing shall extend horizontally not less than 3" (76.2 mm) and up the vertical wall so that they shall be lapped by the counter flashing not less than 4" (101.6 mm). Shall be installed step fashion and each piece shall lap not less than 3" (76.2 mm). If other than masonry is used the flashing shall extend up the wall not less than 3" (76.2 mm) behind the sheathing paper.

  5. Dormer flashings shall run 3" (76.2 mm) up under the sheathing paper and not less than 3" (76.2mm) horizontally.

  6. Window caps and all other projections at points where rain water accumulates must be provided with flashings, such flashings must extend a distance of at least 3" (76.2 mm) up the wall behind the sheathing paper.

  7. All pipes projecting through roofs shall be flashed and counter flashed. These flashings shall extend 3" (76.2 mm) up under the sheathing paper and not less than 3" (76.2 mm) horizontally. They shall be of sufficient length to cover the shingle/shake course next below the pipe, and to extend up under the straight course above as far as possible without punctured by nails. (Where plumbing vents are carried through roof surfaces, they are generally flashed by the plumber with lead. The lead is carried up on the outside of the pipe and cut off flush with the top of the pipe, and counter flashed with lead extending 4" (101.6 mm) down the outside of the pipe and 2" (50.8 mm) down the inside of the pipe).
Hips and Ridges
  1. All shingles/shakes hips and ridges shall be of alternate overlap type applied at the same exposure as filed of roof and with nails long enough to penetrate into sheathing at least 1/2" (12.7 mm) ( 3/4 " (19.05 mm) per Uniform Building Code, (UBC).
Valleys
  1. Shingles/shakes extend into the valley shall be sawed to the proper miter.

  2. Do not break joints into valley.

  3. Do not lay shingles or shakes with grain parallel with the centerline of valleys.

  4. All valleys shall be installed with shingles/shakes lapping the valley flashing not less than 7" (177.8 mm) on each side.

  5. On shingle roofs of less than 1/2 pitch, flashing should extend at least 10" (254 mm) on each side.

  6. For shakes, metal valley sheets shall be center-crimped; of 20 " (508 mm) minimum width; underlaid with a strip of No. 15 minimum roofing felt over the sheathing, and coated with a metal paint. When spaced sheathing is used, the felt may be omitted under metal valley sheets.

  7. Valley metals that have proved reliable in a particular geographic region should be selected.
Nails and Nailing Shingles/Shakes
  1. Nails shall be driven flush but not so that the nail head crushes the wood. They shall be placed approximately 3/4" (19.05 mm) to 1" (25.4 mm) from the side edges of the shingles/shakes and 1 1/2" (38 .1 mm) to 2" (50.8 mm) above the butt line of the following course.

  2. Each roof shingle/shake shall be secured with two-driven, corrosion-resistant nails. (Specify size).

  3. Use 3d "box" nails for new roof with 16" (406.4 mm) and 18" (457.2 mm) shingles.

  4. Use 4d "box" nails for new roofs with 24" (609.6 mm) shingles.

  5. Use 4d "box" nails for over-roofing with 16" (406.4 mm) and 18" (457.2 mm) shingles, and for hips and ridges.

  6. Roof shakes shall be secured with corrosion resistant, hot-dipped, zinc-coated nails or aluminum or stainless steel nails -type 304 or 316. Nails shall be long enough to penetrate sheathing at least 1/2" (12.7 mm) (3/4" (19.05 mm) per UBC). 6d nails are usually adequate, but longer nails shall be used as shake thickness or weather exposure dictates.

  7. If staples are used they shall be stainless (type 304 or 316) or aluminum. In drier climate regions, having a climate index or less than 35 as indicated by the USDA Forest Service, good quality electro-galvanized staples, conforming to ASTM A641, have proven satisfactory for applying untreaded shakes or shingles. Blue steel fasteners should not be used.

 

Home | Shakes | Shingles | Hip and Ridge | About Us | Contact Us | Sign In

© Copyright 2008 . All rights reserved.