A. General:
1. Roof Slope:
a. Shingle and tile roof, five (5) in twelve (12) minimum.
b. Shingle roof less than five (5) in twelve (12) but not less than two (2) in twelve (12) shall be applied in strict accordance with manufacturer's specifications cementing or otherwise protecting tabs against wind uplift.
c. Built-up roofs (gravel or slag surface), two (2) in twelve (12) maximum.
d. Built-up roofs with mineral surface cap sheet, three (3) in twelve (12) maximum.
e. When materials and method of application provide precautions in excess of these four (4) minimum requirements to assure a weather-tight roof, above roof slopes may be reduced subject to acceptance by Building Official. Application and materials as outlined by "Manufacturers Selection and Application of Asphalt Roofing and Siding Products" published by A.R.I.B. shall be considered as acceptable good practice.
2. Double starting row, on all shingle applications.
3. Nails for attaching roof covering, copper or hot-dipped galvanized nails. Staples not permitted.
B. Asphalt Shingles:
1. Fire Underwriters' Class C label on each bundle.
2. Approximate Shipping Weights Per Square:
a. Square butt strip, two hundred ten (210) pounds.
b. Hexagonal strip, one hundred sixty five (165) pounds.
c. Individual shingles, two hundred fifty (250) pounds.
3. Exposure as required for Fire Underwriters' Class C label.
4. Headlap as recommended by manufacturers; minimum two inches (2").
5. Double thickness at all points. Cut-outs and vertical spacing three-fourths inch (3/4") or less may be disregarded.
6. Underlay: Asphalt-saturated felt; weight approximately fifteen (15) pounds per one hundred (100).
C. Wood Shingles:
1. Edge-grain, tapered shingles (No. 1 grade).
2. Minimum Size:
Length (inches)
|
Thickness
|
16 | 5 Butts in 2 inches |
18 | 5 Butts in 21/4 inches |
24 | 4 Butts in 2 inches |
3. Maximum Exposure:
Slope of Roof | Exposure for shingle length - inches | |||
Rise
|
Run
|
16
|
18
|
24
|
3 to 7 | 12 | 4 | 41/2 | 6 |
7 to 18 | 12 | 5 | 51/2 | 71/2 |
4. Underlay not permitted.
D. Asbestos Cement Shingles:
1. Quality: Dense, hard structure and thoroughly seasoned. See FS-SS-S-291c.
2. Fire Underwriters' Class A or B label on each bundle.
3. Underlay: One layer asphalt-saturated felt, approximately thirty (30) pounds per one hundred (100) square feet.
4. American Method:
a. Standard shingle: Minimum weight per square, four hundred seventy (470) pounds.
Length of Shingle Inches
| Maximum Exposure
Inches
|
16 | 7 |
15 | 61/2 |
12 | 5 |
b. Strip shingle: Minimum weight per square, two hundred eighty five (285) pounds.
5. Dutch Method:
a. Minimum weight per square, two hundred sixty five (265) pounds.
b. Minimum headlap, three inches (3").
c. Minimum sidelap, four inches (4").
6. French or Hexagonal Method:
a. Minimum weight per square, two hundred fifty (250) pounds.
b. Minimum overlap two (2) edges, three inches (3").
E. Tile Roofing:
1. Quality: Hard-burned roofing tile.
2. Underlay: One layer asphalt saturated felt approximately thirty (30) pounds per one hundred (100) square feet.
3. Shingle Tile, American Method:
Length of Shingle Inches
| Maximum Exposure
Inches
|
16 | 7 |
15 | 61/2 |
14 | 6 |
12 | 5 |
4. Interlocking Tile and Curved Tile: Lay in accordance with manufacturer's recommendations.
F. Slate Shingles:
1. Quality: Free from knots or knurls and of reasonably smooth cleavage. See FS-SS-S-451.
2. Underlay: Asphalt-saturated felt approximately thirty (30) pounds per one hundred (100) square feet.
3. Laid American Method:
a. Minimum thickness, three-sixteenths inch (3/16").
b. | Length of Shingle Inches | Maximum Exposure Inches |
18 | 71/2 | |
16 | 61/2 | |
14 | 51/2 | |
12 | 41/2 | |
10 | 31/2 |
G. Built-Up Roofs:
1. Asphalt or Tar and Gravel Coverings, Including Flashings: Comply with requirements of Underwriters' Laboratories, Inc.; built-up roof coverings, minimum three (3) ply.
2. Apply according to manufacturer's directions.
3. Each Ply of Felt: Minimum weight, fifteen (15) pounds per one hundred (100) square feet.
4. Surface Weight:
a. Roofing gravel or crushed stone, approximately four hundred (400) pounds per one hundred (100) square feet; or
b. Crushed slag, approximately three hundred (300) pounds per one hundred (100) square feet.
c. Other material approved as to quality and weight by Building Official.
5. Top ply of felt and crushed stone or slag surfacing may be replaced with one layer of mineral surfaced cap sheet, minimum weight eighty five (85) pounds per square.
H. Metal Roofs:
1. Materials:
a. Galvanized sheet metal: Twenty six (26) gauge sheets, one and twenty five one-hundredths (1.25) ounces (total weight both sides) zinc coating per square foot.
b. Copper: Sixteen (16) ounce soft (roofing temper).
c. Roofing tin: Forty (40) pound coating.
d. Lead: Sheet lead, two and one-half (21/2) pounds per square foot.
2. Nails:
a. Hard copper or copper alloy, for copper roofs.
b. Hot-dipped galvanized, for galvanized, sheet metal roofs.
3. Seams: Flat or standing; flat seams, locked and soldered.
4. Provide for expansion.
I. Other Types of Roof Coverings: Roof coverings such as metal shingles, canvas or roll roofing may be used when the type and weight of material and method of application are acceptable to the Building Official. (Ord. 0-71-12, 3-11-71)