HomeMy WebLinkAbout04012004 BSC Agenda Item 7 •
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BSC
April ist, 2004
Roofing Materials
Agenda Item # 7
§RR902
ROOF CLASSIFICATION
I
§RR902.1 Roofing covering materials. Roofs shall be covered with
materials as set forth in §RR904 and §RR905. Class A, B or C
roofing shall be installed in areas designated by law as requiring their
use or when the edge of the roof is less than 3 feet (914 mm) from a
property line. Classes A, B and C roofing required to be listed by this
section shall be tested in accordance with UL 790 or ASTM E 108. Roof
assemblies with coverings of brick, masonry, slate, clay or concrete roof
tile, exposed concrete roof deck, ferrous or copper shingles or sheets,
and metal sheets and shingles, shall be considered Class A roof coverings.
§RR902.2 Wood shingles and shakes. When testing wood shingles and shakes
in accordance with ASTM E 108 (including the rain test) and ASTM D 2898,
the fire tests shall include the intermittent flame test, spread of flame
test, burning brand test and flying brand test; additionally, at the
conclusion of the rain test, test panels shall be subjected to the
intermittent flame test, burning brand test and flying brand test.
§RR902.2.1 Fire-retardant-treated shingles and shakes. Fire-retardant-
treated wood shakes and shingles shall be treated by impregnation with
chemicals by the full-cellvacuum-pressure process, in accordance with
AWPA Cl. Each bundle shall be marked to identify the manufactured unit
and the manufacturer, and shall also be labeled to identify the
classification of the material in accordance with the testing required
in §RR902.2, the treating company and the quality control agency.
§RR904
. MATERIALS •
§RR904.1 Scope. The requirements set forth in this section shall apply
to the application of roof covering materials specified herein. Roof
assemblies shall be applied in accordance with this chapter and the
manufacturer's installation instructions. Installation of roof assemblies
shall comply with the applicable provisions of §RR905.
§RR904.2 Compatibility of materials. Roof assemblies shall be of
materials that are compatible with each other and with the building or
structure to which the materials are applied.
§RR904.3 Material specifications and physical characteristics. Roof
covering materials shall conform to the applicable standards listed in
this chapter. In the absence of applicable standards or where materials
are of questionable suitability, testing by an approved testing agency
shall be required by the building offical to determine the character,
quality and limitations of application of the materials.
§RR904.4 Product identification. Roof covering materials shall be
delivered in packages bearing the manufacturer's identifying marks and
approved testing agency labels when required. Bulk shipments of
materials shall be accompanied with the same information issued in the
form of a certificate or on a bill of lading by the manufacturer.
§RR905
REQUIREMENTS FOR ROOF COVER
§RR905.1 Roof covering application. Roof coverings shall be applied in
accordance with the applicable provisions of this section and the
manufacturer's installation instructions .
§RR905.2 Asphalt shingles. The installation of asphalt shingles shall
comply with the provisions of this section.
§RR905.2.1 Sheathing requirements. Asphalt shingles shall be fastened
to solidly sheathed decks.
§RR905.2.2 Slope. Asphalt shingles shall only be used on roof slopes of
two units vertical in 12 units horizontal (2:12) or greater. For roof
slopes from two units vertical in 12 units horizontal (2 :12) up to four
units vertical in 12 units horizontal (4:12) , double underlayment
application is required in accordance with §RR905.2.7.
§RR905.2.3 Underlayment. Unless otherwise noted, required underlayment
shall conform with ASTM D 226, Type I, or ASTM D 4869, Type I.
Self-adhering polymer modified bitumen sheet shall comply with ASTM D
1970.
§RR905.2.4 Asphalt shingles. Asphalt shingles shall have self-seal
strips or be interlocking, and comply with ASTMD 225 or D 3462.
§RR905.2.5 Fasteners. Fasteners for asphalt shingles shall be
galvanized steel, stainless steel, aluminum or copper roofing nails,
minimum 12 gage [0.105 inch (2.67 mm) ] shank with a minimum 3/8-inch
(9.5 mm) diameter head, ASTM F 1667, of a length to penetrate through
the roofing materials and a minimum of 3/4 inch (19.1 mm) into the roof
sheathing. Where the roof sheathing is less than 3/4 inch (19.1 mm)
thick, the fasteners shall penetrate through the sheathing. Fasteners
shall comply with ASTM F 1667.
§RR905.2.6 Attachment. Asphalt shingles shall have the minimum number
of fasteners required by the manufacturer. For normal application,
asphalt shingles shall be secured to the roof with not less than four
fasteners per strip shingle or two fasteners per individual shingle.
Where the roof slope exceeds 20 units vertical in 12 units horizontal
(20:12) , special methods of fastening are required.
EXCEPTION: Asphalt strip shingles shall have a minimum of six
fasteners per shingle where the roof is in one of the following
categories:
1. The basic wind speed per Figure RR301.2 (4) is 110 miles per
hour (177 km/h) or greater and the eave is 20 feet (6096 mm) or
higher above grade.
2. The basic wind speed per Figure RR301.2 (4) is 120 miles per hour
(193 km/h) or greater.
3 . Special wind zones per Figure RR301.2 (4) .
§RR905.2.7 Underlayment application. For roof slopes from two units
vertical in 12 units horizontal (17-percent slope) , up to four units
vertical in 12 units horizontal (33-percent slope) , underlayment shall
be two layers applied in the following manner. Apply a 19-inch (483
mm) strip of underlayment felt parallel with and starting at the
eaves, fastened sufficiently to hold in place. Starting at the eave,
apply 36-inch-wide (914 mm) sheets of underlayment, overlapping
successive sheets 19 inches (483 mm) , and fastened sufficiently to
hold in place. For roof slopes of four units vertical in 12 units
horizontal (33-percent slope) or greater, underlayment shall be one
layer applied in the following manner. Underlayment shall be applied
shingle fashion, parallel to and starting from the eave and lapped 2
inches (51 fastened sufficiently to place. End laps
shall be off by 6 feet (1829 mm) .
§RR905.2.7.1 Ice protection. In areas where the average daily
temperature in January is 25IF (-4IC) or less, an ice barrier that
consists of a least two layers of underlayment cemented together or
of a self-adhering polymer modified bitumen sheet, shall be used in
lieu of normal underlayment and extend from the eave' s edge to a
point at least 24 inches (610 mm) inside the exterior wall line of
the building.
§RR905.2.7.2 Underlayment and high wind. Underlayment applied in
areas subject to high winds [greater than 110 mph (177km/h) per
Figure RR301.2 (4) ] shall be applied with corrosion-resistant
fasteners in accordance with manufacturer's installation instructions.
Fasteners are to be applied along the overlap not farther apart than
36 inches (914 mm) on center.
§RR905.2.8 Flashing. Flashing for asphalt shingles shall comply with
this section.
§RR905.2.8.1 Base and cap flashing. Base and cap flashing shall be
installed in accordance with manufacturer's installation
instructions. Base flashing shall be ofeither corrosion-resistant
metal of minimum nominal 0.019-inch (0.483 mm) thickness or mineral
surface roll roofing weighing a minimum of 77 pounds per 100 square
feet (3.76 kg/m^2) . Cap flashing shall be corrosion-resistant metal
of minimum nominal 0.019-inch (0.483 mm) thickness.
§RR905.2.8.2 Valleys. Valley linings shall be installed in
accordance with manufacturer's installation instructions before
applying shingles. Valley linings of the following types shall be
permitted:
1. For open valley (valley lining exposed) lined with metal, the
valley lining shall be at least 24 inches (610 mm) wide and of any
of the corrosion-resistant metals in Table RR905.2 .8.2 .
2 . For open valleys, valley lining of two plies of mineral surface
roll -roofing, complying with ASTM D 249,_ shall he permitted. The
bottom layer shall be 18 inches (457 mm) and the top layer a
minimum of 36 inches (914 mm) wide.
3 . For closed valleys (valley covered with shingles) , valley
lining of one ply of smooth roll roofing complying with ASTM D 224
Type II or Type III and at least 36 inches (914 mm) wide or valley
lining as described in Items 1 and 2 above shall be permitted.
Specialty underlayment complying with ASTMD 1970 may be used in
lieu of the lining material.
TABLE RR905.2.8.2
VALLEY LINING MATERIAL
MINIMUM
THICKNESS I I WEIGHT
MATERIAL I (inches) I GAGE I (pounds)
Copper -- -- 1
Aluminum 0.024 -- --
Stainless steel -- 28 --
Galvanized 26 (zinc
steel 0.0179 coated G90) --
Zinc alloy 0.027 --
Lead -- -- 2-1/2
Painted 1106 -- -- I 20
For SI: 1 inch = 25 .4 mm,
1 pound = 0 .454 kg.
§RR905.2.8.3 Crickets and saddles. A cricket or saddle shall be
installed on the ridge side of any chimney greater than 30 inches
(762 mm) wide. Cricket or saddle coverings shall be sheet metal or
of the same material as the roof covering.
§RR905.2.8.4 Sidewall flashing. Flashing against a vertical sidewall
shall be by the step-flashing method.
§RR905.2.8.5 Other flashing. Flashing against a vertical front wall,
as well as soil stack, vent pipe and chimney flashing, shall be
applied according to asphalt shingle manufacturer's printed
instructions.
§RR905.3 Clay and concrete tile. The installation of clay and concrete
shall comply with the provisions of this section. Clay roof tile shall
comply with ASTM C1167.
§RR905.3.1 Deck requirements. Concrete and clay tile shall be
installed only over solid sheathing or spaced structural sheathing
boards.
§RR905.3.2 Deck slope. Clay and concrete roof tile shall be installed
on roof slopes of two and one-half units vertical in 12 units
horizontal (2-1/2:12) or greater. For roof slopes from two and one-
half units vertical in 12 units horizontal (2-1/2:12) to four units
vertical in 12 units horizontal (4:12) , double underlayment application
is required in accordance with §RR905.3.3.
§RR905.3.3 Underlayment. Unless otherwise noted, required underlayment
shall conform with ASTM D 226, Type II; ASTM D 2626, Type I; or ASTM D
249 mineral surfaced roll roofing.
0RR905.3.3.1 Low slope roofs. For roof slopes from two and one half -•
units vertical in 12 units horizontal (2-1/2:12) , up to four units
vertical in 12 units horizontal (4:12) , underlayment shall be a
minimum of two layers underlayment applies as follows:
1. Starting at the eave, a 19-inch (483 mm) strip of underlayment
shall be applied parallel with the eave and fastened sufficiently
in place.
2 . Starting at the eave, 36-inch-wide (914 mm) strips of
underlayment felt shall be applied, overlapping successive sheets
19 inches (483 mm) , and fastened sufficiently in place.
§RR905.3.3.2 High slope roofs. For roof slopes of four units
vertical in 12 units horizontal (4:12) or greater, underlayment shall
be a minimum of one layer of underlayment felt applied shingle
fashion, parallel to and starting from the eaves and lapped 2 inches
(51 mm) , fastened sufficiently in place.
§RR905.3.3.3 Underlayment and high wind. Underlayment applied in
areas subject to high wind [greater than 110 miles per hour (177
km/h) per Figure RR301.2 (4) ] shall be applied with corrosion-
resistant fasteners in accordance with manufacturer's installation
instructions. Fasteners are to be applied along the overlap not
farther apart than 36 inches (914 mm) on center.
§RR905.3.4 Tile. Clay roof tile shall comply with ASTMC 1167.
§RR905.3.5 Concrete tile. Concrete roof tiles shall be in accordance
with the p cal test requirements as foil :
1. The transverse strength of tiles shall be determinedaccording
to Section 5.3 of ASTM C 1167 and in accordance with
Table RR905.3 .5.
2. The absorption of concrete roof tiles shall be according to
§8 of ASTM C 140. Roof tiles shall absorb not more than 15 percent
of the dry weight of the tile during a 24-hour immersion test.
3 . Roof tiles shall be tested for freeze/thaw resistanceaccording
to §8 of ASTM C 67 . Roof tiles shall show no breakage and not have
more than 1-percent loss in dry weight of any individual concrete
roof tile.
TABLE RR905.3.5
TRANSVERSE BREAKING STRENGTH OF
CONCRETE ROOF TILE
DRY (pounds)
AVERAGE OF
TILE PROFILE 5 TILES I INDIVIDUAL TILE
High profile 400 350
Medium profile 300 250
Flat profile 300 250
For SI: 1 pound = 4.45 N.
§RR905.3.6 Fasteners. Nails shall be corrosion-resistant and not less
than 11 gage, 5/16-inch (10.6 mm) head, and of sufficient length to
penetrate the deck a minimum of 3/4 inch (19.1 mm) or through the
thickness of the deck, whichever is less. Attaching wire for clay or
concrete tile shall not be smaller than 0.083 inch (2 .1 mm) . Perimeter
fastening areas include three tile courses but not less than 36 inches
(914 mm) from either side of hips or ridges and edges of eaves and
gable rakes.
§RR905.3.7 Application. Tile shall be applied in accordance with this
chapter and the manufacturer' s installation instructions, based on the
following:
1. Climatic conditions.
2. Roof slope.
3. Underlayment system.
4. Type of tile being installed.
Clay and concrete roof tiles shall be fastened in accordance with this
section and the manufacturer' s installation instructions. Perimeter
tiles shall be fastened with aminimum of one fastener per tile. Tiles
with installed weight less than 9 pounds per square foot (0.43 kN/m^2)
require a minimum of one fastener per tile regardless of roof slope.
Clay and concrete roof tile attachment shall be in accordance with the
manufacturer's installation instructions whereapplied in areas where the
wind speed exceeds 100 miles per hour (161 km/h) and on buildings where
the roof is located more than 40 feet (12 192 mm) above grade. In areas
subject to snow, a minimum of two fasteners per tile is required. In
all other areas, clay and concrete roof tiles shall be attached in
accordance with Table RR905 . 3 .7.
TABLE RR905.3 .7
CLAY AND CONCRETE TILE ATTACHMENT
OD NUMBER OF I
SHEATI I ROOF SLOPE FASTENERS I
Solid without battens All One per tile
Spaced or solid with
battens and Fasteners
slope < 5:12 not required --
5 :12 <= slope One per tile/every
Spaced sheathing < 12 :12 other row
without battens
12 :12 <= slope One per tile
< 24 :12
§RR905.3.8 Flashing. At the juncture of roof vertical surfaces,
flashing and counter flashing shall be provided in accordance with this
chapter and the manufacturer's installation instructions and, where of
metal, shall not be less than 0. 019 inch (0.48 mm) (No. 26 galvanized
shr'et gage) corrosion-resistant metal. The valley flashing shall
extend at least 11 inches (279 mm) from the center line each way and
have a splash diverter rib not less than 1 inch (25.4 mm) high at the
flow line formed as part of the flashing. Sections of flashing shall
have an end lap of not less than 4 inches (102 mm) . For roof slopes
of 3:12 and over, valley flashing shall have a 36-inch-wide (914 mm)
underlayment of one layer of Type I underlayment running the full
length of the valley, in addition to other required underlayment. In
areas where the average daily temperature in January is 25IF (-4IC) or
less, metal valley flashing underlayment shall be solid cemented to
the roofing underlayment for slopes under 7:12.
§RR905.4 Metal roof shingles. The installation of metal roof shingles
shall comply with the provisions of this section.
§RR905.4.1 Deck requirements. Metal roof shingles shall be applied to
a solid or closely fitted deck, except where the roof covering is
specifically designed to be applied to spaced sheathing.
§RR905.4.2 Deck slope. Metal roof shingles shall not be installed on
roof slopes below three units vertical in 12 units horizontal (25-
percent slope) .
§RR905.4.3 Underlayment. In areas where the average daily temperature
in January is 25IF (-4IC) or less, an ice barrier that consists of at
least two layers of underlayment cemented together or of a self-
adhering polymer modified bitumen sheet shall be used in lieu of normal
underlayment andextend from the eave's edge to a point at least 24
inches (610 mm) inside the exterior wall line of the building.
Underlayment shall comply with ASTM D 226, Type I.
§RR905.4.4 Material standards. Metal roof shingle roof coverings of
galvanized steel shall be 0 .013 inch (0.378 mm) minimum thickness.
Metal roof shingle roof coverings of aluminum shall be of 0.024 inch
(0 .610 mm) minimum thickness.
02R905.4.5 Application. Metal roof shingles shall be secured to the
roof in accordance with this chapter and the approved manufacturer's
installation instructions.
§RR905.4.6 Flashing. Roof valley flashing shall be provided of
corrosion-resistant metal of the same material as the roof covering or
shall comply with the standards in Table RR905 .10.3 . The valley
flashing shall extend at least 8 inches (203 mm) from the center line
each way and shall have a splash diverter rib not less than 3/4 inch
(19 .1 mm) high at the flow line formed as part of the flashing.
Sections of flashing shall have an end lap of not less than 4 inches
(102 mm) . The metal valley flashing shall have a 36-inch-wide (914 mm)
underlayment directly under it consisting of one layer of underlayment
running the Mil length of the valley, in ad on to underlayment
required for al roof shingles. In areas a the average daily
temperature in January is 25IF(-4IC) or less, the metal valley flashing
underlayment shall be solid cemented to the roofing underlayment for
roof slopes under seven units vertical in 12 units horizontal (58.3-
percent slope) or self-adhering polymer modified bitumen sheet.
§RR905.5 Mineral-surfaced roll roofing. The installation of mineral-
surfaced rolling roofing shall comply with this section.
§RR905.5.1 Deck requirements. Mineral-surfaced roll roofing shall be
fastened to solidly sheathed roofs.
§RR905.5.2 Deck slope. Mineral-surfaced roll roofing shall not be
applied on roof slopes below one unit vertical in12 units horizontal (8-
percent slope) .
§RR905.5.3 Underlayment. In areas where the average daily temperature
in January is 25IF (-4IC) or less, an ice barrier that consists of at
least two layers of underlayment cemented together or of a self-
adhering polymer modified bitumen sheet sh 11 extend from the eave's
edge to a point at least 24 inches (610 mm) inside the exterior wall
line of the building. Underlayment shall conform with ASTM D 226, Type
I.
§RR905.5.4 Material standards. Mineral-surfaced roll roofing shall
conform to ASTM D 224, D 249, D 371 or D 3909.
§RR905.5.5 Application. Mineral-surfaced roll roofing shall be
installed in accordance with this chapter and the manufacturer's
installation instructions.
§RR905.6 Slate and slate-type shingles. The installation of slate and
slate-type shingles shall comply with the provisions of this section.
§RR905.6.1 Deck requirements. Slate shingles shall be fastened to
solidly sheathed roofs.
§RR905.6.2 Deck slope. Slate shingles shall only be used on slopes of
four units vertical in 12 units horizontal- (33 -percent slope) or
greater.
§RR905.6.3 Underlayment. In areas where the average daily temperature
in January is 25IF (-4IC) or less, an ice barrier that consists of at
least two layers of underlayment cemented together or of a self-
adhering polymer modified bitumen sheet shall extend from the eave's
edge to a point at least 24 inches (610 mm) inside the exterior wall
line of the building. Underlayment shall comply with ASTM D 226, Type
II.
§RR905.6.4 Material standards. Slate shingles shall comply with ASTM
C 406.
§RR905.6.5 Application. Minimum headlap for slate shingles shall be in
accordance with Table RR905 . 6.5. Slate shingles shall be secured to
the roof with two fasteners per slate. Slate shingles shall be
installed in accordance with this chapter and the manufacturer's
installation instructions.
TABLE RR905.6.5
SLATE SHINGLE HEADLAP
SLOPE HEADLAP (inches)
4:12 <= slope < 8 :12 4
8:12 <= slope < 20:12 3
I sl >= 20:12
For SI: 1 inch = 25.4 mm.
§RR905.6.6 Flashing. Flashing and counterflashing shall be made with
sheet metal. Valley flashing shall be a minimum of 15 inches (381 mm)
wide. Valley and flashing metal shall be a minimum uncoated thickness
of 0.0179-inch (0.455 mm) zinc coated G90. Chimneys, stucco or brick
walls shall have a minimum of two plies of felt for a cap flashing
consisting of a 4-inch-wide (102 mm) strip of felt set in plastic
cement and extending 1 inch (25.4 mm) above the first felt and a top
coating of plastic cement. The felt shall extend over the base
flashing 2 inches (51 mm) .
§RR905.7 Wood shingles. The installation of wood shingles shall comply
with the provisions of this section.
§RR905.7.1 Deck requirements. Wood shingles shall be installed on
solid or spaced sheathing. Where spaced sheathing is used, sheathing
boards shall not be less than 1-inch by 4-inch (25.4 mm by 102 mm)
nominal dimensions and shall be spaced on centers equal to the weather
exposure to coincide with the placement of fasteners.
§RR905.7.1.1 Solid sheathing required. In areas where the average
daily temperature in January is 25IF (-4IC) or less, solid sheathing
is required on that portion of the roof requiring the application of
an ice shield.
§RR905.7.2 Deck slope. Wood shingles shall be installed on slopes of
three units vertical in 12 units horizontal (25-percent slope) or
greater.
§RR905.7.3 Underlayment. In areas where the average daily
temperature in January is 25IF (-4IC) or less, an ice barrier that
consists of at least two layers of underlayment cemented together or
of a self-adhering polymer modified bitumen sheet shall extend from
the eave's edge to a point at least 24 inches (610 mm) inside the
exterior wall line of the building. Underlayment shall comply with
ASTM D 226, Type I.
§RR905.7.4 Material standards. Wood shingles shall be of naturally
durable wood and comply with the requirements of Table RR905.7.4.
TABLE RR905.7.4
WOOD SHINGLE MATERIAL REQUIREMENTS
APPLICABLE
MATERIAL I MINIMUM GRADES GRADING RULES
Wood shingles of
naturally durable 1, 2 or 3 Cedar Shake and
wood Shingle Bureau
§RR905.7.5 Application. Wood shingles shall be installed according to
this chapter and the manufacturer's installation instructions. Wood
shingles shall be laid with a side lap not less than 1 1/2 inches (38
mm) between joints in courses, and no two joints in any three adjacent
courses shall be in direct alignment. Spacing between shingles shall
not be less than 1/4 inch to 3/8 inch (6.4 mm to 9.5 mm) . Weather
exposure for wood shingles shall not exceed those set in Table RR905.7.5.
Fasteners for wood shingles shall be corrosion-resistant with a minimum
penetration of 1/2 inch (12 .7 mm) into the sheathing. For sheathing less
than 1/2 inch (12 .7 mm) in thickness, the fasteners shall extend through
the sheathing. Wood shingles shall be attached to the roof with two
fasteners per shingle, positioned no more than 3/4 inch (19 .1 mm) from
each edge and no more than 1 inch (25 .4 mm) above the exposure line.
TABLE RR905.7.5
WOO•HINGLE WEATHER EXPOSURE AND R SLOPE{a}
EXPOSURE (inches)
ROOFING LENGTH 3:12 pitch I 4:12 pitch I
MATERIAL I (inches) I GRADE I to < 4:12 I or steeper
No. 1 3-3/4 5
16 No. 2 3-1/2 4
No. 3 3 3-1/2
Shingles of No. 1 4-1/4 5-1/2
naturally
durable wood 18 No. 2 4 4-1/2
No. 3 3-1/2 4
No. 1 5-3/4 7-1/2
24 No. 2 5-1/2 6-1/2
No. 3 5 5-1/2
For SI: 1 inch = 25.4 mm.
{a} For 24-inch by 3/8-inch handsplit shakes, the maximum exposure is 7-
1/2 inches for roof pitches of 4:12 and steeper only. (See §RR905.8.1. )
§RR905.7.6 Valley flashing. Roof flashing shall be not less than No.
26 gage [0.019 inches (0.48 mm) ] corrosion-resistant sheet metal and
shall extend 10 inches (254 mm) from the centerline each way for roofs
having slopes less than 12 units vertical in 12 units horizontal (100-
percent slope) , and 7 inches (178 mm) from the centerline each way for
slopes of 12 units vertical in 12 units horizontal and greater.
Sections of flashing shall have an end lap of not less than 4 inches
(102 mm) .
§RF905.7.7 Label required. Each bundle of shingles sha :-1 be identified
by a label of an approved grading or inspection bureau or agency.
§RR905.8 Wood shakes. The installation of wood shakes shall comply with
the provisions of this section.
§RR905.8.1 Deck requirements. Wood shakes shall only be used on solid
or spaced sheathing. Where spaced sheathing is used, sheathing boards
shall not be less than 1-inch by 4-inch (25.4 mm by 102 mm) nominal
dimensions and shall be spaced on centers equal to the weather exposure
to coincide with the placement of fasteners. Where 1-inch by 4-inch
(25.4 mm by 102 mm) spaced sheathing is installed at 10 inches (254 mm)
on center, additional 1-inch by 4-inch (25.4 mm by 102 mm) boards shall
be installed between the sheathing boards.
§RR905.8.1.1 Solid sheathing required. In areas where the average
daily temperature in January is 25IF (-4IC) or less, solid sheathing
is required on that portion of the roof requiring an ice barrier.
§RR905.8.2 Deck slope. Wood shakes shall only be used on slopes of
three units vertical in 12 units horizontal (25-percent slope) or
greater.
§RR905.8.3 Underlayment. In areas where the average daily temperature
in January is 25IF (-4IC) or less, an ice barrier that consists of at
least two layers of underlayment cemented together or a self-adhering
polymer modified bitumen sheet shall extend from the edge of the eave
to a point at least 24 inches (610 mm) inside the exterior wall line of
the building. Underlayment shall comply with ASTM D 226, Type I.
1 §RR905.8.4 Allayment. Interlayment shall lily with ASTM D 226,
1 Type I.
§RR905.8.5 Material standards. Wood shakes shall comply with the
requirements of Table §RR905. 8 .5.
TABLE RR905.8.5
WOOD SHAKE MATERIAL REQUIREMENTS
MINIMUM APPLICABLE
MATERIAL I GRADES I GRADING RULES
Wood shakes of naturally Cedar Shake and
durable wood 1 Shingle Bureau
Taper sawn shakes of Cedar Shake and
naturally durable wood 1 or 2 Shingle Bureau
Preservative-treated shakes
and shingles of naturally 1 Cedar Shake and
durable wood Shingle Bureau
Fire-retardant-treated shakes
and shingles of naturally 1 Cedar Shake and
durable wood Shingle Bureau
Preservative-treated tapersawn Forest Products
shakes of southern yellow pine 1 or 2 Laboratory of the
treated in accordance Texas Forest Services
with AWPA Standard C2
§RR905.8.6 Application. Wood shakes shall be installed according to
this chapter and the manufacturer's installation instructions. Wood
shakes shall be laid with a side lap not less than 1 1/2 inches (38 mm)
between joints in adjacent courses. Spacing between shakes in the same
course shall be 1/8 inch to 5/8 inch (3 .2 mm to 15.9 mm) for shakes and
tapersawn shakes of naturally durable wood and shall be 1/4 inch to 3/8
inch (6.4 mm to 9.5 mm) for preservative tapersawn shakes. Weather
exposure for wood shakes shall not- exceed those set forth in •
Table RR905.8.6. Fasteners for wood shakes shall be corrosion-
resistant, with a minimum penetration of 1/2 inch (12.7 mm) into the
sheathing. For sheathing less than 1/2 inch (12.7 mm) in thickness,
the fasteners shall extend through the sheathing. Wood shakes shall be
attached to the roof with two fasteners per shake, positioned no more
thanl inch (25.4 mm) from each edge and no more than 2 inches (51 mm)
above the exposure line.
TABLE RR905.8.6
WOOD SHAKE WEATHER EXPOSURE AND ROOF SLOPE
EXPOSURE (inches)
LENGTH
ROOFING MATERIAL ( (inches) 1 GRADE I 4:12 pitch or steeper'
Shakes of naturally 18 No. 1 7-1/2
durable wood
24 No. 1 10{a}
18 No. 1 7-1/2
Preservative-treated taper 24 No. 1 10
sawn shakes of
Southern Yellow Pine 18 No. 2 5-1/2
24 No. 2 7-1/2
18 No. 1 7-1/2
Taper-sawn shak f
naturally durabniood 24 No. 1 III 10
18 No. 2 5-1/2
24 No. 2 7-1/2
For SI: 1 inch = 25.4 mm.
{a} For 24-inch by 3/8-inch handsplit shakes, the maximum exposure is
7-1/2 inches.
§RR905.8.7 Shake placement. The starter course at the eaves shall be
doubled and the bottom layer shall be either 15-inch (381 mm) , 18-inch
(457 mm) or 24-inch (610 mm) wood shakes or wood shingles. Fifteen-inch
(381 mm) or 18-inch (457 mm) wood shakes may be used for the final
course at the ridge. Shakes shall be interlaid with 18-inch-wide (457
mm) strips of not less than No. 30 felt shingled between each course
in such a manner that no felt is exposed to the weather by positioning
the lower edge of each felt strip above the butt end of the shake it
covers a distance equal to twice the weather exposure.
§RR905.8.8 Valley flashing. Roof valley flashing shall not be less
than No. 26 gage [0.019 inches (0.48 mm) ] corrosion-resistant sheet
metal and shall extend at least 11 inches (279 mm) from the centerline
each way. Sections of flashing shall have an end lap of not less than 4
inches (102 mm) .
§RR905.8.9 Label required. Each bundle of shakes shall be identified
by a label of an approved grading or inspection bureau or agency.
§RR905.9 Built-up roofs. The installation of built-up roofs shall comply
with the provisions of this section.
§RR905.9.1 Slope. Built-up roofs shall have a design slope of a
minimum of one-fourth unit vertical in 12 units horizontal (2-percent
slope) for drainage, except for coal-tar built-up roofs, which shall
have a design slope of a minimum one-eighth unit vertical in 12 units
horizontal (1-percent slope) .
§RR905.9.2 Material standards. Built-up roof covering materials shall
comply with the standards in Table RR905 .9.2.
§RR905.9.3 Application. Built-up roofs shall be installedaccording to
this chapter and the manufacturer's installation instructions.
§RR905.10 Metal roof panels. The installation of metal roof panels
shall comply with the provisions of this section.
§RR905.10.1 Deck requirements. Metal roof panel roof coverings
shall be applied to a solid or spaced sheathing, except where the
roof covering is specifically designed to be applied to spaced
supports.
§RR905.10.2 Slope. The minimum slope for lapped, nonsoldered seam
metal roofs without applied lap sealant shall be three units vertical
in 12 units horizontal (25-percent slope) . The minimum slope for
lapped, nonsoldered seam metal roofs with applied lap sealant shall be
one-half vertical unit in 12 units horizontal (4-percent slope) . The
minimum slope for standing seam roof systems shall be one-fourth unit
vertical in 12 units horizontal (2-percent slope) .
§RR905.10.3 Material standards. Metal-sheet roof covering systems
that incorporate supporting structural members shall be designed in
accordance with the International Building Code. Metal-sheet roof
coverings installed over structural decking shall comply with
Table RR905 .10 .3 .
TABLE RR905.9.2
•UILT-UP ROOFING MATERIAL STANDS
{ I MATERIAL STANDARD STANDARD
Acrylic coatings used in roofing ASTM D 6083
Aggregate surfacing ASTM D 1863
Asphalt adhesive used in roofing ASTM D 3747
Asphalt cements used in roofing ASTM D 3019; D 2822; D 4586
Asphalt-coated glass fiber base sheet ASTM D 4601
Asphalt coatings used in roofing ASTM D 1227; D 2823; D 2824
D 4479
Asphalt glass felt ASTM D 2178
Asphalt primer used in roofing ASTM D 41
Asphalt-saturated and asphalt-coated ASTM D2626
organic felt base sheet
Asphalt-saturated organic felt ASTM D 226
(perforated)
Asphalt used in roofing ASTM D 312
Coal tar cements used in roofing ASTM D 4022; D 5643
Coal-tar saturated organic felt ASTM D 227
Coal-tar used in roofing ASTM D 450, Types I or II
Glass mat, coal tar ASTM D 4990
Glass mat, venting type ASTM D 4897
Mineral-surfaced inorganic cap sheet ASTM D 3909
Thermoplastic fabrics used in roofing ASTM D 5665; D 5726
TABLE RR905.10.3
METAL ROOF COVERINGS STANDARDS AND INSTALLATION
ROOF COVERING TYPE I STANDARD APPLICATION RATE/THICKNESS
Galvanized steel ASTM A 653 G-90 zinc coated, 0.013
inch thick minimum
Prepainted steel ASTM A 755
Aluminum zinc alloy coated steel ASTM A 792 AZ 50
Lead-coated copper ASTM B 101
Copper ASTM B 370, 16 oz. per sq. ft. for
metal sheet roof covering systems;
12 oz. per sq. ft. for preformed metal
shingle systems. CDA 4115
Hard lead 2 lbs. per sq. ft.
Soft lead 3 lbs. per sq. ft.
Aluminum 0 .024 inch minimum thickness
Terne (tin) and Sne coated Terne coating •40 lb. per double
stainless base box, field painted where
applicable in accordance with
manufacturer's installation
instructions .
For SI: 1 inch = 25.4 mm,
1 square foot = 0.0929 m^2,
1 pound = 0.454 kg,
1 ounce per square foot = 305 g/m^2,
1 pound per square foot = 0.0479 kN/m^2 .
§RR905.10.4 Attachment. Metal roofing shall be installed in
accordance with this chapter and the manufacturer's installation
instructions. Metal roofing fastened directly to steel framing shall
be attached by approved fasteners_ The following fasteners shall be
used:
1. Galvanized fasteners shall be used for galvanized roofs.
2 . Hard copper or copper allow shall be used for copper roofs.
3 . Stainless steel fasteners are acceptable for metal roofs.
§RR905.11 Modified bitumen roofing. The installation of modified
bitumen roofing shall comply with the provisions of this section.
§RR905.11.1 Slope. Modified bitumen membrane roofs shall have a
design slope of a minimum of one-fourth unit vertical in 12 units
horizontal (2-percent slope) for drainage.
•
0RR905.11.2 Material standards. Modified bitumen roof coverings shall
comply with the standards in Table RR905.11.2 .
TABLE RR905.11.2
MODIFIED BITUMEN ROOFING MATERIAL STANDARDS
MATERIAL STANDARD
Modified bitumen roof ASTM D 6162; D 6163; D 6164; D 6222;
membrane D 6223; CGSB 37-56M
Asphalt primer ASTM D 41
Asphalt cement ASTM D 3019
Asphalt adhesive ASTM D 3747
Asphalt coating ASTM D 1227; D 2824
Acrylic coating ASTM D 6083
§RR905.11.3 Application. Modified bitumen roofs shall be installed
according to this chapter and the manufacturer' s installation
instructions.
§RR905.12 Thermoset single-ply roofing. The installation of thermoset
single-ply roofing shall comply with the provisions of this section.
§RR905.12.1 Slope. Thermoset single-ply membrane roofs shall have a
design slope of a minimum of one-fourth unit vertical in 12 units
horizontal (2-percent slope) for drainage.
0RR905.12.2 Materials standards. Thermoset single-ply roof coverings
shall comply with RMA RP-1, RP-2 or RP-3, or ASTM D 4637 or CGSB 37-52M.
§RR905.12.3 Application. Thermoset single-ply roofs shall be
installed ac ing to this chapter and the facturer's installation
instructions.
Thermoplastic single-ply roofing. The installation of
thermoplastic single-ply roofing shall comply with the provisions of this
section.
§RR905.13 .1 Slope. Thermoplastic single-ply membrane roofs shall have
a design slope of a minimum of one-fourth unit vertical in 12 units
horizontal (2-percent slope) .
§RR905.13.2 Material standards. Thermoplastic single-ply roof coverings
shall comply with ASTM D 4434 or CGSB 37-54M.
§RR905.13.3 Application. Thermoplastic single-ply roofs shall be
installed according to this chapter and the manufacturer's installation
instructions.
§RR905.14 Sprayed polyurethane foam roofing. The installation of sprayed
polyurethane foam roofing shall comply with the provisions of this
section.
§RR905.14.1 Slope. Sprayed polyurethane foam roofs shall have a design
slope of a minimum of one-fourth unit vertical in 12 units horizontal
(2-percent slope) for drainage.
§RR905.14.2 Material standards. Spray-applied polyurethane-foam
insulation shall comply with ASTM C 1029.
§RR905.14.3 Application. Foamed in place roof insulation shall be
installed in accordance with this chapter and the manufacturer's
installation instructions. A liquid-applied protective coating that
complies with §RR905.15 shall be applied no less than 2 hours nor more
than 72 hours following the application of the foam.
§RR905.14.4 Foam plastics. Foam plastic materials and installation
shall comply with §RR318.
§RR905.15 Liquid-applied coatings. The installation of liquid-applied
coatings shall comply with the provisions of this section.
§RR905.15.1 Slope. Liquid-applied roofs shall have a design slope of a
minimum of one-fourth unit vertical in 12 units horizontal (2-percent
slope) .
§RR905.15.2 Material standards. Liquid-applied roof coatings shall
comply with ASTM C 836, C 957, D 1227, D 3468 or D 6083.
§RR905.15.3 Application. Liquid-applied roof coatings shall be
installed according to this chapter and the manufacturer's installation
instructions.