The provisions of this chapter shall control the design and construction of the interior and exterior wall covering for all buildings.
Interior coverings or wall finishes shall be installed in accordance with this chapter and Table R702.1(1), Table R702.1(2), Table R702.1(3) and Table R702.3.5. Interior masonry veneer shall comply with the requirements of Section R703.7.1 for support and Section R703.7.4 for anchorage, except an air space is not required. Interior finishes and materials shall conform to the flame spread and smoke-development requirements of Section R302.9.
TABLE R702.1(1)
THICKNESS OF PLASTER
| PLASTER BASE | FINISHED THICKNESS OF PLASTER FROM FACE OF LATH, MASONRY, CONCRETE (inches) | |
| Gypsum Plaster | Cement Plaster | |
| Expanded metal lath | 5/8, minimuma | 5/8, minimuma |
| Wire lath | 5/8, minimuma | 3/4, minimum (interior)b |
| 7/8, minimum (exterior)b | ||
| Gypsum lathg | 1/2, minimum | 3/4, minimum (interior)b |
| Masonry wallsc | 1/2, minimum | 1/2, minimum |
| Monolithic concrete wallsc, d | 5/8, maximum | 7/8, maximum |
| Monolithic concrete ceilingsc, d | 3/8, maximume | 1/2, maximum |
| Gypsum veneer basef, g | 1/16, minimum | 3/4, minimum (interior)b |
| Gypsum sheathingg | — | 3/4, minimum (interior)b |
| 7/8, minimum (exterior)b | ||
TABLE R702.1(2)
GYPSUM PLASTER PROPORTIONSa
| NUMBER | COAT | PLASTER BASE OR LATH | MAXIMUM VOLUME AGGREGATE PER 100 POUNDS NEAT PLASTERb (cubic feet) | |
| Damp Loose Sanda | Perlite or Vermiculitec | |||
| Two-coat work | Base coat | Gypsum lath | 2.5 | 2 |
| Base coat | Masonry | 3 | 3 | |
| Three-coat work | First coat | Lath | 2d | 2 |
| Second coat | Lath | 3d | 2e | |
| First and second coats | Masonry | 3 | 3 | |
TABLE R702.1(3)
CEMENT PLASTER PROPORTIONS, PARTS BY VOLUME
| COAT | CEMENT PLASTER TYPE | CEMENTITIOUS MATERIALS | VOLUME OF AGGREGATE PER SUM OF SEPARATE VOLUMES OF CEMENTITIOUS MATERIALSb | |||
| Portland Cement Type I, II or III or Blended Cement Type IP,I (PM), IS or I (SM) | Plastic Cement | Masonry Cement Type M, S or N | Lime | |||
| First | Portland or blended | 1 | 3/4 - 11/2a | 21/2- 4 | ||
| Masonry | 1 | 21/2- 4 | ||||
| Plastic | 1 | 21/2- 4 | ||||
| Second | Portland or blended | 1 | 3/4 - 11/2 | 3 -5 | ||
| Masonry | 1 | 3 -5 | ||||
| Plastic | 1 | 3- 5 | ||||
| Finish | Portland or blended | 1 | 3/4- 2 | 11/2 -3 | ||
| Masonry | 1 | 11/2- 3 | ||||
| Plastic | 1 | 11/2- 3 | ||||
Cement plaster materials shall conform to ASTM C 91 (Type M, S or N), C 150 (Type I, II and III), C 595 [Type IP, I (PM), IS and I (SM), C 847, C 897, C 926, C 933, C 1032, C 1047 and C 1328, and shall be installed or applied in compliance with ASTM C 1063. Gypsum lath shall conform to ASTM C 1396. Plaster shall not be less than three coats when applied over metal lath and not less than two coats when applied over other bases permitted by this section, except that veneer plaster may be applied in one coat not to exceed 3/16 inch (4.76 mm) thickness, provided the total thickness is in accordance with Table R702.1(1).
R702.2.2.1 Application.Each coat shall be kept in a moist condition for at least 24 hours prior to application of the next coat.
The finish coat for two-coat cement plaster shall not be applied sooner than 48 hours after application of the first coat. For three coat cement plaster the second coat shall not be applied sooner than 24 hours after application of the first coat. The finish coat for three-coat cement plaster shall not be applied sooner than 48 hours after application of the second coat.
Maximum spacing of supports and the size and spacing of fasteners used to attach gypsum board shall comply with Table R702.3.5. Gypsum sheathing shall be attached to exterior walls in accordance with Section R602. Gypsum board shall be applied at right angles or parallel to framing members. All edges and ends of gypsum board shall occur on the framing members, except those edges and ends that are perpendicular to the framing members. Interior gypsum board shall not be installed where it is directly exposed to the weather or to water.
TABLE R702.3.5
MINIMUM THICKNESS AND APPLICATION OF GYPSUM BOARD
| THICKNESS OF GYPSUM BOARD (inches) | APPLICATION | ORIENTATION OF GYPSUM BOARD TO FRAMING | MAXIMUM SPACING OF FRAMING MEMBERS (inches o.c.) | MAXIMUM SPACING OF FASTENERS (inches) | SIZE OF NAILS FOR APPLICATION TO WOOD FRAMINGc | |
| Nailsa | Screwsb | |||||
| Application without adhesive | ||||||
| 3/8 | Ceilingd | Perpendicular | 16 | 7 | 12 | 13 gage, 11/4″ long, 19/64″ head; 0.098″ diameter, 11/4″ long, annular-ringed; or 4d cooler nail, 0.080″ diameter, 13/8″ long, 7/32″ head. |
| Wall | Either direction | 16 | 8 | 16 | ||
| 1/2 | Ceiling | Either direction | 16 | 7 | 12 | 13 gage, 13/8″ long, 19/64″ head; 0.098″ diameter, 11/4″ long, annular-ringed; 5d cooler nail, 0.086″ diameter, 15/8″ long, 15/64″ head; or gypsum board nail, 0.086″ diameter, 15/8″ long, 9/32″ head. |
| Ceilingd | Perpendicular | 24 | 7 | 12 | ||
| Wall | Either direction | 24 | 8 | 12 | ||
| Wall | Either direction | 16 | 8 | 16 | ||
| 5/8 | Ceiling | Either direction | 16 | 7 | 12 | 13 gage, 15/8″ long, 19/64″ head; 0.098″ diameter, 13/8″ long, annular-ringed; 6d cooler nail, 0.092″ diameter, 17/8″ long, 1/4″ head; or gypsum board nail, 0.0915″ diameter, 17/8″ long, 19/64″ head. |
| Ceilinge | Perpendicular | 24 | 7 | 12 | ||
| Wall | Either direction | 24 | 8 | 12 | ||
| Wall | Either direction | 16 | 8 | 16 | ||
| Application with adhesive | ||||||
| 3/8 | Ceilingd | Perpendicular | 16 | 16 | 16 | Same as above for 3/8″ gypsum board |
| Wall | Either direction | 16 | 16 | 24 | ||
| 1/2 or 5/8 | Ceiling | Either direction | 16 | 16 | 16 | Same as above for 1/2″ and 5/8″ gypsum board, respectively |
| Ceilingd | Perpendicular | 24 | 12 | 16 | ||
| Wall | Either direction | 24 | 16 | 24 | ||
| Two 3/8 layers | Ceiling | Perpendicular | 16 | 16 | 16 | Base ply nailed as above for 1/2″ gypsum board; face ply installed with adhesive |
| Wall | Either direction | 24 | 24 | 24 | ||
Use of gypsum board shall be permitted on wood joists to create a horizontal diaphragm in accordance with Table R702.3.7. Gypsum board shall be installed perpendicular to ceiling framing members. End joints of adjacent courses of board shall not occur on the same joist. The maximum allowable diaphragm proportions shall be 11/2:1 between shear resisting elements. Rotation or cantilever conditions shall not be permitted. Gypsum board shall not be used in diaphragm ceilings to resist lateral forces imposed by masonry or concrete construction. All perimeter edges shall be blocked using wood members not less than 2-inch by 6-inch (51 mm by 152 mm) nominal dimension. Blocking material shall be installed flat over the top plate of the wall to provide a nailing surface not less than 2 inches (51 mm) in width for the attachment of the gypsum board.
TABLE R702.3.7
SHEAR CAPACITY FOR HORIZONTAL WOOD-FRAMED
GYPSUM BOARD DIAPHRAGM CEILING ASSEMBLIES
| MATERIAL | THICKNESS OF MATERIAL (min.) (inch) | SPACING OF FRAMING MEMBERS (max.) (inch) | SHEAR VALUEa, b (plf of ceiling) | MINIMUM FASTENER SIZEc, d |
| Gypsum board | 1/2 | 16 o.c. | 90 | 5d cooler or wallboard nail; 15/8-inch long; 0.086- inch shank; 15/64-inch head |
| Gypsum board | 1/2 | 24 o.c. | 70 | 5d cooler or wallboard nail; 15/8-inch long; 0.086- inch shank; 15/64-inch head |
Gypsum board used as the base or backer for adhesive application of ceramic tile or other required nonabsorbent finish material shall conform to ASTM C 1396, C 1178 or C1278. Use of water-resistant gypsum backing board shall be permitted on ceilings where framing spacing does not exceed 12 inches (305 mm) on center for 1/2-inch-thick (12.7 mm) or 16 inches (406 mm) for 5/8-inch-thick (16 mm) gypsum board. Water-resistant gypsum board shall not be installed over a Class I or II vapor retarder in a shower or tub compartment. Cut or exposed edges, including those at wall intersections, shall be sealed as recommended by the manufacturer.
R702.3.8.1 Limitations.Water resistant gypsum backing board shall not be used where there will be direct exposure to water, or in areas subject to continuous high humidity.
Class I or II vapor retarders are required on the interior side of frame walls in Climate Zones 5, 6, 7, 8 and Marine 4.
1. Basement walls.
2. Below grade portion of any wall.
3. Construction where moisture or its freezing will not damage the materials.
Class III vapor retarders shall be permitted where any one of the conditions in Table R702.7.1 is met.
TABLE R702.7.1
CLASS III VAPOR RETARDERS
| CLIMATE ZONE | CLASS III VAPOR RETARDERS PERMITTED FOR:a |
| Marine 4 | Vented cladding over wood structural panels. |
| Vented cladding over fiberboard. | |
| Vented cladding over gypsum. | |
| Insulated sheathing with R-value ≥ 2.5 over 2 × 4 wall. | |
| Insulated sheathing with R-value ≥ 3.75 over 2 × 6 wall. | |
| 5 | Vented cladding over wood structural panels. |
| Vented cladding over fiberboard. | |
| Vented cladding over gypsum. | |
| Insulated sheathing with R-value ≥ ?5 over 2 × 4 wall. | |
| Insulated sheathing with R-value ≥ ?7.5 over 2 × 6 wall. | |
| 6 | Vented cladding over fiberboard. |
| Vented cladding over gypsum. | |
| Insulated sheathing with R-value ≥ ?7.5 over 2 × 4 wall. | |
| Insulated sheathing with R-value ≥ ?11.25 over 2 × 6 wall. | |
| 7 and 8 | Insulated sheathing with R-value ≥ ?10 over 2 × 4 wall. |
| Insulated sheathing with R-value ≥ ?15 over 2 × 6 wall. |
The vapor retarder class shall be based on the manufacturer’s certified testing or a tested assembly.
For the purposes of this section, vented cladding shall include the following minimum clear air spaces. Other openings with the equivalent vent area shall be permitted.
1. Vinyl lap or horizontal aluminum siding applied over a weather resistive barrier as specified in Table R703.4.
2. Brick veneer with a clear airspace as specified in Table R703.7.4.
3. Other approved vented claddings.
The exterior wall envelope shall be designed and constructed in a manner that prevents the accumulation of water within the wall assembly by providing a water-resistant barrier behind the exterior veneer as required by Section R703.2 and a means of draining to the exterior water that enters the assembly. Protection against condensation in the exterior wall assembly shall be provided in accordance with Section R702.7 of this code.
1. A weather-resistant exterior wall envelope shall not be required over concrete or masonry walls designed in accordance with Chapter 6 and flashed according to Section R703.7 or R703.8.
2. Compliance with the requirements for a means of drainage, and the requirements of Sections R703.2 and R703.8, shall not be required for an exterior wall envelope that has been demonstrated to resist wind-driven rain through testing of the exterior wall envelope, including joints, penetrations and intersections with dissimilar materials, in accordance with ASTM E 331 under the following conditions:
2.1. Exterior wall envelope test assemblies shall include at least one opening, one control joint, one wall/eave interface and one wall sill. All tested openings and penetrations shall be representative of the intended end-use configuration.
2.2. Exterior wall envelope test assemblies shall be at least 4 feet by 8 feet (1219 mm by 2438 mm) in size.
2.3. Exterior wall assemblies shall be tested at a minimum differential pressure of 6.24 pounds per square foot (299 Pa).
2.4. Exterior wall envelope assemblies shall be subjected to the minimum test exposure for a minimum of 2 hours.
One layer of No. 15 asphalt felt, free from holes and breaks, complying with ASTM D 226 for Type 1 felt or other approved water-resistive barrier shall be applied over studs or sheathing of all exterior walls. Such felt or material shall be applied horizontally, with the upper layer lapped over the lower layer not less than 2 inches (51 mm). Where joints occur, felt shall be lapped not less than 6 inches (152 mm). The felt or other approved material shall be continuous to the top of walls and terminated at penetrations and building appendages in a manner to meet the requirements of the exterior wall envelope as described in Section R703.1.
1. In detached accessory buildings.
2. Under exterior wall finish materials as permitted in Table R703.4.
3. Under paperbacked stucco lath when the paper backing is an approved water-resistive barrier.
Unless specified otherwise, all wall coverings shall be securely fastened with approved aluminum, stainless steel, zinc-coated or other approved corrosionresistive fasteners. Where wind pressures determined in accordance with Table R301.2(2), adjusted for height and exposure in accordance with Table R301.2(3), do not exceed 30 psf, wall coverings are permitted to be installed in accordance with Table R703.4.
TABLE R703.4
WEATHER–RESISTANT SIDING ATTACHMENT AND MINIMUM THICKNESS
| SIDING MATERIAL | NOMINAL THICKNESSa (inches) | JOINT TREATMENT | WATER- RESISTIVE BARRIER REQUIRED | TYPE OF SUPPORTS FOR THE SIDING MATERIAL AND FASTENERSb, c, d | |||||||
| Wood or wood structural panel sheathing into stud | Fiberboard sheathing into stud | Gypsum sheathing into stud | Foam plastic sheathing into stud | Direct to studs | Number or spacing of fasteners | ||||||
| Horizonal aluminume | Without insulation | 0.019f | Lap | Yes | 0.120 nail 11/2″ long | 0.120 nail 2″ long | 0.120 nail 2″ long | 0.120 naily | Not allowed | Same as stud spacing | |
| 0.024 | Lap | Yes | 0.120 nail 11/2″ long | 0.120 nail 2″ long | 0.120 nail 2″ long | 0.120 naily | Not allowed | ||||
| With insulation | 0.019 | Lap | Yes | 0.120 nail 11/2″ long | 0.120 nail 21/2″ long | 0.120 nail 21/2″ long | 0.120 naily | 0.120 nail 11/2″ long | |||
| Anchored veneer: brick, concrete, masonry or stone | 2 | Section R703 | Yes | See Section R703 and Figure R703.7g | |||||||
| Adhered veneer:concrete, stone or masonryw | — | Section R703 | Yes Note w | See Section R703.6.1g or in accordance with the manufacturer’s instructions. | |||||||
| Hardboardk Panel siding-vertical | See Section R703.3.3 | — | Yes | See SectionR703.3.4 | |||||||
| Hardboardk Lap-siding-horizontal | See Section R703.3.3 | Note q | Yes | See SectionR703.3.4 | |||||||
| Steelh | 29 ga. | Lap | Yes | 0.113 nail 13/4″ | 0.113 nail 23/4″ | 0.113 nail 21/2″ | 0.113 nailv | Not allowed | Same as stud spacing | ||
| Wood structural paneli ANSI/APA-PRP 210 sidingi (exterior grade) | 3/8 – 1/2 | Note p | Yes | 0.099 nail–2″ | 0.113 nail–21/2″ | 0.113 nail–21/2″ | 0.113 nailv | 0.099 nail–2″ | 6″ panel edges, 12″ inter. sup. | ||
| Wood structural panel lapsiding | 3/8 – 1/2 | Note p Note x | Yes | 0.099 nail–2″ | 0.113 nail–21/2″ | 0.113 nail–21/2″ | 0.113 nailx | 0.099 nail–2″ | 8″ along bottom edge | ||
| Vinyl sidingl | 0.035 | Lap | Yes | See SectionR703.11 | |||||||
| Woodj rustic, drop | 3/8 Min | Lap | Yes | Fastener penetration into stud-1″ | 0.113 nail-21/2″ | Face nailing up to 6″ widths, 1 nail per bearing; 8″ widths and over, 2 nails per bearing | |||||
(continued)
TABLE R703.4—continued
WEATHER–RESISTANT SIDING ATTACHMENT AND MINIMUM THICKNESS
| SIDING MATERIAL | NOMINAL THICKNESSa (inches) | JOINT TREATMENT | WATER- RESISTIVE BARRIER REQUIRED | TYPE OF SUPPORTS FOR THE SIDING MATERIAL AND FASTENERSb, c, d | |||||||
| Wood or wood structural panel sheathing into stud | Fiberboard sheathing into stud | Gypsum sheathing into stud | Foam plastic sheathing into stud | Direct to studs | Number or spacing of fasteners | ||||||
| Shiplap | 19/32 Average | Lap | Yes | Fastener penetration into stud–1″ | 0.113 nail–21/2″ | Face nailing up to 6″ widths, 1 nail per bearing; 8″ widths and over, 2 nails per bearing | |||||
| Bevel | 7/16 | ||||||||||
| Butt tip | 3/16 | Lap | Yes | ||||||||
| Fiber cement panel sidingq | 5/16 | Note q | Yes Note u | 6d common corrosion- resistant nailr | 6d common corrosion- resistant nailr | 6d common corrosion- resistant nailr | 6d common corrosion- resistant nailr, v | 4d common corrosion- resistant nailr | 6″ o.c. on edges, 12″ o.c. on intermed. studs | ||
| Fiber cement lap sidings | 5/16 | Note s | Yes Note u | 6d common corrosion- resistant nailr | 6d common corrosion- resistant nailr | 6d common corrosion- resistant nailr | 6d common corrosion- resistant nailr, v | Note w | |||
The maximum weather exposure for shakes and shingles shall not exceed that specified in Table R703.5.2.
TABLE R703.5.2
MAXIMUM WEATHER EXPOSURE FOR WOOD SHAKES AND SHINGLES ON EXTERIOR WALLSa, b, c
(Dimensions are in inches)
| LENGTH | EXPOSURE FOR SINGLE COURSE | EXPOSURE FOR DOUBLE COURSE |
| Shinglesa | ||
| 16 | 71/2 | 12b |
| 18 | 81/2 | 14c |
| 24 | 111/2 | 16 |
| Shakesa | ||
| 18 | 81/2 | 14 |
| 24 | 111/2 | 18 |
Wood shakes and shingles, and attachment and supports shall be capable of resisting the wind pressures determined in accordance with Table R310.2(2).Where wind pressures determined in accordance with Table R301.2(2) do not exceed 30 psf, each shake or shingle shall be held in place by two hot-dipped zinc-coated, stainless steel, or aluminum nails or staples. The fasteners shall be long enough to penetrate the sheathing or furring strips by a minimum of 1/2 inch (13 mm) and shall not be overdriven.Where pressures determined in accordance with Table R301.2(2) exceed 30 psf, the attachment shall be designed to resist the prescribed wind pressures.
R703.5.3.1 Staple attachment.Reserved.
Plastering with portland cement plaster shall be not less than three coats when applied over metal lath or wire lath and shall be not less than two coats when applied over masonry, concrete, pressure-preservative treated wood or decay-resistant wood as specified in Section R317.1 or gypsum backing. If the plaster surface is completely covered by veneer or other facing material or is completely concealed, plaster application need be only two coats, provided the total thickness is as set forth in Table R702.1(1).
A minimum 0.019-inch (0.5 mm) (No. 26 galvanized sheet gage), corrosion-resistant weep screed or plastic weep screed, with a minimum vertical attachment flange of 31/2 inches (89 mm) shall be provided at or below the foundation plate line on exterior stud walls in accordance with ASTM C 926. The weep screed shall be placed a minimum of 4 inches (102 mm) above the earth or 2 inches (51 mm) above paved areas and shall be of a type that will allow trapped water to drain to the exterior of the building. The weather-resistant barrier shall lap the attachment flange. The exterior lath shall cover and terminate on the attachment flange of the weep screed.
Water-resistive barriers shall be installed as required in Section R703.2 and, where applied over wood-based sheathing, shall include a water-resistive vapor-permeable barrier with a performance at least equivalent to two layers of Grade D paper. The individual layers shall be installed independently such that each layer provides a separate continuous plane and any flashing (installed in accordance with Section R703.8) intended to drain to the water-resistive barrier is directed between the layers.
Each coat shall be kept in a moist condition for at least 48 hours prior to application of the next coat.
Stone and masonry veneer shall be installed in accordance with this chapter, Table R703.4 and Figure R703.7. These veneers installed over a backing of wood or cold-formed steel shall be limited to the first story above-grade plane and shall not exceed 5 inches (127 mm) in thickness. See Section R602.3 for wall bracing requirements for masonry veneer for woodframed construction and Section R301.2.1 for wall bracing requirements for masonry veneer for cold-formed steel construction. The provisions of this section are limited to areas where the Vasd as determined in accordance with Section R301.2.1.3, is equal to or less than 130 mph.
1. For all buildings in Seismic Design Categories A, B and C, exterior stone or masonry veneer, as specified in Table R703.7(1), with a backing of wood or steel framing shall be permitted to the height specified in Table R703.7(1) above a noncombustible foundation.
2. For detached one- or two-family dwellings in Seismic Design Categories D0, D1 and D2, exterior stone or masonry veneer, as specified in Table R703.7(2), with a backing of wood framing shall be permitted to the height specified in Table R703.7(2) above a noncombustible foundation.
FIGURE R703.7
MASONRY VENEER WALL DETAILS
(continued)
FIGURE R703.7—continued
MASONRY VENEER WALL DETAILS
TABLE R703.7(1)
STONE OR MASONRY VENEER LIMITATIONS AND REQUIREMENTS,
WOOD OR STEEL FRAMING, SEISMIC DESIGN CATEGORIES A, B AND C
| SEISMIC DESIGN CATEGORY | NUMBER OF WOOD OR STEELFRAMED STORIES | MAXIMUM HEIGHT OF VENEER ABOVE NONCOMBUSTIBLE FOUNDATIONa (feet) | MAXIMUM NOMINAL THICKNESS OF VENEER (inches) | MAXIMUM WEIGHT OF VENEER (psf)b | WOOD OR STEELFRAMED STORY |
| A or B | Steel: 1 or 2 Wood: 1, 2 or 3 | 30 | 5 | 50 | all |
| C | 1 | 30 | 5 | 50 | 1 only |
| 2 | 30 | 5 | 50 | top | |
| bottom | |||||
| Wood only: 3 | 30 | 5 | 50 | top | |
| middle | |||||
| bottom |
TABLE R703.7(2)
STONE OR MASONRY VENEER LIMITATIONS AND REQUIREMENTS,
ONE- AND TWO-FAMILY DETACHED DWELLINGS, WOOD FRAMING, SEISMIC DESIGN CATEGORIES D0, D1 AND D2
| SEISMIC DESIGN CATEGORY | NUMBER OF WOOD FRAMED STORIESa | MAXIMUM HEIGHT OF VENEER ABOVE NONCOMBUSTIBLE FOUNDATION OR FOUNDATION WALL (feet) | MAXIMUM NOMINAL THICKNESS OF VENEER (inches) | MAXIMUM WEIGHT OF VENEER (psf)b |
| D0 | 1 | 20c | 4 | 40 |
| 2 | 20c | 4 | 40 | |
| 3 | 30d | 4 | 40 | |
| D1 | 1 | 20c | 4 | 40 |
| 2 | 20c | 4 | 40 | |
| 3 | 20c | 4 | 40 | |
| D2 | 1 | 20c | 3 | 30 |
| 2 | 20c | 3 | 30 |
Except in Seismic Design Categories D0, D1 and D2, exterior masonry veneers having an installed weight of 40 pounds per square foot (195 kg/m2) or less shall be permitted to be supported on wood or cold-formed steel construction. When masonry veneer supported by wood or cold-formed steel construction adjoins masonry veneer supported by the foundation, there shall be a movement joint between the veneer supported by the wood or cold-formed steel construction and the veneer supported by the foundation. The wood or cold-formed steel construction supporting the masonry veneer shall be designed to limit the deflection to 1/600 of the span for the supporting members. The design of the wood or cold-formed steel construction shall consider the weight of the veneer and any other loads.
R703.7.2.1 Support by steel angle.A minimum 6 inches by 4 inches by 5/16 inch (152 mm by 102 mm by 8 mm) steel angle, with the long leg placed vertically, shall be anchored to double 2 inches by 4 inches (51 mm by 102 mm) wood studs at a maximum on-center spacing of 16 inches (406 mm). Anchorage of the steel angle at every double stud spacing shall be a minimum of two 7/16 inch (11 mm) diameter by 4 inch (102 mm) lag screws. The steel angle shall have a minimum clearance to underlying construction of 1/16 inch (2 mm). A minimum of two-thirds the width of the masonry veneer thickness shall bear on the steel angle. Flashing and weep holes shall be located in the masonry veneer wythe in accordance with Figure R703.7.2.1. The maximum height of masonry veneer above the steel angle support shall be 12 feet, 8 inches (3861 mm). The air space separating the masonry veneer from the wood backing shall be in accordance with Sections R703.7.4 and R703.7.4.2. The method of support for the masonry veneer on wood construction shall be constructed in accordance with Figure R703.7.2.1.
FIGURE R703.7.2.1
EXTERIOR MASONRY VENEER SUPPORT BY STEEL ANGLES
A steel angle shall be placed directly on top of the roof construction. The roof supporting construction for the steel angle shall consist of a minimum of three 2 inch by 6 inch (51 mm by 152 mm) wood members. The wood member abutting the vertical wall stud construction shall be anchored with a minimum of three 5/8-inch (16 mm) diameter by 5-inch (127 mm) lag screws to every wood stud spacing. Each additional roof member shall be anchored by the use of two 10d nails at every wood stud spacing. A minimum of two-thirds the width of the masonry veneer thickness shall bear on the steel angle. Flashing and weep holes shall be located in the masonry veneer wythe in accordance with Figure R703.7.2.2. The maximum height of the masonry veneer above the steel angle support shall be 12 feet, 8 inches (3861 mm). The air space separating the masonry veneer from the wood backing shall be in accordance with Sections R703.7.4 and R703.7.4.2. The support for the masonry veneer on wood construction shall be constructed in accordance with Figure R703.7.2.2.
FIGURE R703.7.2.2
EXTERIOR MASONRY VENEER SUPPORT BY ROOF MEMBERS
Masonry veneer shall not support any vertical load other than the dead load of the veneer above. Veneer above openings shall be supported on lintels of noncombustible materials. The lintels shall have a length of bearing not less than 4 inches (102 mm). Steel lintels shall be shop coated with a rust-inhibitive paint, except for lintels made of corrosion-resistant steel or steel treated with coatings to provide corrosion resistance. Construction of openings shall comply with either Section R703.7.3.1 or 703.7.3.2.
R703.7.3.1 Allowable span.The allowable span shall not exceed the values set forth in Table R703.7.3.1.
TABLE R703.7.3.1
ALLOWABLE SPANS FOR LINTELS SUPPORTING MASONRY VENEERa, b, c, d
| SIZE OF STEEL ANGLEa, c, d (inches) | NO STORY ABOVE | ONE STORY ABOVE | TWO STORIES ABOVE | NO. OF 1/2-INCH OR EQUIVALENT REINFORCING BARS IN REINFORCED LINTELb, d |
| 3 × 3 × 1/4 | 6'-0″ | 4'-6″ | 3'-0″ | 1 |
| 4 × 3 × 1/4 | 8'-0″ | 6'-0″ | 4'-6″ | 1 |
| 5 × 31/2 × 5/16 | 10'-0″ | 8'-0″ | 6'-0″ | 2 |
| 6 × 31/2 × 5/16 | 14'-0″ | 9'-6″ | 7'-0″ | 2 |
| 2-6 × 31/2 × 5/16 | 20'-0″ | 12'-0″ | 9'-6″ | 4 |
The allowable span shall not exceed 18 feet 3 inches (5562 mm) and shall be constructed to comply with Figure R703.7.3.2 and the following:
1. Provide a minimum length of 18 inches (457 mm) of masonry veneer on each side of opening as shown in Figure R703.7.3.2.
2. Provide a minimum 5-inch by 31/2-inch by 5/16-inch (127 mm by 89 mm by 7.9 mm) steel angle above the opening and shore for a minimum of 7 days after installation.
3. Provide double-wire joint reinforcement extending 12 inches (305 mm) beyond each side of the opening. Lap splices of joint reinforcement a minimum of 12 inches (305 mm). Comply with one of the following:
3.1. Double-wire joint reinforcement shall be 3/16-inch (4.8 mm) diameter and shall be placed in the first two bed joints above the opening.
3.2. Double-wire joint reinforcement shall be 9 gauge (0.144 inch or 3.66 mm diameter) and shall be placed in the first three bed joints above the opening.
4. Provide the height of masonry veneer above opening, in accordance with Table R703.7.3.2.
TABLE R703.7.3.2
HEIGHT OF MASONRY VENEER ABOVE OPENING
| MINIMUM HEIGHT OF MASONRY VENEER ABOVE OPENING (INCH) | MAXIMUM HEIGHT OF MASONRY VENEER ABOVE OPENING (FEET) |
| 13 | < 5 |
| 24 | 5 to < 12 |
| 60 | 12 to height above support allowed by Section R703.7 |
FIGURE R703.7.3.2
MASONRY VENEER OPENING
Masonry veneer shall be anchored to the supporting wall studs with corrosion-resistant metal ties embedded in mortar or grout and extending into the veneer a minimum of 11/2 inches (38 mm), with not less than 5/8-inch (15.9 mm) mortar or grout cover to outside face. Masonry veneer shall conform to Table R703.7.4.
TABLE R703.7.4
TIE ATTACHMENT AND AIR SPACE REQUIREMENTS
| BACKING AND TIE | MINIMUM TIE | MINIMUM TIE FASTENERa | AIR SPACE | |
| Wood stud backing with corrugated sheet metal | 22 U.S. gage (0.0299 in.) × 7/8 in. wide | 8d common nail b (21/2 in. × 0.131 in.) | Nominal 1 in. between sheathing and veneer | |
| Wood stud backing with metal strand wire | W1.7 (No. 9 U.S. gage; 0.148 in.) with hook embedded in mortar joint | 8d common nail b (21/2 in. × 0.131 in.) | Minimum nominal 1 in. between sheathing and veneer | Maximum 41/2 in. between backing and veneer |
| Cold-formed steel stud backing with adjustable metal strand wire | W1.7 (No. 9 U.S. gage; 0.148 in.) with hook embedded in mortar joint | No. 10 screw extending through the steel framing a minimum of three exposed threads | Minimum nominal 1 in. between sheathing and veneer | Maximum 41/2 in. between backing and veneer |
Veneer ties, if strand wire, shall not be less in thickness than No. 9 U.S. gage [(0.148 inch) (4 mm)] wire and shall have a hook embedded in the mortar joint, or if sheet metal, shall be not less than No. 22 U.S. gage by [(0.0299 inch) (0.76 mm)] 7/8 inch (22 mm) corrugated. Each tie shall support not more than 2.67 square feet (0.25 m2) of wall area and shall be spaced not more than 32 inches (813 mm) on center horizontally and 24 inches (635 mm) on center vertically.
1. In Seismic Design Category D0, D1 or D2 or townhouses in Seismic Design Category C or in wind areas of more than 30 pounds per square foot pressure (1.44 kPa), each tie shall support not more than 2 square feet (0.2 m2) of wall area.
2. Where the Vasd, as determined in accordance with Section R301.2.1.3, exceeds 110 mph (176.99 km/h) or is less than or equal to 130 mph (208 km/h), each tie shall support not more than 1.8 square feet (0.167 m2) of wall area and anchors shall be spaced at a maximum 18 inches (457 mm) horizontally and vertically.
R703.7.4.1.1 Veneer ties around wall openings.Additional metal ties shall be provided around all wall openings greater than 16 inches (406 mm) in either dimension. Metal ties around the perimeter of openings shall be spaced not more than 3 feet (9144 mm) on center and placed within 12 inches (305 mm) of the wall opening. R703.7.4.2 Grout fill.
As an alternative to the air space required by Table R703.7.4, grout shall be permitted to fill the air space. When the air space is filled with grout, a water-resistive barrier is required over studs or sheathing. When filling the air space, replacing the sheathing and water-resistive barrier with a wire mesh and approved water-resistive barrier or an approved water-resistive barrier-backed reinforcement attached directly to the studs is permitted.
Approved corrosion-resistant flashing shall be applied shingle-fashion in a manner to prevent entry of water into the wall cavity or penetration of water to the building structural framing components. Self-adhered membranes used as flashing shall comply with AAMA 711. All exterior fenestration products shall be sealed at the juncture with the building wall with a sealant complying with AAMA 800 or ASTM C 920 Class 25 Grade NS or greater for proper joint expansion and contraction, ASTM C 1281, AAMA 812, or other approved standard as appropriate for the type of sealant. The flashing shall extend to the surface of the exterior wall finish. Approved corrosion-resistant flashings shall be installed at all of the following locations:
1. Exterior window and door openings. Flashing at exterior window and door openings shall extend to the surface of the exterior wall finish or to the water-resistive barrier for subsequent drainage. Flashing at exterior window and door openings shall be installed in accordance with one or more of the following:
1.1. The fenestration manufacturer’s installation and flashing instructions, or for applications not addressed in the fenestration manufacturer’s instructions, in accordance with the flashing manufacturer’s instructions. Where flashing instructions or details are not provided, pan flashing shall be installed at the sill of exterior window and door openings. Pan flashing shall be sealed or sloped in such a manner as to direct water to the surface of the exterior wall finish or to the water-resistive barrier for subsequent drainage. Openings using pan flashing shall also incorporate flashing or protection at the head and sides.
1.2. In accordance with the flashing design or method of a registered design professional.
1.3. In accordance with other approved methods.
1.4. In accordance with FMA/AAMA 100, FMA/AAMA 200, FMA/WDMA 250, or FMA/AAMA/WDMA 300.
2. At the intersection of chimneys or other masonry construction with frame or stucco walls, with projecting lips on both sides under stucco copings.
3. Under and at the ends of masonry, wood or metal copings and sills.
4. Continuously above all projecting wood trim.
5. Where exterior porches, decks or stairs attach to a wall or floor assembly of wood-frame construction.
6. At wall and roof intersections.
7. At built-in gutters.
EIFS with drainage shall comply with ASTM E 2568 and shall have an average minimum drainage efficiency of 90 percent when tested in accordance with ASTM E 2273.
R703.9.2.1 Water-resistive barrier.The water-resistive barrier shall comply with Section R703.2 or ASTM E 2570. R703.9.2.2 Installation.
The water-resistive barrier shall be applied between the EIFS and the wall sheathing.
All EIFS shall be installed in accordance with the manufacturer’s installation instructions and the requirements of this section.
R703.9.4.1 Terminations.The EIFS shall terminate not less than 6 inches (152 mm) above the finished ground level. R703.9.4.2 Decorative trim.
Decorative trim shall not be face nailed though the EIFS.
Vinyl siding, soffit and accessories shall be installed in accordance with the manufacturer’s installation instructions.
R703.11.1.1 Vinyl soffit panels.Soffit panels shall be individually fastened to a supporting component such as a nailing strip, fascia or subfascia component or as specified by the manufacturer’s instructions.
Vinyl siding used with foam plastic sheathing shall be installed in accordance with Section R703.11.2.2 or R703.11.2.3.
Reserved. R703.11.2.2 Design wind pressure rating.
The design wind pressure rating of the vinyl siding for installation over solid sheathing as provided in the vinyl siding manufacturer’s product specifications shall be adjusted for installation over foam plastic sheathing for the following wall assembly conditions:
1. Ultimate wind speeds, Vult, greater than 115 mph (51 m/s) and less than 130 mph (58 m/s):
a. For wall assemblies with foam plastic sheathing on the exterior side and gypsum wall board or equivalent on the interior side of the wall, the vinyl siding’s design wind pressure rating shall be multiplied by 0.39.
b. For wall assemblies with foam plastic sheathing on the exterior side and no gypsum wall board or equivalent on the interior side of wall, the vinyl siding’s design wind pressure rating shall be multiplied by 0.27.
The adjusted design pressure rating for the assembly shall meet or exceed the loads listed in Tables R301.2(2) adjusted for height and exposure using Table R301.2(3). Design pressures in Table R301.2(2) are permitted to be multiplied by 0.6.
2. Ultimate wind speeds, Vult, greater than 130 mph (58 m/s) and less than 140 mph (62.5 m/s):
a. The vinyl siding’s design wind pressure rating shall be multiplied by 0.27.
3. Ultimate wind speeds, Vult, equal to or greater than 140 mph (62.5 m/s):
Where the vinyl siding manufacturer’s product specifications provide an approved design wind pressure rating for installation over foam plastic sheathing, use of this design wind pressure rating shall be permitted and the siding shall be installed in accordance with the manufacturer’s installation instructions.
On exterior stud walls, adhered masonry veneer shall be installed:
1. Minimum of 4 inches (102 mm) above the earth;
2. Minimum of 2 inches (51 mm) above paved areas; or
3. Minimum of 1/2 inch (12 mm) above exterior walking surfaces which are supported by the same foundation that supports the exterior wall.