Deletion legend:

[1- Default – Not related to structural wind resistance design]

[2- Fire/Life Safety]

[3- Covered in model base code]

[4- Code Cycle Modification to be submitted to strike section and refer to appropriate FBC,B sections]

SECTION R4413

[4- Code Cycle Modification to be submitted to strike section and refer to appropriate FBC,B and FBC,P sections]

HIGH-VELOCITY HURRICANE ZONES — STORM DRAINAGE

R4413.1 General.

R4413.1.1 Scope. The provisions of this section shall govern the materials, design, construction and installation of storm drainage.

R4413.1.2 Where required. All roofs, paved areas, yards, courts and courtyards shall drain into a separate storm sewer system, or a combined sewer system, or to an approved place of disposal. For one- and two-family dwellings, and where approved, storm water is permitted to discharge onto flat areas, such as streets or lawns, provided that the storm water flows away from the building.

R4413.1.3 Prohibited drainage. Storm water shall not be drained into sewers intended for sewage only.

R4413.1.4 Tests. The conductors and the building storm drain shall be tested in accordance with Section 312 of the Florida Building Code, Plumbing .

R4413.1.5 Continuous flow. The size of a drainage pipe shall not be reduced in the direction of flow.

R4413.1.6 Fittings and connections. All connections and changes in direction of the storm drainage system shall be made with approved drainage-type fittings in accordance with Table R4413.1.6 herein. The fittings shall not obstruct or retard flow in the system.

TABLE R4413.1.6

FITTINGS FOR CHANGE IN DIRECTION

TYPE OF FITTING PATTERN CHANGE IN DIRECTION

Horizontal to vertical Vertical to horizontal Horizontal to horizontal

Sixteenth bend X X X

Eighth bend X X X

Sixth bend X X X

Quarter bend X Xa Xa

Short sweep X Xa,b Xa,b

Long sweep X X X

Sanitary tee Xc

Wye X X X

Combination wye and eighth bend X X X

For SI: 1 inch = 25.4 mm.

a. The fittings shall only be permitted for a 2-inch or smaller fixture drain.

b. Three inches and larger.

c. For a limitation on double sanitary tees, see Section 706.3 of the Florida Building Code, Plumbing.

R4413.1.7 Roof design. Roofs shall be designed for the maximum possible depth of water that will pond thereon as determined by the relative levels of roof deck and overflow weirs, scuppers, edges or serviceable drains in combination with the deflected structural elements. In determining the maximum possible depth of water, all primary roof drainage means shall be assumed to be blocked.

R4413.1.8 Cleanouts required. Cleanouts shall be installed in the storm drainage system and shall comply with the provisions of this code for sanitary drainage pipe cleanouts.

SECTION R4413.2

HIGH VELOCITY HURRICANE ZONES — MATERIALS

R4413.2.1 General. The materials and methods utilized for the construction and installation of storm drainage systems shall comply with this section.

R4413.2.2 Inside storm drainage conductors. Inside storm drainage conductors installed above ground shall conform to one of the standards listed in Table R4413.2.2 herein.

TABLE R4413.2.2

ABOVE-GROUND DRAINAGE AND VENT PIPE

MATERIAL STANDARD

Acrylonitrile butadiene

styrene (ABS) plastic pipe ASTM D 2661; ASTM F 628; CSA B181.1

Brass pipe ASTM B 43

Cast-iron pipe ASTM A 74; CISPI 301;

ASTM A 888

Copper or copper-alloy pipe ASTM B 42; ASTM B 302

Copper or copper-alloy tubing (Type K, L, M or DWV) ASTM B 75; ASTM B 88;

ASTM B 251; ASTM B 306

Galvanized steel pipe ASTM A 53

Glass pipe ASTM C 1053

Polyolefin pipe CSA CAN/CSA-B181.3

Polyvinyl chloride (PVC) plastic pipe (Type DWV) ASTM D 2665; ASTM D 2949; ASTM F 891;

CSA CAN/CSA-B181.2

R4413.2.3 Underground building storm drain pipe. Underground building storm drain pipe shall conform to one of the standards listed in Table R4413.2.3 herein.

TABLE R4413.2.3

UNDERGROUND BUILDING DRAINAGE AND VENT PIPE

MATERIAL STANDARD

Acrylonitrile butadiene styrene (ABS) plastic pipe ASTM D 2661; ASTM F 628; CSA B181.1

Asbestos-cement pipe ASTM C 428

Cast-iron pipe ASTM A 74; CISPI 301;

ASTM A 888

Copper or copper-alloy tubing (Type K or L) ASTM B 75; ASTM B 88;

ASTM B 251

Polyolefin pipe CSA CAN/CSA-B181.3

Polyvinyl chloride (PVC) plastic pipe (Type DWV) ASTM D 2665; ASTM D 2949; ASTM F 891;

CSA CAN/CSA-B181.2

R4413.2.4 Building storm sewer pipe. Building storm sewer pipe shall conform to one of the standards listed in Table R4413.2.4.

R4413.2.5 Subsoil drain pipe. Subsoil drains shall be open-jointed, horizontally split or perforated pipe conforming to one of the standards listed in Table R4413.2.5.

R4413.2.6 Roof drains. Roof drains shall conform to ASME A112.21.2.

R4413.2.7 Fittings. Pipe fittings shall be approved for installation with the piping material installed, and shall conform to the respective pipe standards or one of the standards listed in Table R4413.2.7. The fittings shall not have ledges, shoulders or reductions capable of retarding or obstructing flow in the piping. Threaded drainage pipe fittings shall be of the recessed drainage type.

TABLE R4413.2.4

BUILDING STORM SEWER PIPE

MATERIAL STANDARD

Acrylonitrile butadiene styrene (ABS) plastic pipe ASTM D 2661; ASTM D 2751; ASTM F 628

Asbestos-cement pipe ASTM C 428

Cast-iron pipe ASTM A 74; CISPI 301;

ASTM A 888

Concrete pipe ASTM C 14; ASTM C 76;

CSA A257.1;

CSA CAN/CSA A257.2

Copper or copper-alloy tubing (Type K, L, M or DWV) ASTM B 75; ASTM B 88;

ASTM B 251; ASTM B 306

Polyvinyl chloride (PVC) plastic pipe (Type DWV, SDR26, SDR35, SDR41, PS50 or PS100) ASTM D 2665; ASTM D 2797; ASTM D 3034; ASTM F 891; CSA-B182.2;

CSA CAN/CSA-B182.4

Vitrified clay pipe ASTM C 4; ASTM C 700

TABLE R4413.2.5

SUBSOIL DRAIN PIPE

MATERIAL STANDARD

Asbestos-cement pipe ASTM C 508

Cast-iron pipe ASTM A 74; CISPI 301;

ASTM A 888

Polyethylene (PE) plastic pipe ASTM F 405

Polyvinyl chloride (PVC) plastic pipe (Type Sewer Pipe, PS25, PS50 or PS100) ASTM D 2729; ASTM F 891; CSA-B182.2;

CSA CAN/CSA-B182.4

Vitrified clay pipe ASTM C 4; ASTM C 700

TABLE R4413.2.7

PIPE FITTINGS

MATERIAL STANDARD

Acrylonitrile butadiene styrene (ABS) plastic pipe ASTM D 2468

Cast iron ASME B16.4; ASME B16.12; ASTM A 888

Chlorinated polyvinyl chloride (CPVC) plastic ASTM F 437; ASTM F 438; ASTM F 439

Copper or copper-alloy ASME B16.15; ASME B16.18; ASME B16.22; ASME B16.23; ASME B16.26; ASME B16.29; ASME B16.32

Gray iron and ductile iron AWWA C110

Malleable iron ASME B16.3

Plastic, general ASTM F 409

Polyethylene (PE) plastic ASTM D 2609

Polyvinyl chloride (PVC) plastic ASTM D 2464; ASTM D 2466; ASTM D 2467;

CSA CAN/CSA-B137.2

Steel ASME B16.9; ASME B16.11; ASME B16.28

SECTION R4413.3

RESERVED

SECTION R4413.4

HIGH-VELOCITY HURRICANE ZONES — CONDUCTORS AND CONNECTIONS

R4413.4.1 Prohibited use. Conductor pipes shall not be used as soil, waste or vent pipes, and soil, waste or vent pipes shall not be used as conductors.

R4413.4.2 Combining storm with sanitary drainage. The sanitary and storm drainage systems of a structure shall be entirely separate except where combined sewer systems are utilized. Where a combined sewer is utilized, the building storm drain shall be connected in the same horizontal plane through a single-wye fitting to the combined sewer at least 10 feet (3048 mm) downstream from any soil stack.

R4413.4.3 Floor drains. Floor drains shall not be connected to a storm drain.

SECTION R4413.5

HIGH-VELOCITY HURRICANE ZONES- ROOF DRAINS

R4413.5.1 Strainers. Roof drains shall have strainers extending not less than 4 inches (102 mm) above the surface of the roof immediately adjacent to the roof drain. Strainers shall have an available inlet area, above roof level, of not less than one and one-half times the area of the conductor or leader to which the drain is connected.

R4413.5.2 Flat decks. Roof drain strainers for use on sun decks, parking decks and similar areas that are normally serviced and maintained shall comply with Section R4413.5.1 or shall be of the flat-surface type, installed level with the deck, with an available inlet area not less than two times the area of the conductor or leader to which the drain is connected.

R4413.5.3 Roof drain flashings. The connection between roofs and roof drains which pass through the roof and into the interior of the building shall be made water tight by the use of approved flashing material.

SECTION R4413.6

HIGH VELOCITY HURRICANE ZONES- SIZE OF CONDUCTORS, LEADERS AND STORM DRAINS

R4413.6.1 General. The size of the vertical conductors and leaders, building storm drains, building storm sewers, and any horizontal branches of such drains or sewers shall be based on the 100-year hourly rainfall rate indicated in Figure R4413.6.1 or on other rainfall rates determined from approved local weather data.

R4413.6.2 Vertical conductors and leaders. Vertical conductors and leaders shall be sized for the maximum projected roof area, in accordance with Table R4413.6.2.

R4413.6.3 Building storm drains and sewers. The size of the building storm drain, building storm sewer and their horizontal branches having a slope of one-half unit or less vertical in 12 units horizontal (4-percent slope) shall be based on the maximum projected roof area in accordance with Table R4413.6.3. The minimum slope of horizontal branches shall be one-eighth unit vertical in 12 units horizontal (1-percent slope) unless otherwise approved.

R4413.6.4 Vertical walls. In sizing roof drains and storm drainage piping, one-half of the area of any vertical wall that diverts rainwater to the roof shall be added to the projected roof area for inclusion in calculating the required size of vertical conductors, leaders and horizontal storm drainage piping.

R4413.6.5 Parapet wall scupper location. Parapet wall roof drainage scupper and overflow scupper location shall comply with the requirements of the Florida Building Code, Residential .

R4413.6.6 Size of roof gutters. The size of semicircular gutters shall be based on the maximum projected roof area in accordance with Table R4413.6.6.

SECTION R4413.7

HIGH-VELOCITY HURRICANE ZONES- SECONDARY (EMERGENCY) ROOF DRAINS

R4413.7.1 Secondary drainage required. Secondary (emergency) roof drains or scuppers shall be provided where the roof perimeter construction extends above the roof in such a manner that water will be entrapped if the primary drains allow buildup for any reason.

R4413.7.2 Separate systems required. Secondary roof drain systems shall have piping the end point of discharge separate from the primary system. Discharge shall be above grade, in a location which would normally be observed by the building occupants or maintenance personnel.

FIGURE R4413.6.1

100-YEAR, 1-HOUR RAINFALL (inches)

EASTERN UNITED STATES

For SI: 1 inch = 25.4 mm.

Source: National Weather Service, National Oceanic and Atmospheric Administration, Washington, D.C.

TABLE R4413.6.2

SIZE OF VERTICAL CONDUCTORS AND LEADERS

DIAMETER OF LEADER (inches)a HORIZONTALLY PROJECTED ROOF AREA (square feet)

Rainfall Rate (inches per hour)

1 2 3 4 5 6 7 8 9 10 11 12

2 2,880 1,440 960 720 575 480 410 360 320 290 260 240

3 8,800 4,400 2,930 2,200 1,760 1,470 1,260 1,100 980 880 800 730

4 18,400 9,200 6,130 4,600 3,680 3,070 2,630 2,300 2,045 1,840 1,675 1,530

5 34,600 17,300 11,530 8,650 6,920 5,765 4,945 4,325 3,845 3,460 3,145 2,880

6 54,000 27,000 17,995 13,500 10,800 9,000 7,715 6,750 6,000 5,400 4,910 4,500

8 116,000 58,000 38,660 29,000 23,200 19,315 16,570 14,500 12,890 11,600 10,545 9,660

For SI: 1 inch = 25.4 mm,1 square foot = 0.0929 m2.

a. Sizes indicated are the diameter of circular piping. This table is applicable to piping of other shapes provided the cross-sectional shape fully encloses a circle of the diameter indicated in this table.

TABLE R4413.6.3

SIZE OF HORIZONTAL STORM DRAINAGE PIPING

SIZE OF HORIZONTAL PIPING (inches) HORIZONTALLY PROJECTED ROOF AREA (square feet)

Rainfall Rate (inches per hour)

1 2 3 4 5 6

1/8unit vertical in 12 units horizontal (1-percent slope)

3 3288 1644 1096 822 657 548

4 7520 3760 2506 1800 1504 1253

5 13360 6680 4453 3340 2672 2227

6 21400 10700 7133 5350 4280 3566

8 46000 23000 15330 11500 9200 7600

10 82800 41400 27600 20700 16580 13800

12 133200 66600 44400 33300 26650 22200

15 218000 109000 72800 59500 47600 39650

1/4unit vertical in 12 units horizontal (2-percent slope)

3 4640 2320 1546 1160 928 773

4 10600 5300 3533 2650 2120 1766

5 18800 9440 6293 4720 3776 3146

6 30200 15100 10066 7550 6040 5033

8 65200 32600 21733 16300 13040 10866

10 116800 58400 38950 29200 23350 19450

12 188000 94000 62600 47000 37600 31350

15 336000 168000 112000 84000 67250 56000

1/2unit vertical in 12 units horizontal (4-percent slope)

3 6576 3288 2295 1644 1310 1096

4 15040 7520 5010 3760 3010 2500

5 26720 13360 8900 6680 5320 4450

6 42800 21400 13700 10700 8580 7140

8 92000 46000 30650 23000 18400 15320

10 171600 85800 55200 41400 33150 27600

12 266400 133200 88800 66600 53200 44400

15 476000 238000 158800 119000 95300 79250

For SI: 1 inch = 25.4 mm, 1 square foot = 0.0929 m2.

TABLE R4416.6.6

SIZE OF SEMICIRCULAR ROOF GUTTERS

DIAMETER OF GUTTERS (inches) HORIZONTALLY PROJECTED ROOF AREA (square feet)

Rainfall rate (inches per hour)

1 2 3 4 5 6

1/16 unit vertical in 12 units horizontal (0.5-percent slope)

3 680 340 226 170 136 113

4 1440 720 480 360 288 240

5 2500 1250 834 625 500 416

6 3840 1920 1280 960 768 640

7 5520 2760 1840 1380 1100 918

8 7960 3980 2655 1990 1590 1325

10 14400 7200 4800 3600 2880 2400

1/8 unit vertical in 12 units horizontal (1-percent slope)

3 960 480 320 240 192 160

4 2040 1020 681 510 408 340

5 3520 1760 1172 880 704 587

6 5440 2720 1815 1360 1085 905

7 7800 3900 2600 1950 1560 1300

8 11200 5600 3740 2800 2240 1870

10 20400 10200 6800 5100 4080 3400

1/4 unit vertical in 12 units horizontal (2-percent slope)

3 1360 680 454 340 272 226

4 2880 1440 960 720 576 480

5 5000 2500 1668 1250 1000 834

6 7680 3840 2560 1920 1536 1280

7 11040 5520 3860 2760 2205 1840

8 15920 7960 5310 3980 3180 2655

10 28800 14400 9600 7200 5750 4800

1/2 unit vertical in 12 units horizontal (4-percent slope)

3 1920 960 640 480 384 320

4 4080 2040 1360 1020 816 680

5 7080 3540 2360 1770 1415 1180

6 11080 5540 3695 2770 2220 1850

7 15600 7800 5200 3900 3120 2600

8 22400 11200 7460 5600 4480 3730

10 40000 20000 13300 10000 8000 6660

For SI: 1 inch = 25.4 mm, 1 square foot = 0.0929 m2.

R4413.7.3 Sizing of secondary drains. Secondary (emergency) roof drain systems shall be sized in accordance with Section R4413.6 based on the rainfall rate for which the primary system is sized in Tables R4416.6.2, R4413.6.3 and R4413.6.6. Scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by Section R4413.1.7. Scuppers shall not have an opening dimension of less than 4 inches (102 mm). The flow through the primary system shall not be considered when sizing the secondary roof drain system.

TABLE R4413.7

SIZING SCUPPERS FOR A 5 INCHES PER HOUR RATE OF RAINFALL

HORIZONTALLY PROJECTED ROOF AREA (SQUARE FEET)

HEAD IN INCHES LENGTH OF WEIR IN INCHES

4 6 8 12 16 20 24

1 230 346 461 692 923 1153 1384

2 641 961 1282 1923 2564 3205 3846

3 1153 1730 2307 3461 4615 5769 6923

4 1794 2692 3589 5384 7179 8974 10769

For SI: 1 inch = 25.4 mm, 1 square foot = .0929 m2.

Note: to adjust this table for other than a 5-inch design rainfall rate multiply the square footage on the table by 5 then divide by the local design rainfall rate.

Example: For 4 inches of design rainfall rate a 4-inch long scupper with a 1-inch head would accommodate 287 square feet. 230 x 5.4 = 287.