# Florida Building Code - Plumbing Requirements

**Based on**: 7th Edition Florida Building Code - Plumbing (2023)
**Reference Standards**: International Plumbing Code (IPC), ASME, ASSE, NSF

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## Quick Reference - Critical Values

| Requirement | Value | Code Reference |
|-------------|-------|----------------|
| Water closet (floor outlet) | 12" from finished wall | FPC 405.3 |
| Lavatory supply height | 19" - 24" AFF | FPC 405.3 |
| Shower drain (min) | 2" | FPC 709.3 |
| Floor drain (min) | 2" | FPC 709.3 |
| Bathtub drain | 1-1/2" | FPC 709.3 |
| Lavatory drain | 1-1/4" | FPC 709.3 |
| Kitchen sink drain | 1-1/2" | FPC 709.3 |
| Water heater T&P drain | 3/4" min | FPC 504.6 |
| Cleanout spacing | 100' max | FPC 708.1 |
| Min vent size | 1-1/4" | FPC 906.1 |
| Trap arm max length | Per trap size | FPC Table 1002.2 |
| Trap seal depth | 2" - 4" | FPC 1002.4 |
| Water pipe min velocity | 2 fps | FPC 604.3 |
| Water pipe max velocity | 8 fps | FPC 604.3 |

---

## Fixture Requirements

### Minimum Plumbing Fixtures (FPC Table 403.1)

#### Assembly (A-1, A-2, A-3)
| Fixture | Male | Female |
|---------|------|--------|
| Water closets | 1 per 125 | 1 per 65 |
| Urinals | 0 (optional per code) | - |
| Lavatories | 1 per 200 | 1 per 200 |
| Drinking fountains | 1 per 500 | 1 per 500 |
| Service sink | 1 per floor | 1 per floor |

#### Business (B)
| Fixture | Male | Female |
|---------|------|--------|
| Water closets | 1 per 25 (1-50), 1 per 50 thereafter | 1 per 25 (1-50), 1 per 50 thereafter |
| Urinals | May substitute up to 50% WC | - |
| Lavatories | 1 per 40 | 1 per 40 |
| Drinking fountains | 1 per 100 | 1 per 100 |
| Service sink | 1 per floor | 1 per floor |

#### Educational (E)
| Fixture | Male | Female |
|---------|------|--------|
| Water closets | 1 per 50 | 1 per 50 |
| Urinals | May substitute up to 50% WC | - |
| Lavatories | 1 per 50 | 1 per 50 |
| Drinking fountains | 1 per 100 | 1 per 100 |
| Service sink | 1 per floor | 1 per floor |

#### Mercantile (M)
| Fixture | Male | Female |
|---------|------|--------|
| Water closets | 1 per 500 | 1 per 500 |
| Urinals | May substitute up to 50% WC | - |
| Lavatories | 1 per 750 | 1 per 750 |
| Drinking fountains | 1 per 1000 | 1 per 1000 |
| Service sink | 1 per floor | 1 per floor |

#### Residential (R-1 Hotels)
| Fixture | Per Unit |
|---------|----------|
| Water closet | 1 |
| Lavatory | 1 |
| Bathtub/shower | 1 |
| Kitchen sink | 1 (if cooking) |

#### Residential (R-2 Apartments)
| Fixture | Per Unit |
|---------|----------|
| Water closet | 1 |
| Lavatory | 1 |
| Bathtub/shower | 1 |
| Kitchen sink | 1 |
| Laundry | 1 per dwelling or common |

### Accessible Fixtures

#### Water Closets
- **Height**: 17" - 19" to top of seat
- **Centerline**: 16" - 18" from side wall
- **Clear floor space**: 60" × 59" (side transfer)
- **Grab bars**: 42" side, 36" rear

#### Lavatories
- **Rim height**: 34" max AFF
- **Knee clearance**: 27" high, 8" deep min
- **Clear floor space**: 30" × 48" forward approach
- **Insulation**: Required on hot/drain pipes

#### Drinking Fountains
- **High-low**: Two heights or bottle filler
- **Spout height (low)**: 36" max
- **Clear floor space**: 30" × 48" forward approach

---

## Drainage System (DWV)

### Fixture Units (FPC Table 709.1)

| Fixture | Drainage FU |
|---------|-------------|
| Bathtub/whirlpool | 2 |
| Bidet | 1 |
| Clothes washer (residential) | 2 |
| Clothes washer (commercial) | 3 |
| Dishwasher (residential) | 2 |
| Drinking fountain | 0.5 |
| Floor drain (2") | 2 |
| Floor drain (3") | 3 |
| Floor drain (4") | 4 |
| Kitchen sink (residential) | 2 |
| Kitchen sink (commercial) | 4 |
| Lavatory | 1 |
| Shower (residential) | 2 |
| Shower (gang/commercial) | 3 per head |
| Toilet (1.6 gpf) | 3 |
| Toilet (gravity tank) | 4 |
| Urinal (1 gpf) | 2 |
| Urinal (wall-hung) | 4 |
| Service sink/mop basin | 3 |

### Drain Pipe Sizing (FPC Table 710.1)

#### Horizontal Drainage Piping

| Pipe Size | Max Fixture Units | Slope |
|-----------|-------------------|-------|
| 1-1/4" | 1 | 1/4" per ft |
| 1-1/2" | 3 | 1/4" per ft |
| 2" | 6 | 1/4" per ft |
| 3" | 20 | 1/8" per ft |
| 4" | 160 | 1/8" per ft |
| 5" | 360 | 1/8" per ft |
| 6" | 620 | 1/8" per ft |
| 8" | 1400 | 1/8" per ft |

#### Building Drain/Sewer (1/8" slope)

| Pipe Size | Max Fixture Units |
|-----------|-------------------|
| 3" | 20 |
| 4" | 180 |
| 5" | 390 |
| 6" | 700 |
| 8" | 1600 |
| 10" | 2900 |
| 12" | 4600 |

### Minimum Drain Sizes (FPC 709.3)

| Fixture | Minimum Drain |
|---------|---------------|
| Bathtub | 1-1/2" |
| Bidet | 1-1/4" |
| Clothes washer standpipe | 2" |
| Dishwasher | 1-1/2" |
| Drinking fountain | 1-1/4" |
| Floor drain | 2" |
| Kitchen sink (residential) | 1-1/2" |
| Kitchen sink (commercial) | 2" |
| Lavatory | 1-1/4" |
| Shower (single stall) | 2" |
| Shower (gang) | 3" |
| Water closet | 3" (4" public) |
| Urinal (wall) | 2" |
| Urinal (stall) | 2" |

### Cleanouts (FPC 708)

#### Spacing
- **Horizontal drains**: Every 100' max
- **Change of direction**: At 45° or greater
- **Building drain/sewer**: At building line
- **Base of each stack**: Required

#### Size
- Cleanout = same size as pipe (up to 4")
- Pipes > 4": 4" cleanout minimum

#### Clearance
- **3" and smaller**: 12" in front
- **4" and larger**: 18" in front
- **Concealed cleanouts**: Accessible cover required

---

## Vent System

### Vent Sizing (FPC Chapter 9)

#### Individual Vents

| Drain Size | Min Vent Size | Max Developed Length |
|------------|---------------|---------------------|
| 1-1/4" | 1-1/4" | 30' |
| 1-1/2" | 1-1/4" | 30' |
| 2" | 1-1/2" | 30' |
| 3" | 2" | 30' |
| 4" | 3" | 30' |

#### Branch Vents

| FU Connected | Min Vent Size |
|--------------|---------------|
| 1-8 | 1-1/2" |
| 9-24 | 2" |
| 25-48 | 2-1/2" |
| 49-84 | 3" |
| 85-256 | 4" |

#### Vent Stack/Stack Vent

| Stack Size | FU Connected | Min Vent Size |
|------------|--------------|---------------|
| 2" | 12 | 1-1/2" |
| 3" | 30 | 2" |
| 4" | 100 | 3" |
| 5" | 200 | 3" |
| 6" | 500 | 4" |

### Trap Arm Limitations (FPC Table 1002.2)

| Trap Size | Max Trap Arm Length | Min Trap Arm Length |
|-----------|--------------------|--------------------|
| 1-1/4" | 2'-6" | 2× diameter |
| 1-1/2" | 3'-6" | 2× diameter |
| 2" | 5'-0" | 2× diameter |
| 3" | 6'-0" | 2× diameter |
| 4" | 10'-0" | 2× diameter |

### Vent Termination (FPC 903)
- **Height above roof**: 6" minimum (12" if snow)
- **Distance from vertical surface**: 10' min if wall extends 1' above vent
- **Distance from openable window**: 10' horizontal, 3' above
- **Distance from air intake**: 10' minimum

### Special Venting

#### Wet Venting (FPC 908)
- Bathroom group can wet vent through lavatory
- Horizontal wet vent: 2" minimum
- Max 2 fixtures per branch

#### Air Admittance Valves (FPC 917)
- **Prohibited**: Cannot be sole vent for building
- **Location**: 4" above horizontal drain
- **Access**: Required for inspection/replacement
- **Height**: 6" above flood level rim

---

## Water Supply System

### Water Pipe Sizing (FPC Chapter 6)

#### Minimum Sizes
| Fixture | Min Supply |
|---------|------------|
| Bathtub/shower | 1/2" |
| Bidet | 3/8" |
| Dishwasher | 1/2" |
| Drinking fountain | 3/8" |
| Hose bibb | 1/2" |
| Kitchen sink | 1/2" |
| Lavatory | 3/8" |
| Laundry | 1/2" |
| Water closet (tank) | 3/8" |
| Water closet (flush valve) | 1" |
| Urinal (flush valve) | 3/4" |

#### Minimum Pressure
- **At fixture**: 8 psi (residential), 15 psi (flush valves)
- **Water heater inlet**: 40-80 psi typical
- **PRV required**: When static > 80 psi

#### Minimum Flow Rates (FPC Table 604.3)

| Fixture | GPM |
|---------|-----|
| Bathtub | 4.0 |
| Bidet | 2.0 |
| Dishwasher | 2.75 |
| Kitchen sink | 2.5 |
| Lavatory | 0.5 |
| Shower | 2.0 |
| Water closet (tank) | 3.0 |
| Water closet (flush valve) | 25.0 |

### Water Fixture Units (FPC Table 604.5)

| Fixture | Cold | Hot | Total |
|---------|------|-----|-------|
| Bathtub | 1.4 | 1.4 | 2.0 |
| Dishwasher | - | 1.4 | 1.4 |
| Kitchen sink | 1.4 | 1.4 | 2.0 |
| Lavatory | 0.5 | 0.5 | 0.7 |
| Shower | 1.4 | 1.4 | 2.0 |
| Water closet (tank) | 2.2 | - | 2.2 |
| Water closet (flush valve) | 5.0 | - | 5.0 |
| Clothes washer | 1.4 | 1.4 | 2.0 |
| Hose bibb | 2.5 | - | 2.5 |

### Backflow Prevention (FPC 608)

#### Required Devices

| Application | Device |
|-------------|--------|
| **Irrigation systems** | Reduced pressure zone (RPZ) |
| **Fire sprinkler** | Double check valve assembly |
| **Boiler makeup** | RPZ |
| **Chemical dispensing** | Air gap or RPZ |
| **Hose bibb** | Vacuum breaker |
| **Submerged inlet** | Air gap |
| **Lab equipment** | RPZ or air gap |
| **Swimming pool fill** | Air gap or ASSE 1056 |

#### Air Gap Requirements
- **Min gap**: 2× pipe diameter
- **Never less than**: 1"
- **Measured from**: Flood level rim to outlet

#### Vacuum Breaker Heights
- **Atmospheric vacuum breaker**: 6" above flood level
- **Pressure vacuum breaker**: 12" above downstream use
- **Spill-resistant VB**: 6" above flood level

### Hot Water System

#### Temperature Requirements
| Application | Max Temp |
|-------------|----------|
| Showers/tubs (residential) | 120°F |
| Showers/tubs (public) | 120°F |
| Lavatory (public) | 110°F |
| General service | 120°F |
| Healthcare | 110°F point of use |

#### Mixing Valves (FPC 424)
- **Showers**: Anti-scald required (ASSE 1016)
- **Bathtubs**: Pressure-balanced or thermostatic
- **Public lavatories**: Point-of-use mixing valve

#### Water Heater Installation (FPC 504)
- **T&P relief valve**: Required, 3/4" min
- **Discharge**: To floor drain or exterior
- **Discharge termination**: 6" - 24" above floor/grade
- **Expansion tank**: Required for closed systems
- **Seismic strapping**: Required (per local jurisdiction)
- **Pan**: Required in locations where leakage causes damage
- **Pan drain**: 3/4" minimum

---

## Stormwater Drainage

### Roof Drainage (FPC Chapter 11)

#### Sizing Roof Drains

| Drain Size | Max Roof Area (sf) |
|------------|--------------------|
| 2" | 2,176 |
| 3" | 4,680 |
| 4" | 8,650 |
| 5" | 15,100 |
| 6" | 22,000 |
| 8" | 45,000 |

*Based on 4" per hour rainfall (Florida)*

#### Secondary Drainage
- **Required when**: Parapet height > 2" above roof
- **Method**: Scuppers, secondary drains, or overflow
- **Capacity**: 100% of primary system
- **Separate discharge**: To grade, not storm sewer

#### Scupper Sizing

| Scupper | Min Head | Max Flow |
|---------|----------|----------|
| 4" × 4" | 2" | 450 sf |
| 6" × 6" | 3" | 1,250 sf |
| 8" × 8" | 4" | 2,700 sf |

### Horizontal Storm Piping

| Pipe Size | Max Area (sf) at 1/8" slope |
|-----------|----------------------------|
| 3" | 2,176 |
| 4" | 4,680 |
| 5" | 8,650 |
| 6" | 15,100 |
| 8" | 35,000 |
| 10" | 65,000 |

---

## Florida-Specific Requirements

### Hurricane/Flood Zone

#### Equipment Above Flood Level
- **Water heaters**: Install above BFE
- **Water softeners**: Above BFE
- **Pressure tanks**: Above BFE or flood-resistant

#### Pipe Materials (Corrosion)
- **Coastal areas**: PVC, CPVC, or coated metal
- **Avoid**: Galvanized in salt air environments
- **Underground**: PVC, ductile iron, HDPE

### Pool/Spa Plumbing

#### Required Features
- **Main drain covers**: VGB Act compliant
- **Suction entrapment**: Dual drains or safety system
- **SVRS**: Safety vacuum release system if single drain
- **Backflow**: Required on fill line

#### Equipment Pad
- **Location**: Accessible for service
- **Clearance**: Per manufacturer
- **Drainage**: Proper slope away

### Reclaimed Water Systems

#### Cross-Connection Prevention
- **Color coding**: Purple pipe required
- **Labeling**: "RECLAIMED WATER - DO NOT DRINK"
- **Separate trenching**: From potable supply
- **No interior connections**: Exterior irrigation only

### Septic Systems (Florida)
- **Permit required**: Through DOH (Department of Health)
- **Setbacks**: Per county regulations
- **Soil testing**: Required
- **Tank sizing**: Based on bedrooms

---

## Materials & Installation

### Approved Pipe Materials

#### Water Supply
| Material | Above Ground | Underground |
|----------|--------------|-------------|
| Copper (Type K, L, M) | ✅ | ✅ (K, L only) |
| CPVC | ✅ | ✅ |
| PEX | ✅ | ✅ |
| PP (polypropylene) | ✅ | ❌ |
| Galvanized steel | ✅ | ❌ |
| Stainless steel | ✅ | ✅ |

#### Drainage/Vent
| Material | Above Ground | Underground |
|----------|--------------|-------------|
| ABS | ✅ | ✅ |
| Cast iron | ✅ | ✅ |
| PVC (DWV) | ✅ | ✅ |
| Copper DWV | ✅ | ✅ |
| Galvanized steel | ✅ | ❌ |

### Support Spacing

| Material | Horizontal | Vertical |
|----------|------------|----------|
| Copper (< 1-1/4") | 6' | 10' |
| Copper (> 1-1/4") | 10' | 10' |
| CPVC (< 1") | 3' | 10' |
| CPVC (> 1") | 4' | 10' |
| PEX | 32" | 10' |
| PVC (< 2") | 4' | 10' |
| PVC (> 2") | 4' | 10' |
| Cast iron | 5' | 15' |

### Protection Requirements

#### Penetrations
- **Fire-rated assembly**: Firestop required
- **Concealed spaces**: Metal protection plates
- **Thermal expansion**: Expansion loops or fittings

#### Insulation
- **Hot water (> 2")**: R-4 minimum
- **Hot water (< 2")**: R-3 minimum
- **Cold water in humid areas**: Vapor barrier
- **Exterior piping**: Freeze protection

---

## Quick Checklists

### Residential Rough-In
- [ ] Water heater T&P to exterior or drain
- [ ] Anti-scald valves at tub/shower
- [ ] Cleanout at building line
- [ ] Vent through roof (6" min above)
- [ ] AAV only as secondary venting
- [ ] Trap on every fixture
- [ ] Proper trap arm length
- [ ] Hose bibb with vacuum breaker

### Commercial Restroom
- [ ] Fixture count per occupancy
- [ ] Floor drain at water heater
- [ ] Floor drain at restroom (if required)
- [ ] Accessible fixtures (water closet, lavatory)
- [ ] Electric water cooler or bottle filler
- [ ] Mop/service sink
- [ ] Hot water at lavatories
- [ ] Sensor faucets (if specified)

### Kitchen (Commercial)
- [ ] Grease interceptor sized correctly
- [ ] Indirect waste from dishwasher
- [ ] Air gap at dishwasher
- [ ] Floor drains at proper locations
- [ ] Backflow on potable connections
- [ ] Hot water for 3-comp sink (140°F)
- [ ] Hand sink accessible

---

*Reference: Florida Building Code - Plumbing 7th Edition (2023)*
*Always verify with local AHJ for amendments and interpretations*
