# Wood and Steel Framing

## Wood Framing Basics

### Lumber Sizes (Actual)
| Nominal | Actual |
|---------|--------|
| 2×4 | 1-1/2" × 3-1/2" |
| 2×6 | 1-1/2" × 5-1/2" |
| 2×8 | 1-1/2" × 7-1/4" |
| 2×10 | 1-1/2" × 9-1/4" |
| 2×12 | 1-1/2" × 11-1/4" |
| 4×4 | 3-1/2" × 3-1/2" |
| 6×6 | 5-1/2" × 5-1/2" |

### Lumber Grades
| Grade | Use |
|-------|-----|
| Select Structural | Highest strength |
| No. 1 | Heavy loads, long spans |
| No. 2 | General framing |
| No. 3 | Light framing, studs |
| Stud | Wall studs only |

### Moisture Content
| Category | MC | Use |
|----------|-----|-----|
| S-DRY | ≤19% | Standard framing |
| MC-15 | ≤15% | Interior trim |
| KD | Kiln-dried | Premium |

---

## Wall Framing

### Stud Spacing
| Loading | Spacing | Notes |
|---------|---------|-------|
| Bearing wall | 16" O.C. | Standard |
| Non-bearing | 24" O.C. | Allowed |
| High wind | 16" O.C. | May require 12" |

### Header Sizing
| Opening | Header (1-story) | Header (2-story) |
|---------|------------------|------------------|
| 3'-0" | 2-2×6 | 2-2×8 |
| 4'-0" | 2-2×6 | 2-2×10 |
| 6'-0" | 2-2×8 | 2-2×12 |
| 8'-0" | 2-2×10 | 2-2×12 or LVL |
| 10'-0" | 2-2×12 | LVL/PSL |
| 12'+  | LVL/PSL | Steel or LVL |

### Wall Components
| Component | Description |
|-----------|-------------|
| Sole plate | Bottom plate, on subfloor |
| Top plate | Single at top of studs |
| Double top plate | Required for bearing walls |
| King stud | Full stud at opening |
| Jack stud (trimmer) | Supports header |
| Cripple stud | Short stud above/below opening |
| Fire blocking | Required at 10' max |

---

## Floor Framing

### Joist Sizing (40 psf LL, No. 2 SPF)
| Span | 16" O.C. | 24" O.C. |
|------|----------|----------|
| 10' | 2×8 | 2×10 |
| 12' | 2×10 | 2×12 |
| 14' | 2×10 | 2×12 |
| 16' | 2×12 | I-joist |
| 18'+ | I-joist | I-joist |

### Engineered Floor Systems
| Product | Span Capability | Depth |
|---------|-----------------|-------|
| I-joist | 24'-32' | 9-1/2" to 16" |
| LVL | 20'-28' | 9-1/2" to 18" |
| Floor truss | 30'-40' | 12" to 24" |

### Blocking Requirements
- At bearing walls
- At 8' O.C. for dimension lumber
- At rim joist
- Under parallel partitions

---

## Roof Framing

### Rafter Sizing (20 psf LL, No. 2 SPF)
| Span | 16" O.C. | 24" O.C. |
|------|----------|----------|
| 10' | 2×6 | 2×8 |
| 12' | 2×8 | 2×8 |
| 14' | 2×8 | 2×10 |
| 16' | 2×10 | 2×10 |
| 18' | 2×10 | 2×12 |
| 20'+ | 2×12 | LVL/Truss |

### Roof Truss Advantages
- Longer spans (40'+)
- Open attic space
- Faster installation
- Engineered design

### Ridge Requirements
| Roof Type | Ridge |
|-----------|-------|
| Stick framed | Ridge board (non-structural) |
| Cathedral/no ceiling tie | Ridge beam (structural) |
| Truss | None (self-supporting) |

---

## Sheathing

### Wall Sheathing
| Material | Thickness | R-Value | Structural |
|----------|-----------|---------|------------|
| Plywood (CDX) | 7/16"-1/2" | ~R-0.6 | Yes |
| OSB | 7/16"-1/2" | ~R-0.6 | Yes |
| Foam + OSB | 1/2" + R | R-3 to R-10 | Yes |
| Gypsum | 1/2"-5/8" | ~R-0.5 | Limited |

### Roof Sheathing
| Material | Thickness | Rafter Spacing |
|----------|-----------|----------------|
| Plywood | 15/32" | 24" O.C. |
| Plywood | 7/16" | 16" O.C. |
| OSB | 7/16" | 24" O.C. |
| OSB | 3/8" | 16" O.C. |

### Floor Sheathing
| Material | Thickness | Joist Spacing |
|----------|-----------|---------------|
| Plywood | 23/32" (3/4) | 24" O.C. |
| OSB | 23/32" (3/4) | 24" O.C. |
| Plywood | 19/32" (5/8) | 16" O.C. |

---

## Connections

### Nailing Schedule (Common)
| Connection | Nail Size | Quantity |
|------------|-----------|----------|
| Stud to plate | 16d | 2 end-nailed |
| Double plate | 16d | 16" O.C. |
| Joist to sill | 3-8d | 3 toenails |
| Rafter to plate | 3-16d | 2 end, 1 toe |
| Sheathing (walls) | 8d | 6"/12" |
| Sheathing (roof) | 8d | 6"/12" |
| Subfloor | 8d or screws | 6"/12" |

### Metal Connectors
| Connector | Use | Capacity |
|-----------|-----|----------|
| Joist hanger | Joist to beam | 500-5,000 lbs |
| Hurricane clip | Rafter to wall | 500-1,500 lbs |
| Post cap | Beam to post | 2,000-10,000 lbs |
| Post base | Post to concrete | 2,000-10,000 lbs |
| Hold-down | Shear wall | 3,000-15,000 lbs |
| Strap | Member to member | 500-3,000 lbs |

---

## Cold-Formed Steel Framing

### Member Sizes
| Designation | Depth | Flange | Thickness |
|-------------|-------|--------|-----------|
| 350S162-33 | 3-1/2" | 1-5/8" | 33 mil |
| 400S162-43 | 4" | 1-5/8" | 43 mil |
| 600S162-54 | 6" | 1-5/8" | 54 mil |
| 800S162-68 | 8" | 1-5/8" | 68 mil |

### Thickness (Gauge)
| Mil | Gauge | Thickness |
|-----|-------|-----------|
| 33 | 20 ga | 0.0346" |
| 43 | 18 ga | 0.0451" |
| 54 | 16 ga | 0.0566" |
| 68 | 14 ga | 0.0713" |
| 97 | 12 ga | 0.1017" |

### Applications
| Application | Typical Members |
|-------------|-----------------|
| Non-bearing walls | 33-43 mil studs |
| Bearing walls | 43-54 mil studs |
| Floor joists | 54-68 mil joists |
| Roof | 33-54 mil rafters |

---

## Structural Steel

### Common Shapes
| Shape | Use |
|-------|-----|
| W (wide flange) | Beams, columns |
| S (American standard) | Older construction |
| C (channel) | Framing, miscellaneous |
| L (angle) | Bracing, lintels |
| HSS (tube) | Columns, exposed |
| Pipe | Columns, rails |

### Beam Sizing (Rules of Thumb)
| Span | Depth |
|------|-------|
| 10' | W8 |
| 15' | W10 |
| 20' | W12 |
| 25' | W14 |
| 30' | W16 |
| 35' | W18 |
| 40' | W21 |

### Connection Types
| Type | Use |
|------|-----|
| Shear tab | Simple connection |
| Clip angle | Simple connection |
| End plate | Moment connection |
| Welded | Moment connection |
| Bolted | Field connection |

### Bolt Grades
| Grade | Strength | Use |
|-------|----------|-----|
| A307 | 60 ksi | Non-structural |
| A325 | 120 ksi | Structural |
| A490 | 150 ksi | High strength |

---

## Fire Protection

### Wood Fire-Blocking
| Location | Requirement |
|----------|-------------|
| Vertical | 10' max height |
| Horizontal | At floor/ceiling |
| Concealed spaces | Subdivide |
| Stair stringers | Block at top |
| Soffits | At exterior walls |

### Steel Fireproofing
| Method | Rating Available |
|--------|------------------|
| Spray-applied | 1-4 hours |
| Intumescent paint | 1-2 hours |
| Board systems | 1-4 hours |
| Concrete encasement | 2-4 hours |

### Type V Construction (Wood)
| Element | Requirement |
|---------|-------------|
| Exterior walls | 1-hour or less |
| Interior bearing | 1-hour or less |
| Floor | 1-hour or less |
| Roof | No requirement |
| Height limit | 60' |

---

## Hurricane/High Wind

### Florida Requirements
| Component | Requirement |
|-----------|-------------|
| Roof sheathing | 8d @ 6" edge, 6" field |
| Wall sheathing | 8d @ 4" edge, 6" field |
| Roof-to-wall | Hurricane clips every truss |
| Wall-to-floor | Straps at each level |
| Sill-to-foundation | Anchor bolts @ 4' O.C. |

### High-Wind Connectors
| Location | Connector |
|----------|-----------|
| Roof to wall | H2.5 or H10 |
| Wall to wall | MST or similar |
| Wall to foundation | MASA or HD |
| Continuous tie | Threaded rod |

---

## Engineered Wood

### LVL (Laminated Veneer Lumber)
| Use | Typical Sizes |
|-----|---------------|
| Headers | 1-3/4" × 9-1/2" to 18" |
| Beams | 3-1/2" × 9-1/2" to 24" |
| Rim board | 1-1/4" × 9-1/2" to 16" |

### Glulam
| Use | Typical Sizes |
|-----|---------------|
| Beams | 3-1/8" to 6-3/4" wide |
| Girders | 5-1/8" to 10-3/4" wide |
| Columns | 5-1/8" × 5-1/8" to 8-3/4" |

### PSL (Parallel Strand Lumber)
| Use | Notes |
|-----|-------|
| Headers | High strength |
| Columns | Point loads |
| Beams | Long spans |

### CLT (Cross-Laminated Timber)
| Use | Notes |
|-----|-------|
| Floors | Structural + finish |
| Walls | Structural + finish |
| Roofs | Exposed structure |
