🧰 Division 05 — Metals

Structural Steel • Cold-Formed Metal Framing • Joists/Decking • Misc. Metals (stairs/rails/ladders) • Fasteners • Coatings • QA/Inspection • Field Safety. Coordinate with AISC, AWS, RCSC, ASTM, IBC & your project specs.

🧭 Scope (What Div 05 Covers)

W-shapes, HSS, channels, angles, plates, embeds, base plates, anchor rods.
Open-web steel joists/joist girders; metal roof & floor decking; shear studs (if specified).
Cold-formed metal framing (studs, tracks, bridging, clips, deflection heads).
Misc. metals: stairs, railings/guardrails, ladders, bollards, lintels, supports, frames.
Shop priming/galvanizing, intumescent/Fire-Resistive (coord. with Div 07), touch-ups.

📚 Key References

AISC Code of Standard Practice; Steel Construction Manual.
AWS D1.1 Structural Welding (Steel); D1.3 (Sheet Steel).
RCSC Specification for Structural Joints Using High-Strength Bolts.
ASTM A36/A572/A992 materials; F3125 (A325/A490) bolts; A153/A123 galvanizing.
ICC-ES ESR for post-installed anchors (Hilti/Simpson), epoxy/expansion types.

🔩 Shapes & Materials (Quick)

W-Shapes (e.g., W12×26 → ~26 lb/ft)
HSS tubes (e.g., HSS6×4×3/8)
Channels (C8×11.5), Angles (L4×3×¼)
Plate: A36/A572; SS when specified
Bolts: F3125 Gr A325/A490
Anchor rods: F1554 (Gr 36/55/105)

🎨 Coatings & Finishes

Shop prime (SSPC-PA 1) unless fireproofed; field touch-up at burns/bolts.
Galvanize per A123 (members) / A153 (hardware); avoid unsealed overlaps.
Intumescent/FRM: verify thickness, compatible primers, environmental limits.
Stainless/Aluminum items: isolate from carbon steel to reduce galvanic corrosion.

🔧 High-Strength Bolting

Snug-Tight vs Pretensioned (turn-of-nut/DTI/tensioning) — slip-critical requires pretension.
Holes: standard, short-slot, long-slot (direction per drawings).
Install: hardened washers as required; do not reuse A490; match nut/bolt grades & coatings.
Verify faying surface class & cleanliness for slip-critical joints.

🧯 Welding Basics (AWS D1.1)

Follow WPS/PQR; qualified welders; correct process (SMAW/FCAW/GMAW).
Preheat/interpass per D1.1 & material thickness — keep records where required.
Back-gouge/backing, fillet sizes, continuity plates as detailed.
Field welds need access, weather protection, hot-work permits, fire watch.

🧱 Cold-Formed Metal Framing (CFMF)

Studs: 20–12 ga; common depths 3-5/8", 6", 8"; deflection criteria (L/240–L/360 typical).
Deflection heads: slotted track or slip clips — no fasteners through slip.
Bridging: cold-rolled channels + clips @ 4' o.c. (typ.) or per engineer; strap bracing at ends.
Exterior studs: sheath before cladding; corrosion-resistant screws/washers.

🪵 Metal Deck & Shear Studs

Roof deck: types B (wide rib) / N (deep) — typical 36" coverage.
Floor deck: 1.5"–3" composite; puddle welds or screws per pattern.
Side-lap stitching at each rib (typ.); closures at edges/openings.
Studs (if shown): size/spacing per engineer; weld through deck as permitted.

🪜 Joists & Girders (SJI)

Erect bridging as soon as practical; do not load until bridged & plumbed.
Seat connection bolts snug-tight min; add ties/bridging per joist tagging.
Check camber orientation; confirm bearing length and end conditions.

🧗 Stairs, Rails & Ladders

Guard height 42" (typ.); handrail 34–38" above nosings; 4" max sphere at guards (verify code).
Treads/riser uniformity; nosing type; landing sizes per code.
Grating/diamond plate thickness per span; slip-resistant surfaces in egress.
OSHA fixed ladders: cages withdrawn on new work; use fall arrest systems.

🧱 Embeds • Base Plates • Anchors

Set templates & verify bolt patterns; protect threads; check projection.
Grout base plates after plumbing; shim stacks kept compact; verify edge distances.
Post-installed anchors: follow ESR, hole cleaning, cure times, torque tests as required.

🧮 Quick Math & Takeoff Shortcuts

Steel Member Weight

Weight (lb) = (member lb/ft) × length (ft). Example: W12×26 @ 18' → 26×18 = 468 lb.

Plate/Bar Weight

lb/ft = 3.4 × t(in) × w(in); or lb = 40.8 × t(in) × area (sf).

Stud Count (CFMF)

Count ≈ (clear length ÷ spacing) + 1 (add jamb/kings/cripples per details).

Deck Sheets (36" Coverage)

Sheets across width ≈ width (ft) ÷ 3. Lengths are typically cut-to-run.

Base Plate Grout Volume

CF = (Plate A − Column A) × grout t(in)/12; CY = CF ÷ 27.

Anchor Rod Embed (ROTU)

Prelim only: ~12× rod Ø (designer governs; epoxy per ESR).

✅ QA / Special Inspection (IBC)

Shop drawings / connection design delegation noted clearly.
Material mill certs; bolt lot certs; weld filler classifications.
Bolting inspection: snug/pretension verification; DTI checks where used.
Weld inspection per AWS VT/MT/UT as specified; repair logs.
Deck fastener patterns; joist tags; bridging inspection.

📦 Submittals & Coordination

Stamps: approved/as-noted prior to fabrication. Confirm dimensions/tolerances.
RFI early on deflection heads, embeds, openings, sleeve locations, conflict zones.
Erection sequencing & crane picks; laydown & access routes.

🦺 Safety (Field)

Fall protection ≥6'; leading-edge work plans; controlled decking zones per OSHA.
Hot-work permits; fire watch; shield combustibles during cutting/welding.
Rigging inspections; taglines; suspended loads controls; exclusion zones.
Silica/metal fume exposure; ventilation/respiratory protection as required.

📝 Self Test

Which spec governs pretensioned bolt installation for slip-critical joints?
Give two differences between snug-tight and pretensioned bolted joints.
How many pounds does a ½" × 10" plate strip weigh per foot?
List two required items for post-installed epoxy anchors per ESR.
What is the typical coverage width of metal roof deck sheets?
How do you count studs for a 28' wall at 16" o.c. (clear length)?
Name two code checks for guardrails on steel stairs.
What document defines shop/field tolerances for structural steel?
Compute the weight of a W12×26 that is 24' long.
What does a deflection head detail prevent in CFMF walls?

Answers: (1) RCSC Specification. (2) Pretensioned requires calibrated tightening (e.g., turn-of-nut/DTI) and specified clamping force; snug-tight is wrench-snug only. (3) lb/ft = 3.4 × 0.5 × 10 = 17 lb/ft. (4) Hole cleaning/installation steps and cure times; proof/load tests if required. (5) ~36" typical. (6) (28'×12)/16 + 1 ≈ 21 + 1 = 22 studs (plus jambs as detailed). (7) Guard height 42" and 4" max sphere opening (verify local code). (8) AISC Code of Standard Practice. (9) 26 × 24 = 624 lb. (10) Transfers building deflection without crushing the wall/finish (slip).

Division 05