Wood fasteners and metal connectors

One-line orientation

Fasteners and connectors are scored on holding power and corrosion fit — face vs end-grain nailing and hot-dipped-galvanized-with-treated-wood are the points the exam keeps returning to.

Key points

• Nail sizing: measured in penny (d) — small 2d up to large 60d; most common framing sizes run 6d–16d.
• Connection strength by direction:
  • Face nail — driven perpendicular to the surface; strongest.
  • Toe nail — driven at an angle; intermediate.
  • End nail (into end grain) — weakest.
• Nail coatings:
  • Bright — uncoated; interior only.
  • Hot-dipped galvanized — thick zinc coat; corrosion-resistant; exterior, moist, and treated-wood use.
  • Cold / electro-galvanized — thin zinc plate; limited moisture resistance, less durable than hot-dipped.
• Screws and lags:
  • Screws hold better than nails (threads → higher clamping force).
  • Wood screw — needs a pre-drilled pilot hole to avoid splitting.
  • Lag screw — large, heavy-duty, load-bearing; pilot hole + wrench to drive.
  • Bolts — carriage, machine, expansion, toggle, masonry anchor; pass through and clamp with a nut for the highest-load connections.
• Timber connectors: split-ring (metal ring set between two members to transfer load) and timber riveting (rivets through timber + steel plates).
• Sheet-metal connectors:
  • Joist hanger / beam hanger — support a member off a beam or ledger.
  • Post base — anchors a post to concrete/wood, lifts it clear of moisture.
  • Post cap — ties post top to the beam above.
  • Rafter / hurricane anchor (strap) — resists uplift at the roof-to-wall connection.
  • Gang-nail / truss (gusset) plate — toothed plate joining truss members.

Confusions / comparison

Nail connection	Direction	Holding power
Face nail	Perpendicular to surface	Strongest
Toe nail	At an angle	Intermediate
End nail	Into end grain	Weakest

Coating	Zinc	Use
Bright	None	Interior only
Hot-dipped galvanized	Thick	Exterior / moist / treated wood
Cold / electro-galvanized	Thin plate	Limited moisture resistance

Sheet-metal connector	What it joins	What it resists / its purpose
Joist / beam hanger	A member to a beam or ledger	Carries the member’s bearing load off the supporting beam
Post base	A post to concrete or wood below	Anchors the post and lifts its end clear of moisture
Post cap	A post top to the beam above	Ties the post head to the beam it supports
Rafter / hurricane anchor (strap)	Roof framing to the wall	Uplift at the roof-to-wall connection
Gang-nail / truss (gusset) plate	Truss members at a joint	Toothed plate locking truss members together

Fastener	Relative load capacity	Typical use
Nail (penny / d)	Lowest	General framing; 6d–16d most common
Wood screw	Higher than a nail (threaded grip)	Connections needing more clamping than a nail, pilot hole to avoid splitting
Lag screw	Heavy-duty, load-bearing	High-load joints; pilot hole, wrench-driven
Bolt	Highest	Passes through and clamps with a nut for the highest-load connections

Related

→ Wood treatment and preservatives (this topic): why treated wood forces hot-dip galvanized / stainless hardware · Wood framing systems (this topic): where hangers, post bases, and hurricane straps land in the assembly · Engineered wood products (this topic): connector demands at glulam and heavy-timber joints.