Common Fastener Types Reference
Why this matters
Wrong fastener = mount fails. Drywall anchor in concrete = comes loose. Concrete anchor in drywall = falls through. Wood screw in metal = stripped + spinning. Right fastener = solid mount for decades. Field techs install equipment + carry an assortment; the basics must be cold. This is the field card.
Wood screws
Standard wood screw: tapered shank, slot OR Phillips OR square drive head, 1/2" - 6" length. Sizes #6 - #14 (diameter).
Deck screw: corrosion-resistant coating (yellow zinc, black, ceramic), self-drilling Type 17 point, exterior use.
Construction screw (Spax, GRK, Power Pro): high-strength, often self-driving, replaces nail in many applications.
Drywall screw: bugle head, fine OR coarse thread (coarse for wood; fine for metal stud), 1-1/4" common.
Lag screw / lag bolt: large diameter (3/8", 1/2", 5/8"), hex head, structural connections.
Sheet metal screws
Self-tapping (TEK): drill point + thread; goes through sheet metal without pilot. #6 - #14.
Self-tapping pan head: cone-point; pilot hole required first.
Self-drilling: separate drill point + threads; for thicker metal.
Sheet metal screw for HVAC: #8 × 1/2" pan head Phillips; thousands per job.
Machine screws
Pan head, round head, flat head: matches countersink. #4 - #1/4" diameter.
Threads:
- Coarse (UNC): #6-32, #8-32, #10-24, 1/4-20
- Fine (UNF): #6-40, 1/4-28
Use: bolt-to-tapped-hole, machine fasteners, panel mounting.
Bolts + nuts
Hex bolt: hex head, machine thread. Strong; structural.
Carriage bolt: round head + square shank; turn-resistant in wood.
Stove bolt (slotted machine): older specification.
Nut types:
- Hex nut: standard
- Nylon-insert lock nut (Nyloc): vibration resistance
- Castle nut: cotter pin for safety
- Wing nut: hand-tightening
Washer types:
- Flat washer: distributes load
- Lock washer (split, star): friction-grip
- Fender washer: large OD; thin sheet metal
- Belleville (cup): spring tension
Concrete anchors
Plastic conical anchor: light duty 5 - 20 lb. #6 - #10 screw.
Lead expansion anchor (rawl plug): medium duty 20 - 60 lb. Older spec.
Plastic expansion anchor: better than conical; 20 - 80 lb.
Sleeve anchor (Power Bolt): steel sleeve expands as bolt tightens. 100 - 500 lb.
Wedge anchor: pre-drilled hole, hammer in, tighten nut expands wedge. 300 - 2,000 lb. Concrete fixture mounting.
Drop-in anchor: female anchor set with setting tool; bolt threads in afterward. Allows removal/reuse.
Epoxy anchor (HIT-HY, Powers C6): epoxy paste in drilled hole; threaded rod inserted. Highest strength + corrosion resistance. Heavy structural.
Toggle bolt (hollow wall): spring-toggle behind drywall; hollow doors + cabinet ends. 30 - 50 lb.
Drywall anchors
Self-drilling toggle (Wall-Dog, Cobra): drill + drive in one motion. Up to 50 lb shear.
Plastic toggle: anchor wings inside cavity. 25 - 50 lb.
Snaptoggle (TOGGLER): metal toggle on plastic strap. 250+ lb in 1/2" drywall.
Threaded drywall anchor (E-Z Ancor): thread directly into drywall. 25 - 75 lb depending on size.
Specialty fasteners
Tapcon (concrete screw): blue, hex head, drill 1/8" smaller pilot. 75 - 300 lb. Faster than expansion anchors.
Hilti X-DG (powder-actuated): shot into concrete with .22 charge. Steel framing to concrete. Specialty training required.
Powder-actuated framing pin: similar; framing to concrete.
Self-piercing screw (Tek): drills + threads into 22 - 12 gauge sheet metal.
Brass set screw: machine-tapped; locks pulley, gear, OR collar to shaft.
Cup hook: open hook; cabinet + closet hanging.
Eye hook: closed loop; hanging plants, chains.
Roofing fasteners
Roofing nail: galvanized, large head, ring-shank for asphalt shingles. 1-1/4" common.
Ridge cap nail: longer (1-1/2" - 2") for double thickness at ridge.
Coil nail (pneumatic): gun-fed for production work.
Tile screw / standing seam clip: specialty for metal roofing.
Strap, hanger, + hardware fasteners
Simpson Strong-Drive screw: structural fastener for joist hangers, holdowns, framing connectors. Specific length + diameter required by hanger spec.
Joist hanger nail: 10d × 1-1/2" common joist hanger nail; engineered for shear load.
Galvanized strap nail: hot-dip galvanized; exterior use.
Pneumatic + cordless gun nails
Finish nail: 15 - 16 ga; trim, crown molding.
Brad nail: 18 ga; light trim, picture frames.
Pin nail: 23 ga; delicate trim.
Framing nail: 8d, 10d, 12d, 16d; structural framing.
Roofing nail (coil): gun-fed.
Concrete pin: powder-actuated.
Material + corrosion considerations
Indoor dry: zinc-plated steel adequate.
Exterior + damp: galvanized (hot-dip preferred) OR ceramic coated.
Wet / submerged / marine: stainless steel (304 OR 316), silicon bronze.
ACQ-treated lumber: HDG OR stainless ONLY (regular zinc corrodes within 1 year).
Cedar / redwood: stainless OR aluminum for stain prevention.
Common fastener mistakes
Wrong anchor for substrate (light anchor in heavy load = falls). Skipping pilot hole on wood splits material. Over-torque on machine screw strips threads. Reusing damaged screw (rounded head = unable to remove later). Wrong drive (Phillips on square drive cams out). Galvanized fastener in ACQ lumber (corrodes; structural failure). Mixing metals (aluminum hanger + steel fastener = galvanic corrosion outdoor). Sheet metal screw in 1/8" steel (sheet metal screws max thin sheet; use machine screw + tapped hole). Skipping washer where required (point load distorts material).
Truck stock by trade
HVAC: sheet metal screws #8 × 1/2" (lots), self-tap #10 × 3/4", lag screws (mount equipment to studs), wedge anchors (concrete pad).
Plumbing: lag screws for bathtub support, stainless wood screws (deck-grade), threaded rod 1/2" + clamps, sleeve anchors.
Electrical: drywall anchors (multiple sizes), machine screws #8-32 + #10-32, switch + outlet mounting screws, ground screws (#10-32 green), conduit hangers.
Carpenter: deck screws, drywall screws (1-1/4 + 2"), construction screws (Spax), framing nails, joist hanger nails.
Torque guidelines
Wood screw in pine: 30 - 50 in-lb (snug, not stripped).
Sheet metal screw: 25 - 60 in-lb (firm; over-torque strips thin metal).
Lag screw 1/2": 50 - 100 ft-lb (heavy structural).
Machine bolt: per manufacturer spec; varies wildly with size + grade.
Electrical lugs: per circuit breaker / panel label (16 - 75 in-lb common).
The single most-useful fastener habit is the MATCH-FASTENER-TO-SUBSTRATE check before drilling. Look at what you're mounting to: drywall? cement board? concrete? steel stud? sheet metal? Wood stud? Each takes a different anchor. 5 seconds of identification + correct anchor selection = solid mount for 30 years. 5 seconds skipped + wrong anchor = comes loose in 30 days + return call. Carry the right 8 - 10 anchor types in the truck + you handle 95% of mounting work confidently.
References
- Manufacturer technical data (Simpson Strong-Tie, Hilti, Powers, ITW)
- ICC-ES ESR reports (anchor capacity ratings)
- ASTM A153 (zinc coating), ASTM B695 (mechanical galvanizing)
- AWS D1.1 (structural welding for non-fastener connections)
- Manuall internal: Fastener Torque Reference, Anchor Bolt Selection