DIY Fasteners and Hardware: Screws, Bolts, Nails, and More
Fasteners are the unglamorous backbone of almost every DIY project — the things that hold the thing together. This page covers the major categories of mechanical fasteners used in home repair and improvement: screws, bolts, nails, anchors, and their supporting hardware. Choosing the wrong fastener is one of the most common causes of structural failure, so the distinctions between types matter more than most beginners expect.
Definition and scope
Walk into any hardware store and the fastener aisle will either reassure you or send you home without buying anything. There are over 200 distinct screw drive types catalogued by the Fastener Training Institute, and that's before counting nail gauges, bolt grades, or anchor systems. The scope of DIY fasteners covers any mechanical device that joins two or more materials — wood, metal, masonry, drywall, or composite — without relying primarily on adhesive.
That scope runs from a 1-inch drywall screw to a ½-inch Grade 8 hex bolt used in structural framing. It also includes the hardware that supports fasteners: washers, nuts, lock nuts, lag shields, and toggle bolts designed to bear load in hollow walls.
Fasteners are graded, sized, and specified by standards maintained by the American Society of Mechanical Engineers (ASME) and the Society of Automotive Engineers (SAE), along with metric equivalents governed by ISO standards. For structural applications in residential construction, the American Wood Council publishes the National Design Specification (NDS), which guides load-rated fastener selection in wood framing.
The materials landscape of fasteners is part of the broader DIY materials guide that covers substrate compatibility — because the fastener and the material it enters are a system, not two independent choices.
How it works
Every fastener holds by one of three mechanical principles: friction, tension, or bearing (shear resistance).
Nails hold primarily through friction and shear. A smooth shank nail grips by the compression of displaced fibers; a ring-shank or spiral-shank nail adds mechanical interlock that increases withdrawal resistance by as much as 40% over smooth shank, according to Forest Products Laboratory research.
Screws hold through thread engagement and tension. As the screw turns, the helical thread cuts or rolls into the substrate, and the clamping force between head and material is what does the real work. Thread pitch — the distance between threads — determines how much mechanical advantage the driver gains per revolution. A coarser thread (fewer threads per inch) drives faster in soft wood; a finer thread holds better in metal or hardwood.
Bolts are designed for through-fastening: they pass entirely through both materials and are secured by a nut on the opposite face. The clamping force is adjustable (by torque) and reversible — which makes bolts appropriate for assemblies that need to be disassembled and for structural connections where code may require specific load ratings.
Anchors solve a different problem: how to fasten into a material that has no useful grip on its own — hollow drywall, concrete, or brick. Toggle bolts spread load across a larger area inside a hollow cavity. Concrete wedge anchors expand against the sides of a drilled hole as the bolt is tightened.
Understanding these mechanisms is foundational to the broader skill set covered in DIY skills by difficulty level, which places fastener selection at the intermediate tier.
Common scenarios
- Hanging drywall — coarse-thread drywall screws, typically 1-5/8 inch for ½-inch drywall into wood studs. Fine-thread screws are used when attaching drywall to metal framing.
- Deck and outdoor framing — hot-dipped galvanized or ACQ-compatible structural screws and joist hanger nails. Standard zinc screws corrode rapidly in treated lumber; ACQ (alkaline copper quaternary) treated wood requires corrosion-resistant fasteners per ICC building code requirements.
- Cabinet installation — 3-inch cabinet screws into studs, plus ¼-20 bolts to join face frames of adjacent cabinets.
- Concrete and masonry — ½-inch concrete wedge anchors or Tapcon-style self-tapping masonry screws, requiring a hammer drill and a carbide-tipped bit sized to the anchor's specification.
- Hollow wall anchors — toggle bolts or snap toggles rated to specific load limits, typically printed on the packaging. The WingIts brand toggle, for example, rates to 265 pounds in ½-inch drywall for a single anchor.
Decision boundaries
The choice between fastener types is rarely aesthetic — it follows from four constraints: material, load direction, environment, and reversibility.
Material compatibility is the first gate. Driving a screw into concrete without pre-drilling doesn't work; it destroys the fastener. Nailing into hardwood without pre-drilling splits it. The material dictates the fastener class before anything else is considered.
Load direction separates nails from screws in many framing contexts. Nails resist shear (lateral load) better than withdrawal (pulling straight out). Screws are the reverse — far superior in withdrawal, adequate in shear. Joist hangers in residential framing use 10d (3-inch) nails specifically for their shear strength, not screws, regardless of what seems more convenient.
Environment governs corrosion class. Interior applications tolerate zinc-plated or uncoated steel. Exterior, pressure-treated lumber, and coastal environments require hot-dipped galvanized (HDG), stainless steel (Type 316 for marine), or specifically rated coated screws. Using an incompatible fastener in treated lumber can cause galvanic corrosion that visibly degrades the wood within 18 months.
Reversibility is often overlooked. Bolted connections can be taken apart cleanly. Screwed connections can be removed with effort. Nailed connections are functionally permanent — removal typically damages at least one of the joined materials.
For projects where permit requirements affect fastener specifications, the DIY permits and codes page covers jurisdiction-specific concerns. And for a broader grounding in the tools used to drive these fasteners — drills, impact drivers, nail guns — the DIY tools and equipment reference covers specs and selection in depth. The DIY home repair section applies these principles to the most common household repair scenarios. The full range of project types on doityourselfauthority.com is organized around this same foundation of material knowledge.