When working on concrete construction projects, the choice of fastener is crucial to achieving a durable, long-lasting installation. Concrete nails, pins, and staples are designed specifically for anchoring materials like plywood, rebar, and paneling directly to hardened concrete. This article will explore some of the most commonly used concrete fastener types and best practices for selecting the right size.
Concrete Nail Sizes
Concrete nails are similar in shape to common steel nails but feature harder, high-carbon steel composition and barbed or threaded shanks for superior concrete embedment. Sizes range from small 2d-5d nails up to larger 8d-16d heavy duty nails. Larger nail diameters and thread densities provide maximum holding power:
- 2d-4d nails: Used for light duty like wood stripping or baseboards. Offer lower load capacity.
- 6d nails: General purpose nail for many wood applications including formwork bracing.
- 8d nails: Good balance of strength and ease of driving. Common for plywood roof/floor sheathing.
- 10d-16d nails: Heavy duty nails ideal for scaffold planks, dimensional lumber or when wind/seismic loads are high. Harder to drive without powder-actuated tools.
Nails longer than 2.5″ usually require predrilling to avoid concrete cracking during installation. To estimate proper fastener spacing, multiply nail diameter by 16 and space on that center-to-center basis. Stagger nails in wood members for stronger anchorage.
Concrete Anchor/Drive Pins
Also called stud pins or concrete nail pin, these fat, blunt-ended pins feature round shafts like nails but larger diameters of 1/4”-3/4”. Designed to provide high pull-out and shear values when driven full depth into uncured or hardened concrete. Common uses include:
- -Tying rebar and mesh together during concrete pours.
- -Anchoring base plates, light fixtures, edge rails, signs and more.
- -Fastening wood blocking or backing directly into interior/exterior walls.
Pins install easily with a hammer and offer load capacity often exceeding bolts or liquid anchors. For hardened concrete, predrilling the same diameter as the pin shaft allows full embedment.
Staples for Concrete
Powder-actuated concrete staples, sometimes called powder or 14 series staples, resemble distorted staple gun staples. Made from hardened steel, these drive effortlessly into cured concrete using specially-designed powder guns. Common sizes include No.8, No.10 and No.12 weighing 3/4oz-1oz each.
They anchor thin, flexible materials adeptly such as wire mesh, thin plastic sheets, vapor barriers, insulation board and polyethylene sheeting. Staples do not rust like nails and provide corrosion-resistant holding. Spacing is 6”-12” depending on material thickness and strength requirements.
Precautions for Concrete Fastening
Drill holes same diameter as pins/nails to prevent cracking concrete. Use hammer drill for harder concrete.