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Full Specification

Type

Concrete Screw (Tapcon)

Diameter

1/4"

Available Lengths

1-3/4", 2-1/4", 2-3/4", 3-1/4", 4"

Pilot Hole Diameter

3/16"

Pilot Hole Depth

1-1/4" min

Embedment Depth

1" minimum, 1-3/4" maximum

Recommended Torque

Driven, not torqued

Compatible Substrates

Concrete, Brick, CMU block (solid face), Stone

Load Rating

188 lbs tension, 225 lbs shear safe working load — Ultimate: 750 lbs tension / 900 lbs shear — Ultimate values in 2000 PSI concrete (Confast). Allowable calculated at the industry-standard 4:1 safety factor. — Block is much weaker than concrete: 500 lbs ultimate (125 allowable) in medium-weight block, 250 (63 allowable) in light-weight block.

Material

Carbon steel (blue), Stainless steel (silver)

Removable

Yes

Best For

✓Lumber to concrete
✓Handrail brackets
✓Shelving brackets
✓Heavier fixtures

Not For

✗Hollow block
✗High seismic zones without engineer review
✗Overhead structural

How a Tapcon Grips

Tapcon-style concrete screws cut their own threads directly into the base material, which is why the pilot hole is smaller than the screw's nominal diameter: the threads need solid material to bite into. Drill the hole too large and the threads have nothing to grip; too small and the screw strips or snaps during driving.

Installation Tips

1.Use a 3/16" carbide masonry bit — smaller than the anchor diameter, so the threads can grip

2.Clean the hole with compressed air before driving

3.Apply steady torque — stop immediately if resistance drops (stripped thread)

4.For exterior use, specify stainless or hot-dip galvanized

5.Stainless Tapcons use the same 3/16" pilot as blue Climaseal — the 5/16" often quoted is the nut driver size, not the drill bit

Frequently Asked Questions

What size drill bit does a 1/4" Tapcon need?

Use a 3/16" carbide masonry bit, drilled to 1-1/4" min.

How much weight can a 1/4" Tapcon hold?

188 lbs tension, 225 lbs shear safe working load. Actual capacity depends on base material strength and embedment — verify against the manufacturer's ICC-ES ESR data for structural work.