Concrete and Masonry Anchors

Builders Stainless stocks stainless steel concrete and masonry anchors in 303, 304, 316 and 410 grades: Titen HD® screw anchors, Strong-Bolt® 2 wedge anchors, concrete screws, drop-in anchors, sleeve anchors, Zinc Nailon™ drive pin anchors, and Simpson Strong-Tie® anchoring adhesives and epoxies. Brands stocked include Simpson Strong-Tie, DeWalt and Wej-it.

Grade matters more than size in coastal work. 316 stainless is the one to specify for salt water, salt air, pool decks and continuous dampness. 304 covers damp and general exterior work. 410 is a hardened grade used for concrete screws and is not a marine grade. Choose the anchor type by how it holds — screw, expansion or adhesive — and the grade by how wet and how salty the location is.

Simpson Strong-Tie Anchoring Adhesives & Epoxies

Choosing a concrete or masonry anchor

Anchors for concrete, brick and block hold in one of three ways: a screw that cuts its own threads, an expansion anchor that wedges against the sides of the hole, or an adhesive that bonds threaded rod into the hole. Which one you want depends on the load, whether the fixture ever has to come back off, and how much salt the connection sees.

Anchor type	How it holds	Comes back out?	Stainless grades stocked	Typical use
Titen HD® screw anchors	Cuts its own threads in the hole	Yes, and the hole is reusable	316	Structural connections, sill plates, heavy brackets
Concrete screws	Cuts its own threads in the hole	Yes	410 and 316	Light to medium fixtures, furring, conduit, trim
Strong-Bolt® 2 wedge anchors	Expansion clip wedges against the hole wall	No — permanent once set	304 and 316	Structural anchorage into cured concrete
Drop-in anchors	Internally threaded shell expanded with a setting tool	Bolt yes, shell no	303	Flush overhead and threaded-rod connections, dry interior
Sleeve anchors	Sleeve expands as the nut or screw draws the cone up	No	304	Brick, block and concrete, medium duty
Zinc Nailon™ drive pin anchors	Pin driven into a zinc alloy body	No	Zinc alloy body, 304 pin	Fast light fastening, furring strips, dry interior
Anchoring adhesives & epoxies	Bonds threaded rod or rebar into a cleaned hole	No	Use with 316 threaded rod	Close edge distances, rebar dowelling, cracked concrete

Which stainless grade do you need?

316 is the grade to specify anywhere salt is involved — oceanfront, docks, pool decks, bulkheads, and anything that stays damp. The added molybdenum is what resists chloride pitting, and it is the reason 316 costs more than 304. If the connection is structural and coastal, this is the one.

304 handles general exterior and damp work well away from salt spray. 410 is a hardened martensitic grade used for concrete screws because it has to be hard enough to cut threads in concrete; it is not a marine grade, and it will show surface rust in a coastal setting. 303 is a free-machining grade used for drop-in anchor bodies and belongs in dry interior work, not outdoors.

If you are weighing grades for a whole project, our guide to stainless steel grades for marine and coastal construction goes into the differences in more detail.

Common questions

Which anchor should I use on a dock or oceanfront project?

Specify 316 stainless. That means Titen HD® screw anchors, 316 wedge anchors, 316 concrete screws, or an adhesive anchor set with 316 threaded rod. Drop-in anchors, Zinc Nailon™ anchors and 410 concrete screws are not marine-grade and should stay inland and dry.

What is the difference between a screw anchor and a wedge anchor?

A screw anchor cuts its own threads into the hole and can be backed out, which makes it the choice when the fixture may come off again or when you need to work close to an edge. A wedge anchor expands against the hole wall and is permanent — it can be cut flush but not removed. Wedge anchors generally carry higher tension values in cured concrete.

Do I drill the hole the same size as the anchor?

It depends on the type. Concrete screws use a carbide bit smaller than the screw, because the threads have to cut into the concrete — and the right bit varies by brand even at the same nominal diameter. Expansion anchors such as wedge and sleeve anchors use a bit equal to the anchor diameter, since the anchor drops into the hole and then expands. Check the product page for the exact bit size before you drill.

Can I use these anchors in brick or block?

Some, not all. Concrete screws and sleeve anchors are rated for brick and grout-filled block as well as concrete. Wedge anchors and drop-in anchors are for cured concrete only. Adhesive anchors have separate hollow-base and grout-filled procedures. Base material approvals are listed on each product page.

Do these anchors carry code listings?

Several do. Titen HD® screw anchors are listed under ICC-ES ESR-1056 and IAPMO UES ER-493. Strong-Bolt® 2 wedge anchors are listed under ESR-3037 for concrete and IAPMO UES ER-240 for masonry. Concrete screws carry Florida Product Approval and Miami-Dade listings that vary by line. Check the individual product page for the listing that applies to your submittal.