Which CONFAST anchor fits the job: concrete and drywall questions answered
Products in this guide
Which CONFAST anchor do I need?
- Load-bearing hold in dry concrete: the CONFAST Zinc-Plated Wedge Anchor for Concrete.
- Submerged or chemical-exposure concrete: CONFAST 316 Stainless Steel Concrete Wedge Anchor.
- Overhead pipe supports you unbolt later: the CONFAST Zinc Plated Drop-In Anchor.
- Removable block mount: the CONFAST Hex Head Concrete Screw (Box of 25).
- Wet or outdoor concrete and masonry: the CONFAST 304 Stainless Steel Hex Sleeve Anchor.
- Block in moist locations: the CONFAST Double Expansion Anchor.
- Conduit straps, set with a hammer: the CONFAST Hammer Drive Anchor (Box of 100).
- Drywall mounts: the CONFAST #8 Zinc Self-Drilling Drywall Anchor Kit w/Screws (Box of 100).
Pick the CONFAST anchor by what it goes into and whether the mount comes back off: the CONFAST Zinc-Plated Wedge Anchor for Concrete gives a load-bearing hold in dry concrete, and the CONFAST Zinc Plated Drop-In Anchor takes overhead supports you unbolt later.
On this page
- Concrete Anchors
- Why choose the CONFAST zinc plated drop-in anchor over a wedge anchor for hanging equipment from a concrete deck?
- What drill bit size do I need for a CONFAST zinc plated drop-in anchor?
- What size hole do I drill for a CONFAST 304 Stainless Steel Hex Sleeve Anchor?
- CONFAST 304 Stainless Steel Hex Sleeve Anchor or wedge anchor for concrete?
- Is the CONFAST zinc plated hex sleeve anchor OK outdoors or in a wet area?
- Why use a CONFAST machine screw anchor instead of a wedge anchor or a sleeve anchor?
- Should I use a CONFAST double expansion anchor or a single expansion anchor in block?
- What is a CONFAST hammer drive anchor, and when should I use one instead of a sleeve or wedge anchor?
- Which length CONFAST hammer drive anchor should I pick for attaching conduit strap to a concrete wall?
- Will CONFAST stainless drop-in anchors hold up outdoors or in a wet area?
- Can I use a CONFAST #8 zinc self-drilling drywall anchor in concrete or block?
- Concrete Screws
- Wedge Anchors
- Are CONFAST zinc-plated wedge anchors OK outdoors or in a wet environment?
- Are CONFAST wedge anchors made in the USA for a Buy American job?
- Are CONFAST galvanized wedge anchors OK for outdoor or wet locations?
- Is the CONFAST 316 stainless wedge anchor worth it over 304 or galvanized for coastal and wastewater anchoring?
- What size drill bit do I need for CONFAST galvanized wedge anchors?
- How tight should I torque a CONFAST galvanized wedge anchor?
- How do I pick the right CONFAST 304 Stainless Steel Concrete Wedge Anchor length for the thickness of what I'm bolting down?
Why choose the CONFAST zinc plated drop-in anchor over a wedge anchor for hanging equipment from a concrete deck?
Because the CONFAST Zinc Plated Drop-In Anchor sets flush with the concrete and is threaded inside, so the bolt or threaded rod can come out and go back in later.
- That makes it the usual pick for overhead pipe and duct supports and machinery bases that get serviced.
- It is rated for dry concrete only, so for block or a moist location use the CONFAST Machine Screw Anchor.
What drill bit size do I need for a CONFAST zinc plated drop-in anchor?
Drill larger than the bolt: the CONFAST Zinc Plated Drop-In Anchor in 1/4 inch uses a 3/8 inch bit, 3/8 inch uses 1/2 inch, and 1/2 inch uses 5/8 inch.
- The hole takes the anchor body, not the bolt, which is why the bit runs bigger.
- Use a carbide hammer-drill bit and drill at least as deep as the minimum embedment.
- Minimum embedment is 1 inch on the 1/4 inch anchor and 2 inches on the 1/2 inch.
| CONFAST Zinc Plated Drop-In Anchor | |
|---|---|
| Anchor Size Option | 1/4" (Box of 100), 3/8" (Box of 100), 1/2" (Box of 50) |
What size hole do I drill for a CONFAST 304 Stainless Steel Hex Sleeve Anchor?
Drill the same size as the anchor: a 1/2 inch CONFAST 304 Stainless Steel Hex Sleeve Anchor goes into a 1/2 inch carbide-drilled hole in concrete, block or brick.
- Blow the hole clean.
- Drive the anchor through the fixture and tighten the hex nut to expand the sleeve.
| CONFAST 304 Stainless Steel Hex Sleeve Anchor | |
|---|---|
| Anchor Size Option | 1/4" x 1-3/8" (Box of 100), 5/16" x 2-1/2" (Box of 100), 3/8" x 1-7/8" (Box of 50), 3/8" x 3" (Box of 50), 3/8" x 4" (Box of 25), 1/2" x 2-1/4" (Box of 25) and 11 more |
CONFAST 304 Stainless Steel Hex Sleeve Anchor or wedge anchor for concrete?
Use the CONFAST 304 Stainless Steel Hex Sleeve Anchor where the base can be block, brick or concrete: it works in all three.
- The CONFAST 304 Stainless Steel Concrete Wedge Anchor is rated for concrete only, so it belongs in solid concrete.
- The sleeve anchor ships complete with sleeve, expander, washer and hex nut, all in 304 stainless.
Is the CONFAST zinc plated hex sleeve anchor OK outdoors or in a wet area?
No: the CONFAST Zinc Plated Hex Sleeve Anchor is rated for dry locations, so for wet or exterior work use the CONFAST 304 Stainless Steel Hex Sleeve Anchor, rated for wet locations.
- The zinc plated sleeve anchor is the standard choice for dry interior slabs and equipment bases.
- The 304 stainless sleeve anchor fits exterior work, parking structures, pool decks and rooftop equipment.
- The zinc plated one is concrete only, and the 304 Stainless Steel one also works in block and brick.
Why use a CONFAST machine screw anchor instead of a wedge anchor or a sleeve anchor?
Because the CONFAST Machine Screw Anchor is female, threaded on the inside: it sets flush and the bolt goes in afterward, so a fixture can come off and go back on without disturbing the anchor.
- That makes it the usual pick for overhead pipe hangers and electrical and mechanical equipment mounts.
- It is rated for block and for moist locations.
- Each size is expanded with the matching CONFAST Machine Screw Anchor Set Tool, sold separately.
| CONFAST Machine Screw Anchor | |
|---|---|
| Anchor Size Option | #10-24 (Box of 100), 1/2" (Box of 20), 1/4" (Box of 100), 3/8" (Box of 50), 5/16" (Box of 100), 5/8" (Box of 10) |
Should I use a CONFAST double expansion anchor or a single expansion anchor in block?
In block, use the CONFAST Double Expansion Anchor: it expands along its full length from both ends, where a single expansion anchor grips a short section and can spin in the hole.
- In sound concrete, the CONFAST Single Expansion Anchor, made for solid concrete, is usually enough.
- With either one, the bolt backs out and the fixture re-bolts to the same anchor.
- The CONFAST Double Expansion Anchor is rated for moist locations, such as mechanical rooms and parking structures.
What is a CONFAST hammer drive anchor, and when should I use one instead of a sleeve or wedge anchor?
The CONFAST Hammer Drive Anchor (Box of 100) is a one-piece body with a pin you drive with a hammer to expand it, with no wrench or torque setting.
- It is the fast choice for conduit straps and nameplates you do not plan to remove.
- It is rated for dry locations, and in hollow block it goes in the solid web, not the void.
- If the fixture has to come back off, use the CONFAST Machine Screw Anchor, which also works in block.
Which length CONFAST hammer drive anchor should I pick for attaching conduit strap to a concrete wall?
For a one-hole conduit strap, the 1/4" x 1" or 1/4" x 1-1/4" size of the CONFAST Hammer Drive Anchor (Box of 100) is usually the working size.
- Go to 1/4" x 2", 2-1/2", or 3" when fastening through furring, plywood or a thicker bracket.
- The 3/16" x 7/8" is the smallest of the eight and suits light signage and low-profile clips.
| CONFAST Hammer Drive Anchor (Box of 100) | |
|---|---|
| Anchor Size Option | 3/16" x 7/8", 1/4" x 3/4", 1/4" x 1", 1/4" x 1-1/4", 1/4" x 1-1/2", 1/4" x 2" and 2 more |
Will CONFAST stainless drop-in anchors hold up outdoors or in a wet area?
Yes: the CONFAST 304 Stainless Steel Drop-In Anchor is built entirely from 304 stainless steel and carries a wet location rating, so it works in exterior slabs, wash-down areas, mechanical rooms and pool decks.
- The CONFAST Zinc Plated Drop-In Anchor is rated for dry locations only.
- For submerged or chemical exposure, the CONFAST 316 Stainless Steel Drop-In Anchor carries that rating.
| CONFAST 304 Stainless Steel Drop-In Anchor | |
|---|---|
| Anchor Size Option | 1/4" (Box of 100), 3/8" (Box of 50), 1/2" (Box of 50), 5/8" (Box of 25), 3/4" (Box of 25) |
Can I use a CONFAST #8 zinc self-drilling drywall anchor in concrete or block?
No: the CONFAST #8 Zinc Self-Drilling Drywall Anchor Kit w/Screws (Box of 100) is made for standard gypsum board, so for concrete or block use the CONFAST Hex Head Concrete Screw (Box of 25).
- Its threads cut into the paper and gypsum core and will not bite in concrete, brick or block.
- It is self-drilling, so it needs no pilot hole, and it is made in the US.
- Each anchor comes with its matching screw.
Do I need an anchor or shield with a CONFAST hex head concrete screw?
No: the CONFAST Hex Head Concrete Screw (Box of 25) cuts its own threads in a pre-drilled hole, so no sleeve, shield or plug is needed.
- That makes it a removable fixing that also works in block walls.
- It is sized for concrete, block and other masonry, and rated for dry locations.
- For damp work, use the CONFAST Stainless Steel Hex Head Concrete Screw with Drill Bit (Box of 50).
| CONFAST Hex Head Concrete Screw (Box of 25) | |
|---|---|
| Screw Size Option | 3/8" x 1-3/4", 3/8" x 2-1/2", 3/8" x 3", 3/8" x 4", 3/8" x 5", 1/2" x 3" and 1 more |
Are CONFAST stainless hex head concrete screws OK outdoors or in a damp mechanical room?
Yes: the CONFAST Stainless Steel Hex Head Concrete Screw with Drill Bit (Box of 50) is 410 stainless steel and rated for moist locations, so it works in wash-down areas, damp basements, parking structures and exterior mounts.
- It is rated for concrete, block and brick.
- The matching drill bit ships in the box.
What size drill bit do I need for CONFAST stainless hex head concrete screws?
The bit ships in the box: the 1/4 inch CONFAST Stainless Steel Hex Head Concrete Screw with Drill Bit (Box of 50) uses a 3/16 inch carbide bit.
- The 3/16 inch screws use a 5/32 inch bit.
- Drill at least 1/4 inch deeper than the screw will embed, so cuttings have somewhere to go.
- The fixture hole for the 1/4 inch screw is 5/16 inch.
| CONFAST Stainless Steel Hex Head Concrete Screw with Drill Bit (Box of 50) | |
|---|---|
| Screw Size Option | 3/16" x 1-1/4", 3/16" x 1-3/4", 1/4" x 1-1/4", 1/4" x 1-3/4", 1/4" x 2-1/4", 1/4" x 2-3/4" and 1 more |
Are CONFAST zinc-plated wedge anchors OK outdoors or in a wet environment?
No: the CONFAST Zinc-Plated Wedge Anchor for Concrete is rated for dry locations, so for wet or outdoor slabs use the CONFAST 304 Stainless Steel Concrete Wedge Anchor, which is rated for wet locations.
- The 304 stainless wedge anchor works on exterior slabs, wash-down areas and damp interiors.
- Both are concrete only, so for block or brick use the CONFAST 304 Stainless Steel Hex Sleeve Anchor.
Are CONFAST wedge anchors made in the USA for a Buy American job?
Yes: the CONFAST Zinc-Plated Wedge Anchor for Concrete is made in the US, and so is the CONFAST Galvanized Wedge Anchor, Concrete Fastener.
- The CONFAST 304 Stainless Steel Concrete Wedge Anchor, rated for wet locations, is also made in the US.
- So is the CONFAST 316 Stainless Steel Concrete Wedge Anchor, rated for submerged and chemical exposure.
- For a federally funded job, your submittal still needs the manufacturer's own documentation.
Are CONFAST galvanized wedge anchors OK for outdoor or wet locations?
The CONFAST Galvanized Wedge Anchor, Concrete Fastener is rated for damp locations, which covers exteriors under cover, loading docks, parking structures and mechanical rooms.
- It is rated for solid concrete only, not block, brick or mortar joints.
- For continuous submersion or coastal salt spray, use the CONFAST 316 Stainless Steel Concrete Wedge Anchor instead.
- For wet locations, use the CONFAST 304 Stainless Steel Concrete Wedge Anchor, rated for wet locations.
Is the CONFAST 316 stainless wedge anchor worth it over 304 or galvanized for coastal and wastewater anchoring?
Yes, where salt or chemicals reach the anchor: the CONFAST 316 Stainless Steel Concrete Wedge Anchor is rated for submerged and chemical exposure locations, and its 316 stainless resists pitting and chloride attack.
- It is for salt spray on a pier, a chemical plant slab or a wastewater clarifier deck.
- It is made in the US and rated for solid concrete only.
- The 304 stainless steel wedge anchor is rated for wet locations, and the galvanized wedge anchor for damp locations.
| CONFAST 316 Stainless Steel Concrete Wedge Anchor | |
|---|---|
| Anchor Size Option | 1/4" x 3-1/4" (Box of 100), 5/8" x 5" (Box of 20) |
What size drill bit do I need for CONFAST galvanized wedge anchors?
Drill a 3/8 inch hole for the 3/8 inch CONFAST Galvanized Wedge Anchor, Concrete Fastener, because the bit matches the anchor diameter.
- Set through a fixture already in place, a 3/8 inch anchor needs a 1/2 inch fixture hole.
- Minimum embedment for the 3/8 inch anchor is 1-1/2 inches.
| CONFAST Galvanized Wedge Anchor, Concrete Fastener | |
|---|---|
| Anchor Size Option | 3/8" x 5" (Box of 50) |
How tight should I torque a CONFAST galvanized wedge anchor?
Torque the 3/8 inch CONFAST Galvanized Wedge Anchor, Concrete Fastener to 25 to 30 ft-lbs, its maximum installation torque.
- Use a torque wrench rather than an impact gun.
- Over-torquing pulls the stud through the expansion clip and the anchor stops holding.
- The nut on the 3/8 inch anchor takes a 9/16 inch wrench or socket.
How do I pick the right CONFAST 304 Stainless Steel Concrete Wedge Anchor length for the thickness of what I'm bolting down?
Work from the maximum fixture thickness, not the overall length: the 1/2 inch x 5-1/2 inch CONFAST 304 Stainless Steel Concrete Wedge Anchor, rated for wet locations, clamps up to 2-3/4 inches of fixture.
- The 1/2 inch x 2-3/4 inch CONFAST Zinc-Plated Wedge Anchor for Concrete, rated for dry locations, clamps only 1/8 inch.
- Add plate thickness to 2-1/4 inches of embedment: the 1/2 inch x 5-1/2 inch clamps up to 2-3/4 inches.
| CONFAST 304 Stainless Steel Concrete Wedge Anchor | |
|---|---|
| Anchor Size Option | 1/2" x 5-1/2" (Box of 25), 3/4" x 5-1/2" (Box of 20) |