What are Lag Shield Concrete Anchors? | Fasteners 101

What are Lag shields? What are expansion shield anchors? How do they work? These concrete, brick, and block anchors raise many questions, especially since they look different from most typical anchors.

Let us help you answer some of these questions so you can determine if lag shields, otherwise known as expansion shield anchors, are right for your project.

[agentmango]

A note about lag shields, make sure to use the same brand lag bolt and lag shield. Mixing brands might lead to a mismatch in thread pitch, which is sub-optimal for how lag shields work. (Apologies if you've already mentioned this in the video, I forget!)

A pro or con to lag shields is how wide they are. For example, a 1/4" lag bolt can work with either a 5/16" DuoPower anchor or a 1/2" wide lag shield. When I recently redid the fasteners holding the steel railing to my stone porch I ended up using a mix of both. For the holes where the old #14 screw came out cleanly, I hammer drilled to 5/16" and used the plastic anchor. For the holes where the #14 screw was rusted through and thus half remained inside, (EZ-outs failed, so) the only way I could get it out was with a 1/2" diamond hole saw; for those holes I used a lag shield.

[gatorwing]

Always blow out the concrete dust out of the drilled hole in the concrete before inserting the anchor or sacrifice some holding power. A simple rubber ball hand blower works great.

[Drew]

Are these leg shields removable? I know the bull is obviously but is the shield itself also removable or will that shield stay in the concrete forever if the lag bolt is removed? Thanks

[frostydmbk]

Hi, would these work for installing a pull up bar into a concrete wall? If not could you recommend your best suggestion please??

[chrispowers]

great video. what is the best way to remove "frozen" lag bolts? I'm considering spraying a product like PB Blaster around the base of the screw but want to ensure this is something you would advise.

[AtypicalPaul]

Could these be used with long lag screws where they stick out from the wall to hang a floating shelf on? Or do they need to be fully tightened down onto something?

[shoovjk]

It tells you on the shield what size of hole to drill. Look for the little circle with the hole size in it.

[bibo]

Once the lag screw is screwed in the lag shield, can you remove and re-screw the lag screw or this is a one time use? Thanks

[senaisenai]

Great video! Super helpful. Thank you. Question: How long should the lag shield be for a 3 in lag bolt?

[MAHOCA-gr]

Can I use this for punching bag wall mount? Can it hold the weight of 100lb? I'm planning a cantilever wall mount.

[jamespolucha]

Will this work for red brick? I’m installing a shelf for a fire place mantle

[davidbrandel]

Would those work on stucco or are they just for concrete?

[AliasHSW]

Can the lag screw in system be remove and reuse to mount/dismount objects repeatedly? Should 1/2 of the shield be epoxied in the concreted hole if the screw is to be removed/mounted repeatedly? TIA

[iamthecheese]

Looking for something that can be permanent but reusable. For instance, I want to use a pop up canopy in my driveway when working on cars, so i need to anchor it down. Can't use stud type anchors because i don't want to be driving over pieces of metal sticking up out of the ground for obvious reasons. So i need something like an anchor well that I would leave in the ground, set up the canopy, bolt down and then be able to unbolt to take down the canopy and leave the wells until next time i need them. (Of course reinserting the bolts to ground level to keep debris out of them) Would these work for that purpose? Like a permanent anchor with intermittent use.

[raywu]

Brick, perhaps porous: Best anchor type to use? Will Strike Anchor works on bricks since striking it expands the inserted/slipped in anchor?

[NetanyaGila]

I'm installing a 2×4.
My shield is 1 1/2 but my screw is 3 1/2. 1/2 longer than I need. Can I still use it?

[JulesBartow]

Do these work in cinder block concrete masonry units (CMUs) or should they only be used in regular concrete?

[gerardorosado]

Great video, I need a little bit help knowing if this is what I need for my project. I want to hang a big frame is around 20 pounds heavy. It will go inside the house in the wall that has concrete. So is the concrete plus the drywall. Is the lag screw the best option. I want something that will hold more weight than what i have. I bought the cobra 253S, is 5/16''Lx2-1/4''. Thanks for your help.

[heroknaderi]

Thank you for this video I have a greenhouse with 2 cinderblock pillars wich i am installing a mini garage door i am building with wood and the pulleys for the spring cable will be fastened directly to the pillars the way I built the greenhouse.

[frankmatthews]

Are these good to attach burglar bars to concrete?