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anchor sole plate to concrete slab

byrd48's picture

I'm installing a wall section on an old concrete slab.  I bought the tapcon 1/4" anchors with their recommended drill bits.

I have a cheap Black and Decker 1/2" hammer drill.  This setup is just not working.  I have drilled maybe 3 holes and have already gone through all 4 bits.  In addition, Tapcon recommends drilling the hole 1/4" deeper than the fastener, but for the 3 3/4" fasteners, the drill bit is not long enough.

Should I try a different drill bit, or do I need to rent a rotary hammer?

I also thought of the Remington powder actuated fasteners.

Last but not least, I've never tried it, but can you nail into concrete with a hammer?



I'm assuming this wall isn't (post #205064, reply #1 of 8)

I'm assuming this wall isn't load bearing or otherwise in need of real anchoring because if so you need real anchor bolts.


If you don't need real bolts.......

Tapcons are great but can be real persnickity to install. Old concrete can be really hard and the hole has to be just right for them to work.

There are many types of drive- in-a- hole-wedge  type anchors that are  user friendly. They come in different sizes but ones that fit a 3/8" hole drilled through the plate and floor might do your task. Some expand as you pound them in, others as you tighten the nut. Seems to me the latter are stronger.


With a sharp bit your described drill should easily do the job.

And to answer the question, yes you can drive nails into concrete. Concrete nails are all that holds a lot of houses to the slab that were built in bygone days. Generally speaking I'd say this technique is nearly as effective as wishful thinking. Maybe even less so in old concrete.


You can drive two nails (post #205064, reply #2 of 8)

You can drive two nails (side-by-side) into concrete, if you drill a hole first.

Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

P.A.D or (post #205064, reply #3 of 8)

rent the rotary hammer.  It'll make easy work of it. 

Do not lean on it, let the hammering action work, which it does by rotating.  Unlike your hammer drill, you do not put all your weight on the drill.

Continuously go in and out (to clear the hole) and yes, go deeper than the length of the fastener.  If you want a little better ease of driving-use an impact driver to run them in, use the hex head type, not the phillips and lube the fastener with some wax.

Best of luck.

A Great Place for Information, Comraderie, and a Sucker Punch.

Remodeling Contractor just outside the Glass City.


I'm glad I posted here, I (post #205064, reply #5 of 8)

I'm glad I posted here, I don't know what I was thinking trying to use tapcon screws in the first place.

I rented the rotary hammer and got half inch wedge anchors.  Wow, that drill works like a charm!

Glad it worked (post #205064, reply #7 of 8)

and come back often, there's talent here and you of course can contribute.  Not a bad way to waste time.........

or learn something.  And learning something doesn't end in graduation or a lifetime in the trades.

Best of luck.

A Great Place for Information, Comraderie, and a Sucker Punch.

Remodeling Contractor just outside the Glass City.


P.A.D. (post #205064, reply #4 of 8)

There are several powder actuated devices out there that will do the job for you. Hilti and Ramset are the two big guys on the market, but there are others sold at the big box store that are as effective and cheaper. The single shot type that you strike with a hammer comes to mind, but ICRC a brand name.

Assuming you are using treated lumber for plates to meet most building codes requirements, the fasteners (nails) for PAD systems are approved for non-load bearing walls and ACQ lumber. The trick in using any pad system is selecting the right fastener length and charge.  I have used them for years to attach plates to both old and new concrete as well as structural steel. Just place your plate on the chalk line, hodl it down firmly and fire the pad, your done. BTW the plate must be in full contact with the slab at the point  the fasteners goes in. A gap beneat it will cause a blow out of the surface concrete and enough bounce for the fastener to hold.

Tappcons say they are ratted for use in ACQ lumber, but are not approved fo anchoring load bearing walls. For that you need drive in wedge type anchors of 1/2" diameter (minimum) and properly spaced for load bearing walls. 1/2" diameter anchors are also the minimum size allowed for use in any treated lumber. Smaller than taht and the ACQ stuff will destroy the anchor in a few years if exposed to any moisture. They will last longer in dry locations,but who knowes what longer is?

Your hammer drill should do the job, but as Calvin pointed out, a rotary hammer is faste and easier ton you. Longer bits are available for you hammer drill. I'm not so sure you can find the in the smaller sizes for SDS drive rotary drills, depends on the size of the drill and the manufacturer I think. The key to using your hammer drill is slow steady pressure, but not leaning on it, and staying straight. Wobbeling out the hole from leaning on the drill to hard will mean that the tappcon will strip easily when you try to drive it in.

DanH mentioned the two nails in a drilled hole trick is often used by concrete guys when laying down plates for foundation wall forms. While it does work. it has very little uplift resistance (not needed in form work) and if you are using ACQ treated  plates the nails will be eaten up in less than a year. For non treated lumber however it is the fastest and cheapest method to use, but you may need to go back and tightened up the nail pairs as you frame on top of the plates.

Thanks Dave, The anchor (post #205064, reply #6 of 8)

Thanks Dave,

The anchor wedges I got were galvanized, so they should last a good long while.

I'm still amazed the previous walls had no anchorning whatsoever on the sole plates (and were untreated to boot)

untreated (post #205064, reply #8 of 8)

The treated lumber in contact with concrete is a fairly recent code requirement. Maybe as much as 20 years ago. Prior to that sill and sole plates were  common lumber speices. The only treated lumber in my area in the earl seventies was wet treated (soaked), not pressuretreated, and we wouldn't even use it on porches. The tuff was so bad that it literally went wild on you as it dried out. 

I worked on many homes with untreated lumber plates and porches (now we call them decks). I even did repair work for a major pesticide company, and you would think with all that untreated lumber in homes I would have been covered up with work. Not so. Treated lumber has it's pluss' , but IMO it is not the end all and be all that is touted to be. This newest version is a PITA because it is so corrosive to fasteners. It has spawn at whole new market of products , and again IMO the jury will be out on them for years to come.

Heck, I finished many a basement with common lumber and the only anchor I used in a plate was a 1\2" dowel ro driven into a 1\2" hole drilled through into the concrete and an couple of 8d nails driven into them. Never had a callback because the plate came lose. Water is the ennemy, and as long as a basement id dry, I wouldn't  hesitate to use the method agian.