Favorite concrete screw?

[Ken Platt]

Folks - I don't have much experience with concrete fasteners - the last time I used a screw brand called "Phillips II Kwiktap" and was underwhelmed. I had quite a few not drive in properly and were stripped and unusable when I pulled them out (could be operator error also, but I tried to be careful to drill a deep enough hole and both blow out and vacuum out the dust before driving the screw).

This go round, I will be driving a good number of these to hold up a combination studwall/insulation panel product (it's called Insofast). So I thought I'd see if there was any experience with the various brands of screws. I'll need 3/16" x 3 1/4" long.

Also, the screw type recommended by Insofast is flat head phillips drive, which I hate. McFeely's has a house brand screw with a combination (phillips/square )drive - anyone have experience with it?

All pointers appreciated -

Ken

[Stan Calow]

I've driven a lot of Tapcon screws. Not had one pull out. They come with various heads.

[Dave Cav]

My limited experience has been with Tapcons, too. They seem to work pretty well and are readily available at HD.

[Paul F Franklin]

I've not had as good luck as Stan with Tapcon's. When I insulated my basement I drove a couple of hundred of them into hollow concrete block. Probably 15% of them stripped and had to be redone. And more than a few snapped off. I put it down to the variation in block. If you hit a piece of aggregate the screw can snap off. If you are in the thinnest part of the block, its very easy to strip the hole. I gave up trying to use them to secure the wall bottom plates. The 40 year old concrete was just too tough and I was snapping every other screw. And I was drilling an extra inch deep and blowing out every hole.

Having said that, I haven't found any concrete screws that work better. Make sure you use a driver with a clutch or you will strip more of them. AFAIK, tapcons only come in Phillips or hex head (which are obviously not flat head). If you are using 3/16 screws, pick up some 1/4 too, to use when you strip one out. I think those panels have designated areas for the screws, so you can't just move over an inch.

I'd use construction adhesive for the main fastening, and just use enough screws to hold the panels tight while the adhesive sets.

[David Kreuzberg]

+1 for Tapcons. Be sure to drill the hole a little deeper than the length of the fastener with the correct size bit for the fastener - with a hammer drill, not a standard drill. An impact driver also works very well to seat the fastener.

[Rich Engelhardt]

1/4" Tapcons - I find the 3/16" ones strip out & shear the heads off.

You can easily drill 1/4" holes in concrete, stone, brick, block or mortar using a hammer drill.

Anything larger than 1/4" & you might as well buy or rent a SDS Rotary hammer.

Having said that - for putting a bottom plate down on a concrete floor - such as a basement - I just use a few dabs of PL adhesive (Locktite Masonry) & stick in a few 3.5" galvanized framing nails with my Bostitch F28WW framing nailer. The F28WW is a beast & it's rated for masonry use right out of the box.

[Malcolm Schweizer]

I live in a stone house with a concrete addition. I use tapcons and agree with the above regarding 1/4" being a better option. I own a few SDS+ hammer drills due to my situation. You really need one of those and drill the hole deeper than the screw by a good bit. Don't vacuum the dust out of the hole- just make the hole deeper. The dust actually helps the screw bite.

I use the stainless Tapcons. I have had a number of them fail- you really have to torque them just right. I have yet to find a screw that doesn't have this issue. They just don't make stuff like they used to.

I have started using a nail gun with a .22 cal powder charge whenever possible in lieu of Tapcons. Of course there are times a nail won't work, but consider that if hanging studs to concrete or other times a nail will do.

[Steve Rozmiarek]

There is no fast way to do concrete screws that I'm aware of. Tapcons are the usual choice on the construction scene here. That being said, Malcolm pointed out what we usually try to do if a bunch of fasteners are needed. Hilti or Ramset (and others) powder actuated drivers are much faster. The only downside to them are a bit of unpredictability on drive depth but once you get the right charge chosen, they go really fast. You'll save quite a lot of time by using them on a basement furring job. I'd recommend the Ramset semi auto that has the charges on a strip.

[Tim Bueler]

Are you dead set on screws? Along with the powder actuated fasteners already mentioned there are also drive pins. You will need a roto-hammer with a 1/4" bit. I've been out of that part of construction for a while but we used to use drive pins all the time. There was also a duplex head drive pin available for potential removal.

[Bradley Gray]

1/4" tapcons with hex head

[James Pallas]

I like hex head tapcons for speed. For myself my all time favorites are red heads wedge type. I know old school.
Jim

[Ken Platt]

Thanks folks. Looks like I'll just go with the tapcons.

The 3/16 size is what is recommended by the insofast folks, so that's where the sizing comes from. I'll be using glue also, some of the wall areas are in good shape for that to hold, but I'd say a good half or so the surface quality of the wall doesn't inspire confidence in glue working by itself, thus the screws.

I appreciate the tip on using the 1/4 inch for when a 3/16 strips out. Hadn't occurred to me.

Ken

[Osvaldo Cristo]

I live in a country where our standard material for walls are concrete, concrete blocks and masonry.

Although I have tried Spax and Tapcon's, the single way I found to have consistent results are the old method of using nylon sleeves with correct boring dimensions and will support bigger load easily.

I recognize Spax and Tapcon's are way more convenient to use and from my own experience they can do a very good job... *sometimes*...

[Aaron Rosenthal]

Ken, I've used almost everything from Simpson concrete fasteners to topcon to sleeve fasteners; one thing I suggest no matter what, once you pre drill, and I REALLY suggest a rotary hammer, make sure you vacuum out the hole. Makes life much easier.

[Frank Pratt]

The key to successfully driving concrete screws is to use an impact driver rather than a drill driver. The pulsing nature of the impact driver means much less cam out with the bit. There's still the issue with threads stripping though. Concrete screws are definitely not my favorite concrete anchor.