Fastening 2x4 to cinderblock

[TomC750]

I am fastening 2x4s flat against cinderblock wall with 1" XPS between 2x's and wall. I started to use 1/4 "by 4" Tapcons so I would have sufficient length into the block. However, most would strip out. I had used a 3/16 masonry drill. I then went to a 5/32 drill and my impact driver would stall out before the Tapcon was all the way in. I decided to use 3 1/2 " cut masonry nails, sometimes they did not hold. Years ago I used spring nails into a concrete wall with good results. If I had any left I would try that, but can't find a source for them now. My blocks are very dense, so I don't think that is a factor. Thoughts anyone?

 

[Leaflessshadetree]

I've used tapcons a few times but often with results liek you are having (broken screws or stripped out holes). I usually end up filling the failed hole with wood or epoxy then installing the screw.

A powder actuated nailer is a lot easier/faster.

There are several types of anchors (which are probably a sturdier connection) but take more time.
Another option:

 

[The Cobbler]

do your 4" tapcons have threads back far enough to grab ? also don't over tighten the screws. snug is good

 

[vwpieces]

I usually use my M12 hammer drill.
I get better results on high or #2 speed and clear dust frequently.
Hollow parts parts of the cinder block of my shop tend to not hold well.

 

[The Bean]

"My blocks are very dense..."

The term Cinderblock refers to lightweight, less dense blocks, originally incorporating coal ash. Are you sure you don't have full strength CMU?

 

[TomC750]

My wall is just short of 3 years old, yes, CMU I would think. That term is not used around here. They call them cinder blocks, even though they are not. I was making a mistake by predrilling with the 5/32 masonry drill as I just discovered. I tried again without predrilling and it held well. I guess I went to predrilling as I have an injured wrist and just trying to make it a bit easier. I was using a heavy hammer to drive, but I came up with the idea of making a driver out of the drift for my air impact. I drilled a 7/16 nut to 1/2" (I did not want the OD to be too big which is why I used 7/16), left about 1/3 of it out past the end of the drift. I then welded it fast. That provided a "cup" so the driver would not slip out of the nail. It worked really well.
As an aside, I ran out of masonry nails, and buying the rest from Lowes would have cost $48. The local hardware was out but would have been only $18 if in stock. I have more coming Tues. I guess I am OK for now, and if I have any more trouble I know where to go!

 

[TomC750]

do your 4" tapcons have threads back far enough to grab ? also don't over tighten the screws. snug is good

Yes

 

[TomC750]

I've used tapcons a few times but often with results liek you are having (broken screws or stripped out holes). I usually end up filling the failed hole with wood or epoxy then installing the screw.

A powder actuated nailer is a lot easier/faster.

There are several types of anchors (which are probably a sturdier connection) but take more time.
Another option:

I have a powder actuated nailer, but not used it in years, had problems with jamming. I will watch video. Very interesting, and cheap to boot. I recall doing this many years ago when I was desperate in a repair situation. Thanks.

 

[lolaetype]

I am fastening 2x4s flat against cinderblock wall with 1" XPS between 2x's and wall

I've never had to do this so I'm just speculating.

Would toggle bolts work in that application?

 

[rancherbill]

There a million brand names but get these.

Drill the hole with a SDS drill and then put the screw in with you impact drives. Super fast and super strong.

 

[billconner]

I had very good success with tapcons, hammer drill, and impact drill this summer. I don't recall sizes but got drill size as called out on tap on box.

 

[NUTTSGT]

My wall is just short of 3 years old, yes, CMU I would think. That term is not used around here. They call them cinder blocks, even though they are not. I was making a mistake by predrilling with the 5/32 masonry drill as I just discovered. I tried again without predrilling and it held well. I guess I went to predrilling as I have an injured wrist and just trying to make it a bit easier. I was using a heavy hammer to drive, but I came up with the idea of making a driver out of the drift for my air impact. I drilled a 7/16 nut to 1/2" (I did not want the OD to be too big which is why I used 7/16), left about 1/3 of it out past the end of the drift. I then welded it fast. That provided a "cup" so the driver would not slip out of the nail. It worked really well.
As an aside, I ran out of masonry nails, and buying the rest from Lowes would have cost $48. The local hardware was out but would have been only $18 if in stock. I have more coming Tues. I guess I am OK for now, and if I have any more trouble I know where to go!

Am I understanding that you are "pounding" the tapcons in ?

 

[greatreset]

Tapcons the only way to do it.

 

[TomC750]

Am I understanding that you are "pounding" the tapcons in ?

No! I am not pounding tapcons in! I switched to masonry nails due to the problems I had with the tapcons as previously outlined.. Interestingly, where I did not have foam behind the 2x's the 3/16 tapcons worked fine. The 3/16 tapcons would have been my choice for the entire job had they been available in a 4" length.

 

[TomC750]

Tapcons the only way to do it.

Well, Did you read my previous posts about them stripping?

 

[TomC750]

I had very good success with tapcons, hammer drill, and impact drill this summer. I don't recall sizes but got drill size as called out on tap on box.

I used drill furnished with Tapcons, and is the correct size, 3/16 for 1/4 inch Tapcons. 5/32 is too small.

 

[Hank11]

Shooting them in with a powder actuated gun will be fast and easy.
Also, Tapcons work better with the hole cleaned out and a stout impact driver.

 

[The Cobbler]

I have way more blowouts with powder guns than with 1/4" tapcons in concrete block

 

[NUTTSGT]

No! I am not pounding tapcons in! I switched to masonry nails due to the problems I had with the tapcons as previously outlined.. Interestingly, where I did not have foam behind the 2x's the 5/16 tapcons worked fine. The 5/16 tapcons would have been my choice for the entire job had they been available in a 4" length.

It looks like the foam behind the 2x4s is your problem. I have never seen or heard of anyone using foam behind a 2x or firing strip.

I would guess the foam is not allowing the tapcon to bite firmly into the concrete block and allowing it to strip out.

 

[K'ledgeBldr]

If this is a basement- I wouldn’t attach any framing to the walls; especially CMU.

attach foam board to wall with adhesive, seal all the seams with seam tape. Frame walls and stand in front of foam board, attach to floor and floor joists above.

Don’t make a mountain out of a mole hill-

 

[Hank11]

If this is a basement- I wouldn’t attach any framing to the walls; especially CMU.

attach foam board to wall with adhesive, seal all the seams with seam tape. Frame walls and stand in front of foam board, attach to floor and floor joists above.

Don’t make a mountain out of a mole hill-

This is good advice. ^^^^^^^^^^^^

 

[The Bean]

 

[cgrutt]

If this is a basement- I wouldn’t attach any framing to the walls; especially CMU.

attach foam board to wall with adhesive, seal all the seams with seam tape. Frame walls and stand in front of foam board, attach to floor and floor joists above.

Don’t make a mountain out of a mole hill-

Yep.

Believe you also need to fireblock and draft stop the XPS every 10' and between ceiling and floor per Fire code.

 

[vwpieces]

That is not a joke...
Recently I had to remove some Old Goodyear hose/belt hanger hooks from the wall of an old auto repair shop. Boards were nailed into the concrete wall with square nails. What an evil task to get them off. I ended up prying the boards from wall slightly, just enough to flex and bend nails till they broke off. Any amount of trying to pull the nails from wall only damaged the boards.

 

[TomC750]

I've used tapcons a few times but often with results liek you are having (broken screws or stripped out holes). I usually end up filling the failed hole with wood or epoxy then installing the screw.

A powder actuated nailer is a lot easier/faster.

There are several types of anchors (which are probably a sturdier connection) but take more time.
Another option:

This is good advice. ^^^^^^^^^^^^

I have had advice to the contrary... The well regarded contractor who built the house had the same plan. The basement is bone dry. sealed up on the outside like I have not seen before. I did the same thing on my house I built in 1992 and never saw evidence of any problem. In fact the present owner did some changes recently to the basement rooms (reframing) and complimented me on the job. No evidence of moisture or another problem. Too late now, my present job is half done. And going on 83 I am mostly done. I had good luck with the 3/16 Tapcons today, put in around 50. I think the 1/4 inch ones would work better with a slightly smaller drill, especially in block. I don't think I have ever seen a 11/64 masonry drill however!

 

[TomC750]

Yep.

Believe you also need to fireblock and draft stop the XPS every 10' and between ceiling and floor per Fire code.

Don't understand the "don't make a mountain out of a mole hill..." I did tape the seams with Zip tape.

 

[cgrutt]

Don't understand the "don't make a mountain out of a mole hill..." I did tape the seams with Zip tape.

Sorry that wasn't my comment I was agreeing with suggestion to build freestanding wall in front and not attaching to block.

As far as I know the problem with XPS is its very flammable so you shouldn't have one continuous stretch of it that, if caught on fire, would rapidly spread to everything it touches. You need (well, should anyway) to have fire blocking between every 10' section and between walls/ceiling to contain spread of fire. Same goes for draft stopping, which needs to go directly to concrete wall within any cavities to prevent any drafts, which could accelerate the spread of fire. Not an expert on this just my understanding.

 

[TomC750]

That is not a joke...
Recently I had to remove some Old Goodyear hose/belt hanger hooks from the wall of an old auto repair shop. Boards were nailed into the concrete wall with square nails. What an evil task to get the

It looks like the foam behind the 2x4s is your problem. I have never seen or heard of anyone using foam behind a 2x or firing strip.

I would guess the foam is not allowing the tapcon to bite firmly into the concrete block and allowing it to strip out.

m off. I ended up prying the boards from wall slightly, just enough to flex and bend nails till they broke off. Any amount of trying to pull the nails from wall only damaged the boards.

I did the same thing in the Auto Parts store building I owned! That was a block wall as well. I got the nails out with a nail puller with a piece of pipe on the end. It pulled out little chucks of block.

It looks like the foam behind the 2x4s is your problem. I have never seen or heard of anyone using foam behind a 2x or firing strip.

I would guess the foam is not allowing the tapcon to bite firmly into the concrete block and allowing it to strip out.

I mistyped, 3/16 Tapcons, not 5/16. The 1/4 x4" Tapcons are long enough. I experimented with a thinner wood member, same problem. And foam behind a 2x is common and provides a better vapor barrier on an above grade wall.

 

[TomC750]

Sorry that wasn't my comment I was agreeing with suggestion to build freestanding wall in front and not attaching to block.

As far as I know the problem with XPS is its very flammable so you shouldn't have one continuous stretch of it that, if caught on fire, would rapidly spread to everything it touches. You need (well, should anyway) to have fire blocking between every 10' section and between walls/ceiling to contain spread of fire. Same goes for draft stopping, which needs to go directly to concrete wall within any cavities to prevent any drafts, which could accelerate the spread of fire. Not an expert on this just my understanding.

Appreciate the comment on this. Thanks. When house was built inspector said I was all set with barrier. Will check.

 

[Uncle murph]

I am fastening 2x4s flat against cinderblock wall with 1" XPS between 2x's and wall. I started to use 1/4 "by 4" Tapcons so I would have sufficient length into the block. However, most would strip out. I had used a 3/16 masonry drill. I then went to a 5/32 drill and my impact driver would stall out before the Tapcon was all the way in. I decided to use 3 1/2 " cut masonry nails, sometimes they did not hold. Years ago I used spring nails into a concrete wall with good results. If I had any left I would try that, but can't find a source for them now. My blocks are very dense, so I don't think that is a factor. Thoughts anyone?

Tapcon 2 3/4 by 1/4”,I’ve never had any problems.

 

[dogdog]

I am fastening 2x4s flat against cinderblock wall with 1" XPS between 2x's and wall. I started to use 1/4 "by 4" Tapcons so I would have sufficient length into the block. However, most would strip out. I had used a 3/16 masonry drill. I then went to a 5/32 drill and my impact driver would stall out before the Tapcon was all the way in. I decided to use 3 1/2 " cut masonry nails, sometimes they did not hold. Years ago I used spring nails into a concrete wall with good results. If I had any left I would try that, but can't find a source for them now. My blocks are very dense, so I don't think that is a factor. Thoughts anyone?

Tapcon won't do the job, if it is ripping out of the wall on some... it is fine for small stuff... you need those bolts with the epoxy and a mesh finger.. chemical anchoring stuff from hilt or redhead maybe...

Hilti 0.63 in. x 3.35 in. HIT Composite Mesh Sleeves for Chemical Anchoring (20-Piece) 375982 - The Home Depot

Take your towing jobs to the next level with the help of this affordably priced Hilti HIT Composite Mesh Sleeves for Chemical Anchoring.

www.homedepot.com

or something like these sleeved but you have to estimate the thickness of your wood and cinder block...


(you will have to check the length you need)

Hilti 1/2 in. x 2-1/4 in. Hex Nut Head HLC Sleeve Anchors (5-Pack) 3512339 - The Home Depot

Update your car with the help of this Hilti Hex Nut Head HLC Sleeve Anchors.

www.homedepot.com

The approximate 80' of two tier shelves/tables I hung with 2x4 anchored using the mesh and those sleeves (was trying to use tapcon and it ripped out of the wall when I screw them in). Holds hundreds of lbs fine, if you build it right. Seems to be cheaper way back 8 years back...

 

[KenC]

Tapcon 2 3/4 by 1/4”,I’ve never had any problems.

That would provide 1 1/4" into the block if just fastening a 2x. But the OP has an inch of foam also, so a 2 3/4 would only engage the block 1/4".

IME drilling for Tapcons only works if I use an SDS type drill. Others tend of drill oversize holes and strip.

 

[TomC750]

Tapcon won't do the job, if it is ripping out of the wall on some... it is fine for small stuff... you need those bolts with the epoxy and a mesh finger.. chemical anchoring stuff from hilt or redhead maybe...

Hilti 0.63 in. x 3.35 in. HIT Composite Mesh Sleeves for Chemical Anchoring (20-Piece) 375982 - The Home Depot

Take your towing jobs to the next level with the help of this affordably priced Hilti HIT Composite Mesh Sleeves for Chemical Anchoring.

www.homedepot.com

or something like these sleeved but you have to estimate the thickness of your wood and cinder block...


(you will have to check the length you need)

Hilti 1/2 in. x 2-1/4 in. Hex Nut Head HLC Sleeve Anchors (5-Pack) 3512339 - The Home Depot

Update your car with the help of this Hilti Hex Nut Head HLC Sleeve Anchors.

www.homedepot.com

The approximate 80' of two tier shelves/tables I hung with 2x4 anchored using the mesh and those sleeves (was trying to use tapcon and it ripped out of the wall when I screw them in). Holds hundreds of lbs fine, if you build it right. Seems to be cheaper way back 8 years back...

I have used Redheads a lot, but not Hilti's. Have not seen them in some time. I am all set for now as I have what works. Thanks.

 

[TomC750]

That would provide 1 1/4" into the block if just fastening a 2x. But the OP has an inch of foam also, so a 2 3/4 would only engage the block 1/4".

IME drilling for Tapcons only works if I use an SDS type drill. Others tend of drill oversize holes and strip.

OK, using regular masonry drills and working great with the 3/16 Tapcons. Thanks

 

[TomC750]

Don't understand the "don't make a mountain out of a mole hill..." I did tape the seams with Zip tape.

Appreciate the comment on this. Thanks. When house was built inspector said I was all set with barrier. Will check.

What is typically used for a barrier? 1/2" sheetrock?

 

[Mike in Ohio]

If this is a basement- I wouldn’t attach any framing to the walls; especially CMU.

attach foam board to wall with adhesive, seal all the seams with seam tape. Frame walls and stand in front of foam board, attach to floor and floor joists above.

Don’t make a mountain out of a mole hill-

Not to hijack, but what kind of adhesive do you recommend? I may be putting up some foam board in a detached block building this spring. The ceiling and wood framed walls are insulated, but the exterior block walls need something.

 

[billconner]

Not to hijack, but what kind of adhesive do you recommend? I may be putting up some foam board in a detached block building this spring. The ceiling and wood framed walls are insulated, but the exterior block walls need something.

I've never done it but having read and watched you tubes, I'd consider spray foam first - both foam to wall and GWB to foam. There are adhesives designed for this of course.

 

[GirlnAgarage]

I've had good luck w Tapcons. If you aren't already, blow out/vacuum the drilled holes. Might have debris causing an issue when you tighten down. Of course, explore the possibility of material composition causing a problem like the guys mentioned above.

 

[ycgoat]

This may be a bit late, but For CMU and brick walls, I use a lead anchors and a hollow wall set tool. It puts a threaded nut flush with the surface regardless of the a hollow in the wall or a hole drilled too deep. I have a 1/4"x20 and 3/8"x 16 tool

https://www.amazon.com/dp/B07R7P2XJK/?tag=atomicindus08-20

 

[marak]

Not to hijack, but what kind of adhesive do you recommend? I may be putting up some foam board in a detached block building this spring. The ceiling and wood framed walls are insulated, but the exterior block walls need something.

I refinished my basement just like the OP, except I fastened the XPS to the concrete using spray foam then used slats of wood to apply pressure to the XPS. Worked perfectly. I originally forgot to add the firebreak, so had the pleasure of removing some XPS...that was fun.