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fastener into featherlite concrete question

Hi,

I am trying to fasten some wooden planks to the concrete floor in our third storey apartment. The 3 storey building is built of two by fours in the usual way. Between the storeys is a layer of featherlite concrete. I have tried #8 concrete screws and also sheetrock self-tapping screws. Sometimes these hold but more often the concrete crumbles and will not hold the fastener securely.

I am writing to ask if there are other ways of securing a fastener to featherlite concrete. Perhaps some kind of anchor which will stay in place and hold a fastener.

Thank you in advance for your suggestions.

Mike Eisenstadt Austin, Texas

Reply to
Mike Eisenstadt
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I'd try either a single expansion or double expansion anchor:

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Reply to
Nova

Mike,

That lightweight concrete is only there for soundproofing and fire resistance. It is only about 2" thick. Get some screws long enough to go all the way through to the plywood underneath.

Question: Should you be doing this in an apartment? Are you renting?

The reason that I ask is that those floors are very crumbly to begin with and any penetrations make them crack even more. I have replaced thousands of square feet of this stuff. When we are remodeling (in condos that are built the same way), we usually use an epoxy application to bond everything together, then glue and attach new wall plate both to the lightweight (with construction adhesive) and to the plywood substrate (with screws, mostly to hold in place until the glues dries). The lightweight cannot be trusted to hold anything, or even to hold together, without help.

Reply to
Robert Allison

Jack,

Thanks for your suggestion. It seems very promising.

Mike Eisenstadt

Reply to
Mike Eisenstadt

We own the apartment. Of course I don't want to go through the ceiling of the apartment downstairs so I don't think I should try to reach the plywood above the downstairs apartment's ceiling.

I should explain further what the project is. I mean to install a manufactured wood pergo type floor over the wall-to-wall carpet and subpad which is to be left in place. I want to leave it in place to decrease any noise transmission to the apt below caused by us walking around (with our shoes off). I want to secure the pergo floor to the cement so it wont float up and down when walked on. I know that the pergo will expand and contract so I have made prevision for some movement by setting a 1 1/4 flat washer into some of the pergo strakes with a half inch hole drilled through the strake underneath the flat washer. A 1" o.d.fender washer rides on the flat washer and through the fender washer a flat head fastener secures to the cement. This permits the strake to move a bit underneath the fender washer and fastener. The fender washer and fastener slides on the flat washer. I would like to try the some kind of expanding anchor to see if that would hold. The flathead fastener is countersunk so only the 1/16" thickness of the fender washer is proud of the strake. The carpet nap is the springy type. The fastener just has to be tight enough to compress the carpet. Perhaps a single expansion or double expansion anchor would work with a flathead machine screw to expand it. Or one of the many other anchors available from the Concrete Fasteners company which was referenced in Jack Novak's email.

I might mention that the lightweight has held together for 40 years.

Thanks for your useful comments.

Mike Eisenstadt Austin, TX

Reply to
Mike Eisenstadt

That seems to me like you are asking for major trouble down the road! Does the manufacturer of the flooring permit installation over carpet?? I would remove the carpet and pad, and start from there. Surely the manufacturer has a underlayment of some sort for this purpose! Greg

Reply to
Greg O

What is the possible trouble? The manufacturer of this product, Harmonics, does advise removing carpet and underpad and they do sell a plastic pad to put under the floor. Not to do so voids their 25 year "guarantee." This might make some sense if one was installing on a cement slab at ground level where the hydroscopic nature of cement would buckle the floor in a wet season. But I am 3 storeys up and there would be a pad and a carpet between the floor and the concrete.

Mike Eisenstadt

Reply to
Mike Eisenstadt

You won't, there is the carpet, then the pad, then the plywood, then at least a 2x12, then the drywall on the ceiling below. There is NO WAY that you could go through the ceiling below with anything less than a

12" screw.

That is crazy as hell. Sorry, but that is the only way to describe it. You are on your own on this one. Good luck, you are going to need it.

Some of the lightweight that I have replaced was there longer than that.

Reply to
Robert Allison

The moisture is NOT the prime reason for your idea voiding the warranty, it's the flexing of the "planks" on the current carpet. The pad that they make for underlayment is just think enough to allow some give and flex, but not so much as to actually allow the plank to snap.

But what the hell, if you know the product better than the folks that made it, have fun.

Reply to
The Davenport's

Good luck on installing your floor! There is no way it will hold up with all the flexing it will deal with because of the "cushion" of the carpet and pad. Trust me, you are asking for certain failure!! Moisture is far from the problems you will see. The plastic pad they sell is there to also deal with noise transmission, not just moisture. Greg

Reply to
Greg O

The instruction warn against moisture problems if pad is not used. Yes, the manufacturers know more about the product than I do, but I sure as hell know the product better than you do.

Mike Eisenstadt Austin, TX

Reply to
Mike Eisenstadt

"Mike Eisenstadt" wrote

LOL ... Advice requested, advice received, argue about advice received ... you a drummer, or just a dumb shit?

Reply to
Swingman

ROFL. He's gonna do what he's gonna do.

Reply to
Tanus

What I love the most about things like this is when the guy...yes, I'm comfortable with that generalization in this newsgroup...ignores the parts that HE said about the warranty being voided, but I'm the a$$hole that doesn't know the product.

Oh, well...it's good for a laugh on a monday

Mike

Reply to
The Davenport's

Being a drummer, I resemble that. And don't tell me I'm illiterate. I can prove my parents were married.

Reply to
Robert Allison

Since this guy is in Austin, he may be the same guy that did one of the weirdest floors I have seen. I was requested to come and replace some vinyl that had developed holes.

I figured to find some old vinyl that had worn through, but noooooo! I found a pantry that had been carpeted and the guy had just lain vinyl over the carpet and used roofing nails to attach it. The nails were placed on the corners of the pattern and were nearly hidden by the pattern except that the vinyl was pulled down tight at those points.

Walking on the floor had caused tears and holes (I guess from high heels). I explained that this was not proper and that I would have to remove both the vinyl and the carpet if he wanted me to reinstall new vinyl. He thought that I was trying to rip him off by doing more work than was needed!

I didn't do that job.

Took me a while to figure out what the hell the floor was in the first place. It was kind of cool in a way. Real soft vinyl!

Reply to
Robert Allison

The amount of gratuituous abuse from strangers on news groups is staggering.

2" sheetrock screws are holding tight into the featherlite concrete. I will tighten the strakes down later when the flooring is monolithic. The cheap high pile floor-to-floor carpet just needs enough force to hold its high pile down.

These are Harmonic brand manufactured wood strakes. Costco sells them real cheap.

I soaked a piece of this stuff in water for a week. No apparent difference. The grain is actually a photograph of random maple pieces. The photograph is embedded in a very thin plastic ply over the wood product (that's what Harmonics calls it).

Mike Eisenstadt Austin, Texas

Reply to
Mike Eisenstadt

Maybe. Maybe not.

However, Swingman put it very well. You asked for feedback and got it. It wasn't what you wanted to hear. And you swung back.

You think the Wreck is abusive? Try just about any other group. And to tell you the truth, calling a spade a spade is far from abusive. Most who responded said it was a bad idea.

Think about what you just did. You came in here, thinking (rightly) that you were consulting with some professionals. And you got professional advice. Not a single supporting post for your idea. Even the manufacturer advises against it.

So, you're bucking conventional wisdom, manufacturer's specs and good common sense and whining that people think your idea is idiotic.

Good thing this stuff is cheap at Costco.

Reply to
Tanus

Good for you! That should last at least a week. Although I have been in the construction business for almost 40 years, you are obviously more of an expert on this stuff than I am.

Never heard of Harmonic. But then I have only installed about 150-200 thousand square feet of flooring. I obviously still have a lot to learn.

And why would you be worried about water?

Reply to
Robert Allison

Because the OP did the plumbing too? Greg

Reply to
Greg O

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