Fireplace project pt 2: Installing the hearth questions (carpetting related, too)

Back to the SDMB for my fireplace project. You helped me stain my mantle, now I turn to you over those home improvement sites for advice on one more detail:

I need to install the hearth onto the floor. I need to remove a portion of the carpet and set the slab of marble down. She’s a big piece, at six feet long. That isn’t the issue really. I am setting in on cement (since this portion of my home isn’t over the basement, it’s going right on the slab).

My concern is what to do with the carpet so that it fits nicely AND so that when the carpet is replaced someday, the new carpet will be able to be installed so that is fits nicely too.

What I was thinking:

Even though I can put the marble right onto the concrete slab (after removing carpet section), I am thinking it’d be better to add a 1/4 inch backerboard underneath which is trimmed back all around by about half and inch so that near the perimeter - when the marble is set down - the carpet can be tucked underneath the marble, which is set up a quarter inch.

Now, if that is good, does the carpet need any adhesive, or any tack strip, or would tucking it be enough? Since it’s alot like running into a baseboard, maybe it would be best to tuck it under the marble, but add a tack strip around the edge.

Or is all this the wrong approach?

As I am now suffering with puckery, stretched carpet, I’d vote for tack strips. Nothing is quite as sloppy looking as carpet that isn’t installed nice and tight.

Personally, I’d not raise it, but I tend to envision spills seeping into the least accessible spaces drawing insects or emitting odors.

Hmm, but it’d be raised no more than a baseboard. I think tack strips are smart though. I want a snug fit.

Don’t tuck it Phil! You will regret it. I don’t know about the foot traffic that will be present around your new hearth, but over time you will be tucking it back, and tucking it back, and tucking it back…Best to go to the local carpet store and but some prenailed concrete tack strips you can cut on your own…they come in a variety of colors and you can match it to a good hue that will go with the marble and the carpet. Go for the clam-shell if they stock it. This is a carpet tack on tuff plywood, with a designer “clam-shell” the usually comes in a silver or gold…used for joining carpeted areas to linoleum, stone, marble or any different textured surface…Got any pics?

Oh, you’re talking about the strips that catch the carpet from the bottom and close it on top, all of which is secured into the concrete - like a transition piece.

I was thinking of avoiding this look though. Do you really see that approach near hearths?

Pics? I was going to post some after the whole shebang was done, but I’ll see if I can get some posted somewhere. I promised some after staining the mantel.

See, this is my dilemma: Phlosphr’s idea would work, and it would be secure, but I just don’t see that near fireplace hearths…which led me to approach the problem a la’ when carpet meets a baseboard, with the regular tack strip underneath the carpet about an inch away from the baseboard, and the carpet tucked under the baseboard.

I see your point. Then in that case I would get some prenailed concrete carpet tack…not the folding kind, the wood with predrilled nails. Bring the carpet to the the edge of the marble and fold it under the tack, then nail down into concrete. This will give the appearence of the carpet coming right up to the marble and melding into it. However, if you want to try your base board idea, you must remember there will be a bit of a lip. I’m assuming you have standard grade inch thick marble. I’ve seen several wood variations to the clamshell tack that look very nice. And come to think of it, I am not sure how our hearth meets the carpet…we have a modern cobble hearth with flagstone inlays…and the carpet just comes right up to it. it’s probably a layover…

Hmmm…considering the suggestion to fold under the strip.

I’ll test that out.

About the lip: I was going to create a lip by setting the marble slab on a 1/4 " backer, but also keep the backer 1’4 shorter all around. So that it looks like this from the side, with the x’s as the marble and the ='s as the backer.

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