Exposing Concrete Floor

[deanhendry]

My girlfriend and I just got into our "new" 1957 house. Before we actually move in, we're re-doing the floors. There is carpet and linoleum throughout, but we are going to expose the concrete floors. We got all of the carpet out yesterday and found what I'm guessing is original linoleum in one of the rooms. I've heard bad things about getting the glue up off of the floors. Some people have suggested sanding the floors. Some people have said if I do, the house will be unliveable, due to the release of asbestos or whatever chemicals are in the glue. Has anyone gone through this process that might have a few suggestions on how can get this done safely?

Also, I have heard that when I pull up the tack strip from the carpet, we'll get a bunch of pits in the concrete. Because of this, I'm chiseling out the tack strip and getting all the wood off of the nails. I'm planning on using my dremel to cut the nails off at the level of the slab, so we won't have a bunch of fill to do later. Does this make sense?

The last item is about cracks in the concrete. The slab is in really good shape for the most part. There are only a couple of cracks and none of them are very big. I've been told that I will need to use wood putty to fill any pits/cracks. Is that right?

Any help is very appreciated.

Thanks!

[KARLITO]

Wood putty?! No that is not right. Sounds like you have some work ahead of you. Is the "linolium" in 9"x9" tiles? Or is it a sheet? If it's the 9x9's you can bet it's asbestos, which really isnt that big a deal. Prolonged exposure to massive quantities is whats bad for you. Just wear a mask. So once you get the tile demoed. You will still be left with black mastic (glue) that held it down. This will need to be stripped w/ a floor machine set up with a black pad and you will have to use a chemical stripper. Just open all the windows & wear a respirator. During & after this stripping you will need to mop about 1000 times. Then stain and seal... It's a pretty big job. As for trying to carefully pull up the tack strips so you dont have holes, good luck with that... Easier to just rip 'em up and patch the holes with a concrete patch product. Chances are you will have some other stuff to patch anyway. Even after all this your floors will not look brand new. You will of course see any patching & cracks as well as a ghosting patern from the tiles. All in all it is a beautifull floor if you like stuff with patina.

[Nginear]

Congrats on the new house. My wife and I bought a "new" 1958 home a few years ago and went through the same thing.

While patching the chips in the concrete from the tack strip, I was wishing I had tried cutting off the nails flush to the concrete first. My main concern was matching the color of the concrete. Our slab is colored light-brown-tan (original). Patching the holes was fairly easy, just mixed up some colors with the concrete-patch product and filled them in. Once the concrete dried, we ran a small orbital sander over the patches to smooth them out. Knee pads help make this easier!

Ace Hardware sells a crack filler. Fill the crack, let it dry (it shrinks a little when it dries) then top it off, let dry then sand it level. Use the paint on top to match the color.

As for the linoleum tiles, we had it in the kitchen and two baths. The tiles came up easy and a long scraper took care of the little chips that stuck. The stripping agent for the mastic works well. Just need to pour it on, let it do its work for a while, then scrape it off (get a long pole style scraper with replaceable blades). You may need to repeat in some areas where the mastic is thicker. The fumes are strong, so keep the windows/doors open. Keep them closed if you want a free trip to magic-land to see the sourcerer and his purple unicorn.

It's a bit of work but it looks great and I love having concrete floors. Note: there will be some "shadows" left from the linoleum. I didn't seal the kitchen or bathrooms and over time, due to high traffic, the shadows slowly start to disappear.

Hope this helps,
-Brian

[deanhendry]

We have gotten all of the carpet and tack strip out except in the hallway and all I have to say is that the person who installed the tack strip is a real A-hole. There are parts of the house that they were putting nails 1" on center or less. There was one spot where there were six nails lined up head to head and another nail across the top of them into the door frame. It made for a long task, but we're almost done with that. The concrete under the carpet looks FANTASTIC!!! We are so excited.
There are 9x9 tiles that we found under some of the carpet and I tested the long floor scraper on them tonight. They pop right up. There is also a sheet material in the kitchen and one of the bathrooms. I tested pulling that up tonight and it looks like it's going to be a LONG day tomorrow. The long scraper didn't do anything. I used a smaller 4" scraper and that one wasn't really doing a whole lot either. Any ideas on what I can do to get that up quickly, or is this just something I'm going to have to do slowly?

[Nginear]

Sounds like the carpet installer got a little crazy with the nails...

As for the sheet material, is it similar to linoleum? My only thought is to use a long chisel and hammer, like the tool used to chip away tile.

I forgot to note that when you use the chemicals to remove the mastic, the floors will leach calcium leaving a white haze on top of the concrete. This is why KARLITO mentions mopping 1000 times. The concrete will leach for a few days or so.

When it comes time to seal the floors, use SEVERAL coats. I only put two coats down. The dogs, shoes and sliding furniture have won so it is time for me to re-seal again.

-Brian

[deanhendry]

It is a linoleum type product. I will try the chisel method. Thanks!!

[deanhendry]

We got all of the flooring up this weekend and got most of the black glue off. We just have to hit a couple of tough spots with an orbital sander (including all of the edges and corners) and the floors will be clean. I think chiseling out the tack strip helped. We didn't end up cutting off the nails though. It was too hard to get the nails flush with the concrete without damaging the concrete. Instead, we just tapped the nails lightly until they came out like a loose tooth. The pitting is all relatively minor. There are some areas that we'll need to patch due to previous removal of tack strip. They left some big pits and filled it with some white filler. It looks like drywall mud.
My one concern at this point is how to get at the underside of the overhang for our cabinets. The mastic goes all the way to the bottom of the cabinet which is unreachable with floor buffer or orbital. Is this an area that I will need to use a sanding block (or something like that) and do it by hand? Would an angle grinder work with the right grinding wheel, like a flimsy fine grit sandpaper?

[maynard7]

I'm going to be exposing concrete floors pretty soon myself. I've heard that you can have a contractor pour a skim coat of concrete over what's already there. Would that be easier overall, and if it's possible to do this, would it be expensive? I haven't asked for any quotes yet.

[genius]

maynard7 -

Right before we decided on the final flooring solution (cork) we had our concrete sub do an estimate for pouring 1/4" layer of Ardex (concrete leveling compound) over the existing concrete floors throughout our house. The total square footage to have been covered was around 1900 and he wrangled with one of the manufacturer's reps to come up with a pretty decent price for us - $4500.

Considering that when we started talking the cost was at nearly $5500 it was a considerably better deal than we were expecting. The only thing that got in the way was the major annoyance of having to move everything already in the house outside. Just couldn't get past that since I have close to three thousand books I've already had to move three times this year (a picky minor thing to most, but there it is.)

Anyway, we were told that the cost would generally run between $3.00-4.50/sq. foot. Ardex is available for purchase in Scottsdale over in the Airpark, I think on 78th or 79th Street. If I can find the name of the company and their address I will post it for you. Good luck.

[maynard7]

I will start studying up about Ardex. I just have a 950 sq ft condo and only want to re-do the concrete in the living room, kitchen & possibly the baths (bedrooms to be carpeted). Perhaps patching the holes from the carpet tack strips & then painting the floors would be a possibility for me as well. It surprises me that doing a skim coat would cost so much, but I've never looked into it before. Thanks for the Ardex tip!

Edit.... I'm shocked at how much Ardex costs. Even if I only have 450 sq ft coated, it would be nearly $1,000 just for the materials. I hope there is a cheaper alternative..... sounds like somebody's making a whole lot of money off Ardex.

[genius]

M7 -
That's part of the problem when a product is proprietary - they get to set the price and that's kind of where it stays. Ardex makes another
product that they sell to fix chips and nailholes. It's called Feather Finish. A 10lb. bag costs about $13-14 dollars and goes a long way. I'm using it now to fill in holes from tack strips and a few cracks here and there before we lay down the cork. It came form the same flooring supply company - Big D Supply. They're at 14305 N 79th St # A in Scottsdale and at 2802 W Virginia Ave in Phoenix. They guys in the Scottsdale store have all been really helpful and seem pretty knowledgeable about what works for different floors.

[maynard7]

Thanks for the tip on Big D Floor Covering Supplies.... I went to their location at 2802 W Virginia Ave and talked to Tom (the store manager). He recommended that I use a new product from Ardex called "CD Fine"... Concrete Dressing Fine. It will be about $660 for 500 sq ft, plus installation costs. He recommended John from Ameribroad as an installer; I talked to him on the phone and he was enthusiastic about the product. He's going to come out and look next week. One of my friends strongly recommended Tom at Farwest Supply, so will call him too on Monday. Hope it works out because I've always wanted that "loft look"

[Na]

Ardex is coming to the attention of homeowners who want "quality" results because, Ardex products were developed, formulated and brought to the COMMERCIAL market place to solve significant concrete problems on HUGE commercial jobs. A company that puts money into research, sales force and distribution to be specified on multi-million dollar construction products is not going to suddenly over night meet the price point of the average residential buyer. I've wanted Ardex to be inexpensive for years and its just not happening.

However, experienced installers know the quality and effectiveness of Ardex and its extensive line of products and so it is slowly coming into the awareness of saavy residential consumers who demand "excellence". My take is to view Ardex (which I've had positive experience with) as the "quality step and choice" to take to truly realize an optimal end result. In other words its the "upscale" choice of concrete finishing products. We pay more than we want but, the results will be excellent.

I've not used the new Ardex product mentioned abone but, I can vouch for the brand and its reliable performance.