Concrete Floor: Float or Trowel?

[Wild Weasel]

I'm all ready to pour concrete into the shower I've been "building" for a year and a half now... so I go to HD to pick up the flat doo-dad to spread it out and smooth it over.

I'm expecting to go in and buy a metal thing and come home with it, but when I get there, it's not so simple.

I know the advice I got here was to use a float. Several different sizes, as I recall.

I didn't realize though, that a float isn't the same thing as a trowel. As labeled, the float is a tool with a sort of spongy foam pad attached to it while a finishing trowel is what I thought I was going to buy.

I bought neither, figuring you guys will set me straight. :) Do I need the spongy thing? What makes it better than the trowel?

I ended up just getting the metal mesh and some aviation snips to cut it with.

[drtyhands]

U need both.Float pushes agregate down and raises the "cream",let cure till it sets up enough to finish trowel.

[drtyhands]

1.screet to level
2.tamp agregate down
3.float Magnesium or wood to raise "cream".
4.Let set up
5.finish trowel.

[plumberscrack]

I only use a float to spread grout...can it be used for concrete too?

I use a wooden trowel to "raise the cream" and a metal one to finish it off

[Wild Weasel]

Thanks guy! This thread just made it blatently obvious that I gotta go do more research. I figured I'd mix some water in, scoop it into the shower, spread it around and then smooth it into the shape I want.

Looks like there's more to it than that. :)

Screet? Tamp? Cream? :D

I'll get both tools and do some reading.

[BHD]

the foam float is for pushing grout into a tile floor, or another way of saying it, to fill between the tiles full of grout,

there are also other "floats" some make of wood, magnesium, aluminum even a resin filled canvas, these are "hard" but there not entirely "smooth" they lightly drag the cement and in the process, and what they are used for (concrete settles or shrinks as it sets), and you end up pushing the rocks down and in the process the top of the surface has cement and sand in it, (cream), and as it sets the rocks will appear again and it will need to be "floated" again, I like the magnesium float. (a wood float is fairly aggressive, but if one needs to save some money one can make one,) this process may need to be done a number of times, (if you use a trowel it may seal the surface and the top may pop, or flake off in time to come,)

As it sets it will get firmer to the point that it will be hard to push the float into the surface, that is when the trowel is started to be used, you use in the same manner as the float, more weight on the heal of the trowel and with a slight tilt in the direction of travel, working usually in a fan pattern, and as it continues to set, you can work it so it is as slick as glass, if one wants.

If your going to tile it, then you may only need the float, as a slightly rough surface to set the tile on. if no tile then the decision is how slick you want a shower floor (as a wet floor is can be slick), it may take up to 3 to 6 hrs for the cement to set depending on richness, heat, and type of concrete. (trowels, the normal cement trowel is about 3" by 12" to 18", and has a very light bow up wards, towards the handle, the dry wall trowel is about 4"x 12" to 14" and has a bow down ward away from handle, and you will not be able to finish cement with one as it will leave lines in it all over the place,
there is what is called a pool trowel as well for curved surfaces, and the corners are rounded, and can make a curved surface easier to work, as there is little edge to leave lines in the surface.

[Wild Weasel]

Yeah, I know about them for doing grout. I just didn't know why I'd need one for pouring thin concrete (preslope) floor.

[YankeeConCo]

Yeah, I know about them for doing grout. I just didn't know why I'd need one for pouring thin concrete (preslope) floor.

The Foam in the float will help draw moisture FROM the concrete, which will make the "cream rise", and provide a somewhat smooth surface until it has set enough to do a "finish" glaze with a Magnesium or steel float. the whole idea is to get it smooth. When you do the "finish" coat is when you actually start working your slope in.

[thedcdude]

You say you're making a shower pan? I've always used type "S" masonry cement, not concrete for this.

[papadan]

A scrap of 2x4 will make a nice float for your application of one little shower.:D

[Pipestone Kid]

You didn't say, but I assume that you are going to be putting ceramic tile over the concrete. If I am right, papadan is right on--you don't need floats or trowels to do the job you are doing.
Jim

[Wild Weasel]

Yeah, this is only the preslope. Over this will be the liner, then more concrete, and then tile.

So I just spread it out with some wood, then smooth it over with the trowel in the slope I want? No need for floats?

[garager]

Well since this was only mentioned about 6 times, I might as well put my thought into it also, lets see, no need for a float, use a 2" x 4", cut to a proper length.

[Wild Weasel]

drtyhands man... you just trying to scare me? :)

[MudIsFun]

You do not mention if your hot mopping this or doing an epoxy pan liner. If your having this hot mopped then you may not need to do the pre-slope. My hot mopper always did this as part of the hot mop install. After the pan liner is in we usually dry packed the pan with moist cement which is easier to deal with and dries rock hard.

Good Luck

[Mr. Concrete]

Yeah, this is only the preslope. Over this will be the liner, then more concrete, and then tile.

So I just spread it out with some wood, then smooth it over with the trowel in the slope I want? No need for floats?

Just my two cents,
use a 2x4 to rod (screed) it off, then a hand "mag" flaot to close it up.

[drtyhands]

drtyhands man... you just trying to scare me? :)
I did post before I understood that all you were doing was floating for slope.Terminology in the quick view of your original threw me.Is this existing slab on grade? If so MrConcrete's 2x4 and wood float will be fine.Just now saw your question.

[Wild Weasel]

Yeah, this is being put on a level piece of plywood.

I built blocking walls all around so essentially I have a wooden box with a drain in it. Then I cut some vapour barrier plastic to the shape of the bottom and stapled it down so the concrete won't sit directly on the wood. Then I cut a piece of steel mesh the size of the bottom, cut out a hole where the drain is, and stapled that down as well. Now I'm ready to put the concrete in and make the 1/4" per foot from the drain sloped floor.

After that, I've got an Oatey shower liner to put down and clamp at the drain and then will make another concrete floor on top of that which is what will end up tiled.

[drtyhands]

Sounds good W/W.You picked up on the reference to vapor barrier on plywood.I've seen jacuzzi tubs lift after mortar base warped plywood.

On the drain,hopefully they gave you the two piece drain so you can sandwich the membrane between the two pieces.

Your doing great.Oh yeah,nice blocking up the wall to provide backing for the membrane;)

[Wild Weasel]

Yeah, I put the two piece drain in myself. Same was what used to be there... but the old one broke when I tried to take the screws out of it. I ended up having to cut it off below the floor, then put a coupler down there, then put the new one on. It was pretty annoying. :) I think I posted about it here a few months back.

The blocking goes up about a foot and a half or so to support the liner. That's something that wasn't there at all before. the old liner was just nailed to the studs and drooping between them.

I'll try to remember to take a pic tonight showing where I'm at with this. Looks a whole lot different than it did a year and and 2 months ago when I started. :D

[Wild Weasel]

Here's the pic I posted here in December of last year. :D

http://www.wildweasel.ca/images/construction/20061230/shower.jpg

[drtyhands]

Your drain looks like one that has three parts,the bottom flange,top flange and then the ajustable grate riser that screws into the top flange.I have not used these before as most of our pans are hot mop tar and the hot mopping contractor won't warranty anything but a cast iron top flange.Does your drain have the weep holes? Sorry,don't mean to appear to be making a mountain out of a molehill.Just trying to cover all your bases and I don't work with Bichuthane membrane.Lot of it in the industry though.

[Wild Weasel]

Don't be sorry! More information is WAY better than not enough! :)

I think I've worked out all the stuff I need to do. It's just a matter of figuring out how to do it now, such as how to actually mix/pour/form the concrete.


Remember... that pic is of the old stuff, though the new drain I replaced it with is exactly the same.

The drain is as you say. There's 3 pieces. The bottom is permanently attached to the pipe. The flange bolts onto it and has weep holes, and finally the middle part screws in and can be adjusted to whatever height it needs to be.

Of course, the weep holes are where the bolts are so the water would have to be a quarter inch high before it will make its way to them. I guess that's normal though. No way around it as it has to be solidly clamped to the liner.

[Wild Weasel]

For whoever's interested, here's what it looks like now.

http://www.wildweasel.ca/images/construction/20071107/shower_1.jpg http://www.wildweasel.ca/images/construction/20071107/shower_2.jpg

The pipe has a cap on it so I could test my joints. I've just drilled a hole in it to let the water out so I can remove the cap.

In retrospect, I wish I'd just put a valve on it but I didn't feel like spending the few extra bucks on the valve over the cap.

Would have saved me having the water shoot at me when I drilled through it. :D

[humbletile]

Hey WW,

Sorry I just skimmed over the thread and I haven't seen mention of using "mud" not concrete. "Mud" is what we call sand mix mortar that is mixed just wet enough that you can pack it in your hand. That is the only way you are going shape a slope. I use a finish trowel to pack a cut the mud into my slope. I finish with a 2x4 or a piece of tile no bigger that 6.x6 and I make circular motions around the slope. This will allow you to feel any high spots. Also I know this is your pre-mud but this is good practice before you have to do it real. Hope this helps.