Smoothing Concrete to install Tile - DIY Chatroom

DaveyCrocket · 10-18-2009, 06:13 PM

I have an older home that sits on a slab. Twenty years ago the previous owner put on an addition. I am going to put 12x12 tile in a bedroom. The old slab and new slab meet right in the entry way of this bedroom.

The joint between the two slabs looks like they tried to mud it with mortar and it is pretty rough. I could feel it when it was carpeted.

Can I somehow grind this down 1/4" or so, so it is smooth? Otherwise I would have to build up the thinset in that area,, which may require me to build it up in the entire room.

IS there a grinder that I can buy/rent that somebody in the past has had luck with?

Thanks in advance

rselectric1 · 10-18-2009, 06:17 PM

The flooring guru's on this site will probably ask you for photos.
You might want to post some.

I'm interested in what they will have to say about this.

oh'mike · 10-18-2009, 07:09 PM

Hi! To knock down a small seam ,when you aren't looking for a pretty job,try this---

Buy yourself an inexpensive 4" angle grinder.Next pick up a 4"diamond 'clipper' blade.
That's the one with notches ,designed to be run dry.

Just cut a series of shallow slits and knock off the offending concrete with a hammer and cold chisel.

It the same thing you would do to clear a notch in a 2x4 with a skillsaw and chisel.

It's going to be dusty!!!!-MIKE--

CookeCarpentry · 10-18-2009, 07:51 PM

Is it an elevation problem or it is just rough?

If elevation, what the guy before me said to do will work. You can also rent a concrete surfacer...grinder, but usually only for larger areas.

If it is just rough...no need to worry, the thinset will grab either way.

oh'mike · 10-18-2009, 08:55 PM

Cooke-Sounds like a high spot right at the door-Just needs to knock down a nasty hump.

Sounds do-able.

DaveyCrocket · 10-18-2009, 09:59 PM

Thankgs guys, I will try the grinder/chisel idea.