Problem Concrete Slab? - Concrete, Stone & Masonry - DIY Chatroom Home Improvement Forum

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Concrete, Stone & Masonry


Thread Tools Search this Thread
Display Modes
Old 03-26-2014, 08:20 PM   #1
Join Date: Dec 2008
Location: Western Arkansas
Posts: 323
Rewards Points: 250

problem concrete slab?

A 16X11 slab was poured in my sunroom a couple of months ago and replaced an existing broken up slab that was cut around the parameter about 6 inches from the wall and removed. New concrete was then poured into the removed area to the height of the remaining parameter. My wife who was home overheard the workers mention that the concrete was wet. In any event it looks okay and I'm getting ready to tile. But the top of the concrete remains "dusty" which I understand from reading here that that is a sign of too wet concrete. There are no cracks and I know they used rebar to tie in to the old concrete and put in wire mesh part way through the pour. Is this a suitable surface for tile or should I use some kind of sealer before tiling. Thanks
Mike in Arkansas is offline   Reply With Quote
Sponsored Links
Old 03-26-2014, 09:47 PM   #2
Msradell's Avatar
Join Date: Sep 2011
Location: Louisville Kentucky
Posts: 2,900
Rewards Points: 1,094

If you use a sealer the thin set you use for setting the tile won't be able to attach firmly to the tile. Your best bet would probably be to just watch the surface of the concrete, maybe even using a mild muriatic acid solution (be sure to neutralize it). After this let it set for a week or so to make sure it's completely dry.
Msradell is offline   Reply With Quote
Sponsored Links
Old 03-28-2014, 11:17 AM   #3
Join Date: Jun 2009
Location: atl & hilton head
Posts: 6,574
Rewards Points: 3,432

too wet means too much mix water = too much bleed water on the surface = dusty weak concrete surface,,, you'll likely need some major prep work prior to tiling - perhaps even a scarifier,,, tile won't stick long to a weak surface
stadry is online now   Reply With Quote
Sponsored Links

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Joining new concrete slab to old concrete slab homeless Concrete, Stone & Masonry 5 02-06-2014 10:36 AM
Need Help Fixing Damp Slab Problem in Shop OlyTDI Building & Construction 10 10-30-2011 12:35 AM
Supporting Concrete Slab from Underneath? Yippydadada Building & Construction 5 10-18-2011 04:24 AM
Waterproofing under wall on concrete slab JustADoc Carpentry 2 07-18-2011 06:20 AM
Filling hole in carport (concrete slab) chaddihimself Building & Construction 2 08-10-2007 12:50 PM

Top of Page | View New Posts