DIY Home Improvement, Remodeling & Repair Forum > DIY Home Improvement > Framing and Foundation > The use of river rock and broken concrete bits

Thread Tools Search this Thread Display Modes
Old 11-24-2010, 01:10 PM  
Junior Member
Join Date: Nov 2010
Location: Los Angeles, CA
Posts: 26
Default The use of river rock and broken concrete bits

as filler to reduce the concrete volume needed, I mean.

I am talking about a slab floor construction common or standard in Southern Cal newer homes, not concrete foundation with floor joists.

There are a lot of give away broken concrete pieces and river rock. Can I use them to fill the concrete slab?

My thinking is that it is OK as long as the pieces and river rock are small, say 3" thick and 4-5" in other dimensions, or smaller, and using them in the middle non-weight bearing section of the slab.

The weight bearing sections (perimeter) of the concrete slab will not have such filler.

Any opinion. I found it hard to believe that such filler will "sink" later once the slab has cured.

Also I plan to add such (the smallest) pieces 3" or smaller into the cement mixer and not just pour concrete mix over the filler pieces. I think this way the fillers with adhere to the concrete better. Will the mixer take it without falling apart? Mine is a small 3.25 cu feet mixer.


HighDesertHomeOwner is offline  
Reply With Quote
Old 11-24-2010, 03:15 PM  
Senior Member
granite-girl's Avatar
Join Date: Oct 2009
Posts: 204

Kinda sounds cool. What kind of area are you talking about & how big ? Pictures would be great when you are finished..... that is if the powers that be on here say it can be done.
Good Luck


granite-girl is offline  
Reply With Quote
Old 11-24-2010, 07:10 PM  
inspectorD's Avatar
Join Date: Dec 2005
Location: Litchfield, CT
Posts: 4,271
Liked 187 Times on 156 Posts
Likes Given: 477

Default ok

I would suggest trying a "test Patio" before you do it. Usually anything up to 3 inches is the limit for aggreagate size, it all depends on your mixture. The stuff from the yards (professional) has 3/4 rock unless you specifiy different.
Try for a mix that is able to be built into a baseball type consistency, this tends to have less water and more portland mix. This should create a higher strenth PSI concrete. The reason is you want to be over 2500, but with a mixer this is hard to guage if you have not done this before.

These are some concrete folks around, they may chime in too, just my
Just My
Made in the
inspectorD is offline  
Reply With Quote
Old 11-27-2010, 06:52 AM  
Senior Member
Join Date: Sep 2009
Location: hilton head & atl, sc & ga
Posts: 287
Liked 1 Times on 1 Posts


don't be a cheapskate,,, by the time you hustle about finding broken conc you'll have wasted more time, gas, & vehicle wear & tear than you've saved,,, river stone's smooth - not a good candidate for inclusion into conc UNLESS you're 'seeding' it into the top for a decorative effect.

its impossible to duplicate the quality of conc from anyone's redi-mix plant so why anyone needs to mix their own mud's usually beyond me but understand economics of small deliveries from plants.
itsreallyconc is offline  
Reply With Quote

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

Similar Threads
Thread Thread Starter DIY Home Repair Forum Replies Last Post
weak hammer drill, bad bits, or ? Dave928 Bricks, Masonry and Concrete 13 06-26-2010 11:13 PM
River rock bed Bruce T. General Home Improvement Discussion 1 01-27-2010 09:40 AM
Repairing one broken concrete step Perry4124 Bricks, Masonry and Concrete 2 08-17-2009 11:30 AM
Bad Pour on River Rock Patio KHO Bricks, Masonry and Concrete 3 08-14-2009 03:51 PM
River rock around house. Mudball General Home Improvement Discussion 2 06-16-2006 04:29 PM

Newest Threads