View Full Version : BUilding a wall on top of a small existing foundation?

09-07-2008, 12:03 AM
We have to replace 4 small retaining walls that are currently brick. They go down about 8-10" into the soil where they meet a cinderblock foundation 36" deep (below frost).

Would it be ok to just put the new retaining walls on top of this existing foundation? The current walls are about 30-40 years old and are being replaced because they are leaning forward, but there is no settlement int he wall at all.


09-07-2008, 11:07 AM
I've done this once, it was at a buddies house, he had an old RR tie wall built on top of a footing, we took it down, cut a grove in the footing as we were using grinnell garbage block and they have a lip on the back and up we went, worked really well........that said it was a tie wall and it was only set on top of the footing, there was nothing really tying it together other than a couple pieces of rebar. In a block and mortar application I'd think it would all be tied in together better and therefore be more likely that the footing is leaning too. If I were in your shoes, I'd excavate along the back of the footing, thi will give you a chance to inspect it all and you'd be doing it anyway to address drainage, since you can't lay pipe on soil anyway' I mean you'll dig alot deeper that if you were just addressing drainage but compact it well and call it a day. I'd hate to build a wall on existing footing and get up a couple feet to find it's leaning.

09-07-2008, 01:44 PM
rip the footing out. charge extra for it. you cant build on top of a concrete footing. i highly doubt that it would be perfectly level and you need a good base of gravel that acts as a drain or do like what forestfireguy said dig behind it if you dont wanna rip it out and haul off.

09-07-2008, 02:34 PM
We have built on concrete and concrete blocks before, of course added gravel and built on it then.

09-07-2008, 09:45 PM
Thanks guys, I was going to excavate around the block to check it out, then do the regular stone fill since the blocks would need to be filled anyway. Then I could level that out. I will need to tear it up and inspect.