[mystreba]

I live between Balt. Md and Wash. DC, Zone 7. I have three tons of field-stone that I had originally purchased to cover a brick hip veneer on one side of my home, then decided to use master-cut veneer due to concerns over adding three tons to my foundation. Now, I want to use that field-stone to construct a free-standing block/veneer wall.

I have seen many of these walls being constructed at the entry points of new neighborhoods going up in the area. They typically construct a cinder block wall, scratch coat it, then apply a field-stone veneer. This is the approach I want to take.

My question concerns foundation. I've seen these walls constructed as follows:

- dig a trench a couple feet deep
- drive rebar into the ground along the trench
- pour a layer of gravel along the bottom of the trench
- construct the cinder block wall on the gravel bed, with the rebar sticking up through the holes
- mortar in masonry ties as you go
- fill the block holes with mortar as you go
- when complete, scratch-coat the entire thing

The end result is a near-solid block wall reinforced by rebar and mortar, but built on a foundation of gravel.

Does this work? I'd always imagined I'd have to pour concrete footers and slab, etc.

thanks...

[Lanelle]

I'm near by you and that isn't the the method that we use or that I've seen used by experienced stone masons. There should be a concrete footer poured, preferably 8-10" thick, with the bottom at two feet deep. Lay up the cinderblock and proceed as you described. The footer should have rebar in it also. With the clay that we have, a gravel footer will move enough to crack mortar.

[mystreba]

Does the footer have to be poured on top of a gravel bed, or can it be poured directly into the forms? If gravel, how deep?

How much should the footer "overhang" the actual structure?

thanks again...

[Lanelle]

Since this will be a free-standing structure and not a retaining wall, your footer can be a bit narrower than for a retaining wall. We would have the footer be 24" wide for a 12" wide wall.

[mystreba]

I really appreciate your answer, but can't tell whether you're suggesting I pour the footer 24" wide for a 12" wide wall (double the width), or narrower than that. I think I'll go with double to be safe. Since my wall will be single-block wide (8"), I'll pour a 16" footer. After attaching the field-stone veneer, that should make for a 12" wide wall, with 2" of footer "overhang" on either side.

The wall will be approx. 6 feet tall. Please - if my dimensions are off, either structurally or aesthetically, let me know!

Also, I'm still unclear whether I need to fill my trench with gravel (and if so, how much) before I pour the concrete for the footer.

thanks again...

[Lanelle]

Gravel under the footer is good-about 3-4". For your project, the footer should be 24" wide since the stone with block will be 12". That will give the wall more of a 'toe' on each side to prevent it from tipping. Also, backfill with clean gravel up to your planting depth. You are trying to prevent freeze-thaw action from affecting the wall.

[mystreba]

Thanks, Lanelle. Great website, by the way. You guys obviously do good work.

I'm sorry I've been dropping questions in dribs and drabs. I finally realized I needed to get it all down on paper and ask all my questions at once. duh. So I'm closing this thread to open another, more comprehensive one. Hope that doesn't break protocol.

thanks again...