Granite scraps in foundation, floor or walls?

Hey Everyone,

I know that this is an bass ackwards way of approaching building decisions but I have to give it a shot....

I am kicking around ideas for building a small outbuilding (200sf or so) as an office/workshop. I am considering a rubble trench foundation, cordwood walls and a roofing material that will accommodate rainwater collection.

My question is: How can I utilize a significant supply of free granite scraps in this project?

I have about 2000lbs of scraps that range from 2"x6" to 24"x24" and I can pick up 2-3 pallet loads a week from the granite fabricator down the road.

I have considered taking a sledge hammer to it and breaking it up for use in the rubble trench but am concerned that the polished side could be troublesome?

With a wet saw I could manage a random granite tile floor or wall covering. I am not too sure I want a polished granite floor though.

I am laughing at myself as I post this... I drive by the granite shop almost every day and see pallets of granite sitting there and have to fight the temptation to stop and pick up another pallet....

Any thoughts as to a sensible application of this free resource?

Thanks.

S.

I'd lay them in mortar like bricks. I don't think the polish on one side will ruin anything. After all, gravity holds it together, not mortar.

But I haven't done it.

Seriously can't wait to see pictures. I wouldn't be able to resist a resource like that either.

Mike Cantrell wrote:I'd lay them in mortar like bricks. I don't think the polish on one side will ruin anything. After all, gravity holds it together, not mortar.

But I haven't done it.

Seriously can't wait to see pictures. I wouldn't be able to resist a resource like that either.

If I use them for wall covering or countertop I would likely cut them into common widths & random lengths and do something resembling subway tile set in mortar.

The concern about the shiny side in the rubble trench where there will not be mortar and I am concerned that they may not interlock the way typical rubble will.

Also, for flooring, I am not sure that I want a slick surface. Could be quite slippery when wet.

I just had a random thought:

I wonder how it would play if I were to cut the granite into a usable size/shape and then load them into a cement mixer with coarse sand. Let it run for a while to break the sharp edges and rough up the face a bit.

Any thoughts?

It wouldn't really work to rough up the polished side, even being tumbled against other stones, you'd probably burn out the motor first.
You'd be better off just taking something like a disc grinder to score the finished side, or a belt grinder/sander to take off the polished finish.
Using it as flooring might make sense in that it's free, but it's not really appropriate, and can lead to heating issues.
I'd use it to make a foundation wall tho, laid out brick like, to make one of those bottom-stone, top wood facades. You could bring the stone up as far as the window sill height, and then continue the rest of the way up with cordwood.
But if you can get enough of the large sizes, why bother with the cordwood at all? Besides the labour.

As for rain catchment on your roof, just about anything would work for that. What's the key would be the gutter system that you put up. Tho using a smooth metal or plastic surface would be recommended, instead of a asphalt or cedar shake roof, etc.

These are countertop scraps? About 1" to 2" thick? Unless you are in a seismic zone where the interlocking of rubble in the foundation is critical, I don't think it will impede use at least in the underground portion. But if you are considering roof tiles, it sounds like using the larger scraps for that would give a roof that would last centuries, as long as the structure can support it. How rough are the unpolished faces? Sandpaper, or ridged/bumpy?

It is countertop material and the back surface ranges from comparable to 80 grit sandpaper to epoxy/mesh covered.

I don't intend to use them for roofing. I have used a standing seam metal roof on my other structures and will likely do the same here. I would prefer cedar but I need the water to be suitable for household use.

As far a using it stacked flat for a wall, I would be concerned that it would conduct heat too well. The cordwood is a fairly good insulator.