Pond pebbles instead of crushed gravel for the driveway – what to do?
Hello,
Our general contractor received a wrong kind of gravel for our big driveway install. We have 1500 sf to build and 1/2 of it is a concrete driveway and 1/2 permeable pavers. We have 2/3 of the total rock needed already on site. And that rock is pond pebble instead of limestone gravel that would have properly compacted under the driveway. Supposedly this cannot be returned. What are we to do?
The contractor says to use it in the permeable section, where it would lay on the sheet of geotextile fabric. We still have a rain water dry well to build on the front of the property, but that would only take a fraction of this rock…
Please help,
thanks,
Lucy
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Replies
Where are you located? What materials are available nearby from pits or quarries? How much material are you talking about? Looks like two truckload in that picture perhaps which may amount to 40 yards or so... please provide more info.
Lucy- someone screwed up and it wasn't you. Either the contractor ordered the wrong gravel or the supplier delivered the wrong gravel. If you don't have any use for it, one or the other of them should pay to remove it. Of course, if you can use it somewhere, you should do so.
I agree with Stephen. Plus these are not the right stones for your application. Pond pebbles are round and smooth so they don't interlock or compact well. If you put those under the permeable pavers in the driveway, they will move under the pressure of the cars and you will end up with ruts. You want clean crushed stone that has sharp edges which interlock when they are compacted.
Where I'm from these pebbles are $50/ton, whereas crushed limestone is $6/ton. If the price differential is similar, I'm sure you could quite easily sell the stuff.
Where I am from the price is about the same, but I had a question I was going to pose to her regarding whether she needs to build up the grade at all. More details might be nice but essentially what I would suggest to someone in this situation is to get "bank run" IF there is a supply nearby and mix this product with the run of the bank (which already has this type of aggregate in it) to build up the grade and yo provide a good draining sub base. First geofabric should be put down, then the "bank run" and then the crushed stone and stone duct blend that is the product of the crusher, which in New York is called "crusher run." Depending on how durable a driveway one wants to create, the addition of such aggregate to the silty, fine gravelly sand and people mix that comes from the stream banks as sub base one can create a system that will last as long as s super highway if they know how high they can build up their driveway. But that is assuming someone doesn't own up to the mistake and supply the correct stuff. Actually even IF someone DOES own up to the mistake, it is unlikely they will come and load the material back up, but they will just let the customer keep it to do what they see fit with it, and send the correct stone as make-good product. Hence my suggestion she order some bank run to mix with this washed stone to build up the sub base. If you remove some native soil and place this in the sub base, with the ROB you can use it that way.
Lucy,
I agree that this is your contractor's problem, not your problem. This type of stone may not work for a driveway, but it would be a good material to use to backfill around a foundation -- providing great drainage.
Unfortunately for your contractor, who clearly has a headache, the cost of the material is irrelevant. Most of the cost associated with this type of material is in the trucking, not the material cost. Trucking it twice is no fun.
Thank you everybody for comments. In our area, the price of either stone appears to be similar to the other, like $35 vs $34. We already have limestone backfilling around the foundation, so Martin's suggestion won't work for us. Joe, thank you for the suggestion how to use this stone. We may be able to use a portion of the stone to buildup the base, like 2'' or so. We only have 8-10'' total for fitting the base and concrete or pavers. I presume that the crusher run is used under concrete, but not under the permeable pavers..? I also wanted to understand if one would put the geotextile fabric after the base of bank run with pebbles is laid, (not below it), to separate other rock that is to remain clean. That clean rock would provide water storage capacity (before water dissipates through sub-base, etc.)
I also saw some products like DuPont GroundGrid Ground Stabilization Small Grid (4' x 25')
SKU: DPGG-5055 Product Weight 11.00 Pounds
This honeycomb grid geotextile is a 3-D system for soil stabilization. Simply fill the grid with gravel, rock, sand or loam. Cell dimensions: 50 mm x 55 mm. 2 inches deep, for $199. If we used it to use the pebble rocks under pavers, it would add $1400, not so little...
Depending in the native soil conditions, you can out the fabric either under the bank run/gravel or between the bank run/gravel and crusher run, or stone dust or whatever base aggregate you intend to use under those pavers. If you have the budget put two layers of fabric. One on the ground with the bank run over it and then one above that before the crusher run. Most would say that is overkill but it all depends on how nice you want your drive way to be and hold up. I have a varying driveway where the first 150 feet is over clay and then runs into an area where I have loamy yellow sand. I guess it is just how the glaciers left it. Nonetheless where I have clay, I have two layers of fabric. Where I have sand, I simply have the fabric, then the bank run and then #3 crushed gravel with a thick layer of crusher run and stone duct making about a 14-16" thick driveway. I think I have a kiloton driveway now, because between the three aggregates I have 1,000 tons of material on it. I figure on 200 more cubic yards of crusher run/heavy on the dust to shim it up and level it once construction is done. The nice thing about the geofabric is that you won't lose your material, and it all stays there without sinking into the mire.
Geotextile, Lucy- is a lot less than the product you are mentioning. I can't believe that gravel costs 34 bucks a ton where you live! Wow! I paid about $9 per cubic yard for bank run delivered and $12.25 a ton for the crusher run delivered so my kiloton is only maybe $11,000. Where is it that you are? Also, last thing- get a good excavator to do your driveway with vibratory roller for compaction. Someone with some expertise to guide you. With that kind of price on material you certainly don't want to waste money and the fabric should be a bargain in relation to the material since when you use such fabric you can always get away with less on the way of materials.