Gravel Delivery FAQ for Tidewater, Piedmont and Valley Jobs

Ground in this state does not behave the same way twice. Sand and silt with water sitting close to the surface east of the Fall Line, clay that sheds a thunderstorm straight off it through the Piedmont, limestone with rock near grade and sinkholes west of the Blue Ridge: each of those pushes a gravel delivery order in a different direction. The questions below start with the ones people get wrong before they order and end with the ones that come up once the material is on the ground.

Yardage, VDOT names and the Virginia building year

One cubic yard of #57 stone covers how much ground at the depth I need?

A cubic yard is 27 cubic feet, so divide 27 by the depth in feet: at 3 inches that is 108 square feet, which is the one figure worth carrying in your head. It is the same for any material, because coverage is a volume question and only the weight changes with the product. The calculators will run any other depth and give the tonnage with it.

A plan sheet says VDOT 21A, Type I. What is that telling a buyer?

Base material here is specified by the VDOT Road and Bridge Specifications. Section 208 covers the dense-graded sizes 21A, 21B and 22, each described as Type I, which is crushed material only, or Type II, which may include uncrushed material. Those designations are how aggregate is named on plans and at yards across the state. The product listings give size, grading and type; if a spec sheet calls for a particular type, send it through contact before ordering rather than assuming.

When in the Virginia year does clay, frost or storm season stop this work?

Base and driveway work runs through most of the year here. What holds it up is saturated clay after a long wet spell, frozen ground in the mountains in midwinter, and the late summer into fall storm season along the coast. A base rolled into ground that is still holding water has to be built twice, so the useful question is not the month but whether there has been a dry run behind the date.

The point where a professional takes over

Which Virginia jobs need an engineer or the locality before stone is chosen?

A retaining wall above a modest height, anything armoring a tidal shoreline, a new entrance onto a public road, stormwater work on a building site, and any excavation near a sinkhole in the karst country west of the Blue Ridge. Your own city or county sets the frost depth and the permit rules that apply, and independent cities such as Richmond, Roanoke and Fairfax are administered separately from the counties that share their names.

Two gray piles and three brown ones

Two gray piles, both crushed: which one drains and which one locks up?

Squeeze a handful. If gray dust clings to the pieces and the handful holds together, that is a dense-graded material with its fines in it: 21A, 21B or Screenings. It packs hard and it does not drain. If it runs clean through your fingers, that is a washed size such as #57 Stone or #8 Crushed Stone, which keeps its voids and will never compact. Putting the fines-bearing one in a French drain is the most common expensive mistake on a clay lot.

Can fill dirt, topsoil and garden soil be swapped around on a Piedmont lot?

No, and the weights show why they are not the same product. Fill Dirt runs about 2,400 lb per cubic yard and is there to build grade up under something else. Screened Top Soil is about 2,200 lb and belongs in the upper few inches where seed roots, which matters over red Piedmont clay that nothing will grow in unaided. Garden Soil is nearer 2,000 lb, blended with compost for raised beds. Fill under, topsoil over, garden soil in the box.

Valley against Tidewater, and what goes under the stone

Does a Shenandoah Valley lot want different stone from a Hampton Roads lot?

They pull in opposite directions. On the limestone valley floors, rock often sits close to the surface and water goes down into it rather than across it, so the work is about spreading runoff out instead of channeling it toward a sinkhole, and coarse material such as #4 Crushed Stone earns its place. On flat, low Coastal Plain ground with water near the surface, the work is about lifting the pad clear with fill and giving water a route out through washed stone.

Does landscape fabric belong under 21A, under riprap, or under neither?

Fabric is a separation and filter question rather than a material question. It is commonly used between a soft subgrade and a stone layer so the two do not mix, and under armor stone on a bank where a filter layer is part of the design. On firm ground under a base it is often left out. It is not a catalogue item here either, so source it from a local landscape supplier rather than adding it to this order. Where the work is holding a bank, a wall or a tidal shoreline, the fabric decision belongs with whoever specified the structure.

Rounding, a turnaround that loops, a bed that curves along a fence and the lane arithmetic are what the calculators are for. The drop spot, the checkout fields and sending a load to a client's address rather than a billing one are all on the delivery page.

Who operates Virginia Rock Supply?