3/4" Crushed Stone in Virginia: Where It Beats a Packing Base

Most buyers reach this page from the same starting point: a lane, a pad or a low corner sitting on ground that will not let water go. Across the Piedmont that is clay which sheds a thunderstorm in minutes and then holds what soaked in for days. Down on the flat Coastal Plain around Hampton Roads and the river necks, water is already near the surface before any rain falls. 3/4" crushed stone answers the water half of that problem well, and the load-carrying half badly, and telling those apart is the whole of the buying decision.

Ranked against 21A, screenings and drain rock

The other name to sort out is #57 Stone. Many Virginia yards use "3/4 inch stone" loosely for it, and the two are listed and sold separately here. If a drawing calls out a VDOT size number, order the number. If it just says three-quarter inch clean, either is generally what the writer had in mind, but ask rather than assume when the layer is part of an engineered build.

What 3/4" crushed stone does on clay, on Tidewater sand and near rock

• Piedmont clay. The stone stays open while the clay around it does not, which is exactly why it works as a drainage layer and exactly why it has to be separated from the clay. Without a separation layer, fines migrate into the voids and the layer stops draining within a few seasons.
• Coastal Plain sand and low ground. Around Hampton Roads, the Eastern Shore, the Northern Neck and the Middle Peninsula, the water table is close. Open stone tipped onto saturated ground gets pressed down into it, so excavation and separation are not optional there.
• The valleys west of the Blue Ridge. Where limestone sits near the surface, water in this ground goes down into the rock rather than across it. Concentrating drainage into one discharge point in karst country is worth a second thought before you dig.
• Freeze and thaw. Moderate through the Piedmont and heavier in the Blue Ridge and the western mountains. An open layer with water able to leave it heaves far less than a layer holding water in place.

The lane, the path and the seeding job, taken one at a time

A long rural lane. The lane body is not this product. It wants a compacted dense-graded base, which here means 21A, with a wearing course over it. What this stone is very good at is the wet section of that lane, the stretch that stays soft after a wet spell. Excavate it out, separate it, put in a drainage lift of clean stone, then build the base back over the top. That is a targeted fix rather than a surfacing material.

A garden path. Clean 3/4 inch stone is awkward to walk on. The pieces are big enough to roll under a shoe and too big to settle into a comfortable surface. A path wants Screenings if it is being bedded and compacted, or Walkway Gravel if it is being bought as a finished surface. This stone only appears on a path job as the drainage layer under a boggy section.

Ground being prepared for a new lawn. No stone belongs in the seed bed; that is Top Soil. But a lawn that drowns every spring often needs a curtain drain cut across the top of the slope before the topsoil goes down, and this is the stone that fills it. Do that first, then grade and seed.

Depth in a trench, a drainage lift and a wall zone

• Curtain or under-drain trench: typically 18 to 24 inches deep and around a foot wide, with pipe bedded low and stone over the top, all of it wrapped in separation fabric.
• Drainage lift under a base on a soft spot: 6 inches is a common working figure, separated above and below.
• Wall backfill: a vertical zone behind the wall face, built up in lifts with the backfill, following whatever the wall system or the engineer specifies.
• Pipe surround: to the drawing, not to a rule of thumb.

Nothing here is compacted to a density target. Clean stone cannot reach one.

Working out the 60 foot wet stretch, a path and a curtain drain

Cubic feet come from length times width times depth, all in feet. Divide by 27 for cubic yards. This site's calculator pages put 3/4 inch crushed stone at about 2,800 lb per cubic yard, roughly 1.40 tons.

• Example, the wet 60 ft stretch of an 11 ft wide lane, with a 6 inch drainage lift: 60 x 11 x 0.5 = 330 cu ft. 330 / 27 = 12.2 cubic yards, about 17.1 tons.
• Example, a curtain drain 70 ft long, 1 ft wide, filled 18 inches deep: 70 x 1 x 1.5 = 105 cu ft. 105 / 27 = 3.9 cubic yards, about 5.5 tons.
• Example, the garden path that should not have this stone on it, 45 ft by 3.5 ft at 2 inches of screenings: 157.5 sq ft x 0.167 = 26.3 cu ft. 26.3 / 27 = 1 cubic yard. Screenings run about 2,900 lb per cubic yard on this site's figures, roughly 1.45 tons, so about 1.4 tons.

For a trench that changes depth along its run, split it into sections, work out each one, and add the results rather than averaging by eye. The stone calculator will check any of the figures above.

Set your quantity and a delivery date here once the trench is open and the spoil is out of the way. Delivery is arranged at checkout from your ZIP code, and the truck needs clear access to somewhere it can tip.