Footings are where a lot of small projects stall out. They're structural, they're inspected, and hand-digging them to code depth in clay is the kind of work that turns a weekend project into three weekends.
A hydraulic auger on a mini skid steer drills a clean, plumb, consistent hole in a fraction of the time — provided the bit diameter and the machine's hydraulics are matched to each other.
Before You Dig
Call 811. Always, and well before you plan to start — locate requests typically need a few business days. An auger will go through a gas line, a fiber run, or a service lateral without slowing down.
Confirm your code requirements. Footing diameter and depth aren't preferences — they come from the structural load and your local frost depth, and both are set by your building department. Get the requirement in writing before you drill, not after.
Check whether you need a permit and an inspection. Most structural footings require both, and many jurisdictions want to inspect the open hole before concrete.
Verify the auger matches the machine. Larger bit diameters need substantially more torque, and torque comes from hydraulic flow and pressure — not engine horsepower. A machine that spins an 8-inch bit easily may stall on an 18-inch bit in the same soil. Check the drive unit's flow requirement against the machine's published auxiliary flow.
Hydraulic HP = (GPM × PSI) ÷ 1,714
What You'll Need
Attachments: Auger with the correct bit diameter, plus extensions if your frost depth requires them
Tools: Layout string and stakes, tape, level, spade or clamshell digger for cleanup
Optional: Rock bit with carbide teeth if you're in stony ground
Steps
1. Lay out and mark. String lines and stakes for every hole location. Verify diagonals for square before you drill anything — moving a hole after the fact is not a small job.
2. Position the machine square to the hole. The auger drills where the machine points it. Take the extra ten seconds to line up rather than correcting a leaning hole.
3. Start slow. Let the bit find its own center before applying down pressure. Starting fast walks the bit off the mark.
4. Drill in stages. Advance, then raise the bit partially to clear spoil, then advance again. Trying to drill straight through packs the flights and stalls the bit. In clay especially, clearing frequently is what keeps you moving.
5. Check depth. Measure rather than assuming. Frost depth requirements are exact and inspectors check.
6. Clean the bottom. Augers leave loose spoil in the hole. That material compresses under load, which defeats the point of the footing. Clean it out with a clamshell digger or spade.
7. Check plumb. Sight or measure before you set anything.
Common Mistakes
Not calling 811. The most expensive mistake available in this work.
Oversizing the bit for the machine. An under-fed auger stalls, heats the hydraulic system, and tries to rotate the machine instead of the bit. Match the specs before you buy either one.
Leaving spoil in the hole. Loose material at the bottom compresses. The footing settles. Clean it out.
Drilling in saturated soil. Wet clay smears the sidewalls and holes can collapse. Wait if you can.
Forcing a binding bit. When the auger stops turning and the machine starts turning, stop and reverse. That's rock, root, or too much diameter for conditions.
Guessing at code depth. Get the requirement from your building department in writing.
Which Yellow Jacket Model
YJ1000 / YJ1100 — deck and pergola footings in typical residential diameters.
YJ1200 — more capacity for larger diameters and harder ground.
YJ2000 — for large structural footings, post-frame columns, or consistently rocky soil. The hydraulic capacity is what drives big bits.
FAQ
How deep do footings need to be?
Set by your local frost depth and structural requirements, which vary enormously by region. Your building department has the number. Don't rely on what a neighbor did.
What bit diameter do I need?
From the structural design — footing diameter comes from the load being carried. Confirm before you buy an auger, because bit diameter drives which machine you need.
Will it work in rocky soil?
Clay, hardpan, and small stone, yes. Larger rock and ledge stop any auger in this class. A carbide rock bit helps; it doesn't eliminate the problem. In consistently rocky ground, expect some holes to need other methods.
Can it drill through roots?
Small roots yes, large roots poorly. Roots are also a sign you may want to reconsider the location for the tree's sake.
How many footings can I do in a day?
Varies enormously with soil, depth, and diameter — but hole digging generally stops being the limiting factor, and layout and setting become the constraint.
Do I need an inspection?
Almost certainly for structural work. Many jurisdictions inspect the open hole before concrete, so don't pour ahead of the inspector.