Digging Fence Posts in Aurora: JULIE and the Frost Line

Nobody digs until the lines are marked. In Aurora, the contractor or owner has to contact JULIE to mark all utilities before digging post holes. Anyone digging in Illinois has to notify JULIE at least the required notice period ahead, no matter how small or shallow the hole. The request and the marking are free.

Depth comes next. The frost line in Aurora sits at 3 feet 6 inches below finished grade. That depth is the line we dig to. A post footing that stops above it sits in soil that freezes and lifts. That lift shows up later as a loose post, a gate that drags, or a latch that no longer lines up.

Position matters too. No part of the fence, including posts and footings, can extend past the property line. A fence cannot enclose a utility box. Grading at the property line stays as it is unless the city approves a grading plan.

Layout: We measure and lay out the fence line. We walk the property with you and take field measurements. We mark the fence line, the post spacing, and the gate openings. Gate posts carry more load than line posts, so we locate hinge posts and latch posts first and space the line posts from there.

Pre-marking: We pre-mark the dig area. When a dig site cannot be clearly described in the locate request, the excavator has to mark it with white paint, flags, or stakes before contacting JULIE. We paint or flag each post location and the run between them so the locators know exactly where we plan to dig.

Locate request: We call in the locate. We submit the request at least the required notice period before digging. The utility companies, not JULIE itself, send their own crews to mark their lines. Gas, electric, water, and communication lines each get marked by the company that owns them.

Mark check: We check the marks against the layout. Once the paint and flags are down, we walk the fence line again. If a marked line runs through a planned post hole, we shift the post, adjust the spacing, or change the panel layout. We also check for utility boxes. If the fence line would close one in, we reroute the fence so the box stays outside.

Digging: We dig the post holes. We dig each hole below 42 inches, and wider at gate posts. A driveway gate puts heavy, constant leverage on its hinge post. That post gets the deepest, widest footing on the job. Near marked lines, we dig by hand.

Footings: We set the posts in concrete footings. We plumb each post, brace it, and pour the footing. We crown the top of the concrete so water runs away from the post instead of pooling against the metal. We check post height and alignment before the concrete sets.

Hanging: We hang panels and gates after cure. Once the footings have cured, we mount panel brackets, hang the fence panels, and set hinges and latches. On sloped ground we rack or step the panels to follow the grade. Then we adjust the hinges, check swing clearance and ground clearance, and align the latch.

For the full sequence from first visit to final adjustment, see our fence and gate project process. For permit steps, see Aurora fence permits.

The frost line drives most of what we do at the post hole. Water in the soil expands as it freezes and pushes up on anything anchored too shallow. A fence post set too shallow can rise a little each winter. Over a few seasons, a gate that closed clean starts to bind, sag, or drag on the drive.

So we take the footing below the frost line. The bottom of the concrete sits in soil that stays unfrozen, and the post holds its height through freeze and thaw.

The property line limits where that footing can go. Posts and footings stay entirely on your side. A footing is wider than the post it holds, so we set posts in from the line far enough to keep the full footing on your property.

Grading at the line stays put. We do not cut down or build up soil at the property line to level a fence run. On grade changes, we rack or step the panels. Where the ground drops enough to leave a gap under a panel, we set post heights and panel positions to close it without moving soil at the line.

We work this way across Aurora, from the Tanner Historic District to Oakhurst, and in nearby towns like Naperville and North Aurora.

Do I need to call JULIE for just a few post holes?

Yes. The advance notice applies to any digging, no matter how small. One post hole for a new gate counts. When we do the work, we place the request.

How deep do fence posts go in Aurora?

We dig them below the depth where the ground freezes. That is Aurora's frost line. We dig gate posts wider than line posts because they carry the swing load.

Does the locate cost anything?

No. JULIE notification and the utility marking that follows are free.

What happens if a marked line runs where a post needs to go?

We move the post. We adjust the post spacing or panel layout to clear the line. If the change affects a gate opening, we show you the new layout before we dig.

My existing posts are loose. Were they set too shallow?

Often, yes. Posts that lift or lean after winter usually have footings above the frost line. We check the footing depth and reset the posts below 42 inches. See gate and fence repair.

Call (630) 473-9918 or contact us for metal fence or gate work in Aurora. Tell us where the fence will run and where the gates go. We will measure the site, call in the locate, and set every post below the frost line. For the installation itself, see metal fence installation and driveway gate installation.