Custom & Automatic Gate Installation in Knoxville, TN

An automatic gate is a machine, and there is a standard for it

A driveway gate with an operator on it is not a fence with a motor attached. It is powered equipment that moves several hundred pounds of steel across a space where people and cars are, and there are two published standards that govern it: UL 325 covers the operator, and ASTM F2200 covers how the gate itself is built. Most homeowners have never heard of either, and it is worth knowing what they say before you buy.

Operator class has to match the property

UL 325 sorts vehicular gate operators into four classes. An operator listed for the wrong class is the single most common thing we find wrong on gates installed by someone else:

A Class I residential operator on an apartment complex entrance is a listing violation, and it is the kind of detail that matters if anything ever goes wrong.

Two independent means of entrapment protection — and they must be monitored

UL 325 requires at least two independent protective means for each entrapment zone. Inherent sensing built into the operator counts as one. The second is typically a non-contact sensor (photo eye) or a contact sensor (safety edge).

The part people miss: since the 7th edition tables took effect on 1 August 2018, external entrapment devices must be monitored. The operator checks that the device is present and working at every cycle, and refuses to run if it is not. An unmonitored photo eye wired into a modern operator is not compliance — it is a disconnected safety device waiting to be discovered.

How the gate itself has to be built

ASTM F2200 governs construction of the automated gate. The dimensions are specific:

• Gaps between the gate panel and any support structure such as a post: no more than 2¼ inches.
• From grade up to 48 inches, openings must be guarded or screened so a 2¼-inch sphere cannot pass through.
• Between 48 and 72 inches, a 4-inch sphere must not pass through.
• Bottom edges smooth, with vertical protrusions no greater than ½ inch. Protrusions are otherwise not permitted, apart from ornamental pickets, locks, wheels and positive stops.
• Exposed rollers less than 8 feet above grade must be guarded or covered.
• Positive stops are required at both fully open and fully closed.
• On a swing gate, at least 16 inches between the gate and any fixed object, and a post or column covered by the gate in the open position may not exceed 4 inches wide.

A gate that fails these is not a gate that will necessarily fail tomorrow. It is a gate that will fail an inspection, void a manufacturer's warranty, and sit badly in an insurance claim.

What a gate costs in Knoxville

Gate posts are the part that decides whether a gate still closes in year five. A gate post carries a cantilevered load that a line post never sees, so it is bigger, set deeper, and often concreted differently. On a Knox County lot that can mean hitting rock — depth to bedrock runs from about 7 inches on a Montevallo soil to more than 60 on Corryton. Ask what happens to the price if the auger stops early, and whether that is in the quote or a change order.

Three things people get wrong on driveway gates

1. Swing direction and slope. A gate that swings inward up a rising driveway will not clear the grade. On a slope you either swing out, regrade the arc, or go to a slide gate.
2. Throat depth. If the gate sits right at the road, a vehicle waiting for it to open is still in the traffic lane. Setting the gate back a car length off the pavement is a safety decision, not an aesthetic one.
3. Power and a way out. The operator needs a power run to the gate, and you need a plan for a power cut — a manual release, and something that lets a visitor or a delivery out without a remote.

Where the local rules touch gates

• Corner lots. Both the City of Knoxville and Knox County restrict obstruction to vision near intersections, and a solid gate panel counts. Knox County fence rules covers the detail; Lenoir City and Loudon County use the same 3½-to-10-foot band at different distances.
• Pool gates are a code matter, not a style choice. Self-closing, self-latching, swinging outward away from the pool, with the latch release at 54 inches or pool-side at least 3 inches below the top. Pool barrier requirements.
• 811 before the operator trench. Running power to a gate is excavation. Tennessee requires 3 working days' notice; the ticket is good for 15 days.

Gate repair

Most gate problems are one of four things: a sagging gate frame that has racked out of square, a gate post that has shifted in clay, worn or undersized hinges, or an operator whose safety devices have failed or been bypassed. A gate that latched perfectly in April and drags in September usually moved with the ground, not the hardware — East Tennessee subsoil runs 35 to 60 percent clay and shrink-swell is real here. Fence and gate repair in Knoxville.

More on fencing and gates

• Fence installation in Knoxville, TN
• Knoxville fence contractors — what we build and what it costs
• Commercial automated gates and access control
• Commercial dumpster enclosures
• Commercial fencing in Knoxville
• All 28 fence answers

Standard references summarised from ANSI/UL 325 (vehicular gate operators) and ASTM F2200 (automated vehicular gate construction), current as of September 2026. Standards are revised; confirm current requirements and your operator's listing with the manufacturer and your local authority having jurisdiction.