Cattle guard sizes: width, depth, and how to pick
Every cattle guard has two dimensions, and only one of them is "the size." The width — the span across your road — is the number you buy: 8, 10, 12, or 14 feet. The depth is how far the grid runs in the direction of travel. Five minutes here and you'll know exactly what to order.
Which number is the size you buy?
Width is the span across the road, gate-post to gate-post. When someone says "I need a 12-foot cattle guard," this is the 12. It's the dimension that has to match your opening, and it's how every guard on our size and price table is listed.
Depth is the distance in the direction of travel — the gap an animal would have to jump to get across. Powder River builds two: 7'5" and 8'. One note, because it causes real confusion: you'll see the shallower one listed as "7.5 ft" on other sites. The actual dimension is seven feet five inches — 7'5" — not seven and a half feet.
How wide should a driveway cattle guard be?
Wide enough to cover the full traveled surface, and matched to the opening in your fence. A 12-foot opening takes a 12-foot guard — our 12' × 8' HS20 at $4,899 is the flagship of the line for a reason: it fits the common ranch entrance and carries the rating county trucks expect.
One exception worth thinking about before you order: how traffic enters. If trucks and stock trailers turn into your entrance off a narrow road, they cut the corner, and the trailer tracks inside the truck's line. A 14-foot guard gives that swing room so nobody drops a wheel off the edge of the grid.
What about county roads and double lanes?
For anything a county truck, school bus, or loaded semi will cross, the de facto standard is HS20 — 16 tons per axle. Our load ratings guide covers what the ratings mean in plain numbers; the short version is that rating and size are separate choices, and public-road work usually dictates the rating for you.
Spans from 16 to 24 feet and true double-lane guards exist, and we sell them — by phone. Specs and freight vary too much to publish a flat price, so call (800) 555-0143 — a real person responds within four business hours.
Does the guard need to match my gate opening?
Yes — the guard is replacing the gate, so it should fill the same hole. Match the opening or go one size over. Never under: a guard narrower than its opening leaves a strip of ground on either side, and cattle will find it.
Small gaps between the guard ends and your fence posts are a different problem with a cheap fix. Wings — angled panels that bolt to the guard ends and run back to the fence — close the skirt-around route. They're $569 a pair and ship on the same truck as the guard, so they add no freight.
Is 8-foot depth worth it over 7'5"?
Usually, yes. The extra depth makes the gap longer in the one direction that matters to an animal deciding whether to try it. The upcharge across our line is $100 to $300 depending on the model — small insurance on a purchase you make once.
Two cases decide themselves: if you need a U-54 or U-80 rating for heavy commercial traffic, those are only built in 8' depth. And if you're pricing to the last dollar for a light-duty private driveway, the 7'5" H-15 guards are the least expensive in the line, starting at $3,299.
When should you size up?
Buy the width your entrance will need in five years, not the one it barely needs today. The step from a 12' to a 14' HS20 in 8' depth is $900. Replacing an undersized guard later means buying a whole second guard and paying freight twice. Steel is cheap the first time.
Size up when trailers or equipment wider than a pickup use the entrance, when traffic turns in tight off the road, or when you're planning to widen the gate anyway. And plan your unloading before any size arrives: an 8-foot guard weighs about 1,000 lb and a 14-foot about 1,800 lb, so you'll need a tractor, loader, or forklift on site. We deliver. We do not install.
Sizing questions
What size cattle guard fits a 12-foot gate opening?
A 12-foot guard. Width is measured across the road, same as a gate opening, so match the numbers: 12-foot opening, 12-foot guard. If there's a small gap left between the guard ends and your fence posts, a pair of wings closes it — they bolt to the guard ends and angle back to the fence.
What's the difference between 7'5" and 8' depth?
Depth is the distance an animal would have to clear in the direction of travel — the longer the gap, the more committed the jump. Both depths carry the same width and rating options in the H lines, but the heavy U-54 and U-80 ratings are only built in 8' depth. Stepping up from 7'5" to 8' runs $100 to $300 depending on the model.
Do you sell 16-foot, 20-foot, or double-lane cattle guards?
Yes — spans from 16 to 24 feet and true double-lane guards are quoted by phone, because specs and freight vary too much to publish a flat price. Call (800) 555-0143 and a real person will spec it with you.
Does a 14-foot guard cost a lot more to ship than an 8-foot?
Less than you'd guess. An 8-foot guard weighs about 1,000 lb and a 14-foot about 1,800 lb, but freight depends on the lane as much as the weight — typical delivered freight anywhere in the lower 48 is $500 to $1,300. Whatever the number is, you see it at checkout and it's final. No second charge later.
Can I set two guards side by side to cover a wide entrance?
Call us first. For one wide opening, a single 16- to 24-foot span is usually the cleaner answer, and we quote those by phone. Where two guards genuinely make sense — two separate entrances on the same place — order them together: the second guard on the same shipment adds roughly a third of the first one's freight.
Still unsure? That's a two-minute phone call.
Tell us the opening, the traffic, and the state it ships to — a real person will land you on the right guard. (800) 555-0143.
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