Most prefabricated steel bridges are set in place in a single day, with the full process — from site prep to a crossing you can drive across — typically taking anywhere from a few days to two weeks. The bridge itself often lands in hours. What stretches the timeline is everything around it: the foundations, the weather, and how ready your site is. Because the span is built and welded in a controlled shop before it ever reaches your property, the slow, weather-dependent work of pouring and curing a bridge on-site is almost entirely removed.

Here’s a realistic look at what goes into the timeline, what speeds it up, and what slows it down.

How long does prefab bridge installation actually take?

For a private or light-commercial crossing, the on-site work generally breaks down like this:

• Setting the bridge: Often just a few hours once the foundations are ready. A crane or excavator lifts the prefabricated span into position and crews bolt it down.
• Foundation work: 1–5 days, depending on whether you’re using simple concrete footings, helical piers, or a prepared gravel base.
• Finishing: Decking, railings, and approach grading usually add another day or two.

By contrast, a traditional cast-in-place concrete bridge of similar size can take several weeks to a few months, largely because concrete has to be formed, poured, and cured on-site before it can carry any load.

What does the installation process look like, step by step?

1. Site evaluation and foundations

Before anything is set, the crossing point is assessed for span length, bank stability, and how water moves through the channel during high flow. Foundations — concrete footings, abutments, or piers — are then prepared to match. This is the single biggest variable in your timeline, because it depends on soil conditions and the foundation type your site calls for.

2. Delivery to your property

Your bridge is fabricated off-site and shipped to you ready to install. Smaller spans frequently arrive in one piece, fully assembled, which removes field welding and on-site fabrication from the equation entirely.

3. Setting the span

With foundations cured and ready, the bridge is lifted into place. Many of our crossings can be set with a small crew and standard lifting equipment — an excavator or a modestly sized crane — rather than the heavy specialized fleet a poured structure demands.

4. Decking, railings, and final grading

Once the span is anchored, the driving or walking surface is finished, safety railings are installed, and the approaches are graded so the transition onto the bridge is smooth. After a final inspection, the crossing is ready for use.

What affects your installation timeline?

Several factors can shorten or extend the schedule:

• Foundation type: A simple footing on stable ground is fast. Deep piers in soft or rocky soil take longer.
• Site access: Easy equipment access to the bank speeds everything up. Remote or rugged sites add staging time.
• Weather: Concrete foundations need dry conditions to cure properly, and high water can pause work.
• Span size and load rating: A pedestrian trail bridge goes in faster than a heavy vehicular crossing rated for loaded equipment.
• Permitting: If your crossing affects a regulated waterway, permit review can run in parallel but should be started early.

Why does prefab install so much faster than a poured bridge?

The speed advantage comes down to where the work happens. With a prefabricated steel bridge, the structure is engineered and built in a shop under controlled conditions, then delivered complete. Connections are bolted rather than welded in the field, which means less skilled labor and less equipment on your site. A cast-in-place bridge, by comparison, turns your property into the construction site — forms, rebar, poured concrete, and days of curing all happen at the crossing, exposed to weather the entire time.

What crew and equipment do you need on-site?

For most private and light-commercial crossings, you don’t need a specialized bridge crew. A small team with an excavator or compact crane can handle the set, and the bolt-together design means no field welding. That’s a meaningful cost difference on top of the time savings, because you’re not mobilizing a large crew or renting heavy equipment for weeks.

Frequently asked questions

Can a prefab bridge be installed in one day?

The span itself is frequently set in a single day. The full project timeline depends on foundation work, which is prepared before the bridge arrives. If your footings are ready, set day can be remarkably quick.

Do I need a crane to install a prefabricated bridge?

Not always. Smaller spans can be placed with an excavator, while larger or heavier bridges call for a crane sized to the lift. The right equipment depends on the weight and reach your specific crossing requires.

How far in advance should I order?

Because your bridge is built to your span and load requirements, fabrication lead time is the main thing to plan around. Reaching out early lets us align fabrication with your foundation schedule so the two are ready at the same time.

Will I need a permit?

It depends on your location and whether the crossing affects a regulated waterway. Many private crossings on small drainages are straightforward, but it’s always worth checking local requirements before you break ground.

Ready to put a timeline on your crossing? Every site is different, and the fastest way to get a real schedule is to tell us about yours. Request a quote and we’ll help you map out foundations, delivery, and set day for your property.

For most private, agricultural, and light-commercial crossings, a prefabricated steel bridge is the better choice — it installs faster, costs less to build and maintain over its life, and spans longer distances with smaller foundations. Concrete still makes sense for certain heavy highway structures and decorative architectural spans, but for a creek, ditch, or low-water crossing on your property, steel almost always wins on speed, cost, and long-term value.

Here’s how the two materials really compare across the things that matter.

Steel vs. concrete bridge: the quick comparison

At a glance:

• Installation speed: Steel is dramatically faster — often set in a day versus weeks of forming, pouring, and curing for cast-in-place concrete.
• Upfront cost: Competitive, and frequently lower for steel once you factor in smaller foundations and less site labor.
• Lifespan: Both are long-lived; galvanized steel spans routinely last 75–100+ years.
• Maintenance: Galvanized steel needs very little; concrete can crack, spall, and need repair over time.
• Span length: Steel’s strength-to-weight ratio lets it cross longer distances without intermediate piers.

Cost: upfront price vs. lifetime cost

It’s easy to compare two bridges by sticker price alone, but that misses where the real money is. Steel’s light weight means smaller, simpler foundations and less heavy equipment on-site — savings that show up before the bridge is even set. Over the full life of the structure, independent life-cycle studies have found galvanized steel bridges can be cost-competitive with, and sometimes cheaper than, the best concrete alternatives, in part because future maintenance costs are so much lower.

A poured concrete bridge can look cheaper on paper but carry hidden costs: more extensive foundations to support its weight, a longer construction schedule, and crack-and-spall repairs down the road.

Installation speed

This is steel’s clearest advantage for property owners. A prefabricated steel bridge is built in a shop and delivered ready to install, so the span itself can often be set in a single day. A cast-in-place concrete bridge has to be formed, reinforced, poured, and cured at the crossing — a process exposed to weather that commonly runs several weeks or more. If you need access restored quickly, steel is the obvious pick.

Lifespan and durability

Both materials last a long time when designed and maintained properly. Permanent bridges are typically engineered to a 75-year design service life, and in long-term studies of in-service bridges, steel I-beam structures showed among the longest average lifespans — with many galvanized steel bridges expected to perform well beyond 100 years. Steel also holds up well under extreme events like earthquakes, thanks to its strength and flexibility, and it’s the most recycled structural material in the world.

Maintenance

Here’s where the long-term gap opens up. A hot-dip galvanized steel bridge resists corrosion for decades with minimal upkeep — the zinc coating does the work. Concrete, by contrast, is prone to cracking, spalling, and rebar corrosion over time, especially where water and freeze-thaw cycles are involved, and those repairs add up. Life-cycle research has put the present value of future maintenance for galvanized steel at roughly half that of comparable concrete structures.

When does concrete make sense?

Steel isn’t the answer to every bridge. Concrete has real strengths and is the right call in specific cases:

• Heavy, high-volume highway structures where mass and stiffness are design priorities.
• Architectural or decorative spans where concrete can be molded into custom shapes and finishes.
• Very short, simple culvert-style crossings where a precast box may be the most economical option.

For the kind of crossings most landowners, farms, ranches, golf courses, and developers need, though, those advantages rarely outweigh steel’s speed and life-cycle savings.

So which should you choose?

Choose a prefabricated steel bridge if you want fast installation, lower lifetime cost, minimal maintenance, and a longer clear span over a creek, ditch, or wash. Consider concrete if you’re building a heavy highway-grade structure, need a custom architectural form, or are crossing a very short span where a precast culvert fits. For nearly everything in between — the private and commercial crossings we build every day — steel is the stronger value.

Frequently asked questions

Is a steel bridge cheaper than a concrete bridge?

Often, yes — especially over the full life of the structure. Steel’s light weight reduces foundation and labor costs upfront, and its low maintenance keeps lifetime costs down. Exact pricing depends on span, load rating, and site conditions.

How long does a steel bridge last?

Permanent bridges are generally designed for at least 75 years, and galvanized steel spans frequently last well beyond 100 years with minimal maintenance.

Do steel bridges rust?

Properly galvanized or coated steel is highly corrosion-resistant. The zinc layer on hot-dip galvanized steel protects the structure for decades before any significant maintenance is needed.

Which installs faster, steel or concrete?

Steel, by a wide margin. A prefabricated steel span can often be set in a day, while a cast-in-place concrete bridge typically takes weeks to form, pour, and cure on-site.

Not sure which is right for your crossing? Tell us about your span, your load needs, and your site, and we’ll help you weigh the options. Request a quote and get a straight answer for your property.