Concrete Resources

Calculators, pour-season data, Specs, — the same information we use to plan your job.

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Volumetric Mixing

Most concrete arrives pre-mixed in a barrel truck: batched at a plant, mixed in the drum, and racing its own clock on the drive to you. Ours arrives as raw materials — cement, aggregate, sand, water, and admixtures in separate bins — and gets metered and mixed at your pour. We run two ProAll P95 volumetric mixers, the largest in ProAll’s lineup, and we’re growing the fleet. Here’s what mixing on site actually changes:

  • You pay for what you place: A plant order is a guess made in round numbers, padded “just in case,” and anything you don’t use is money in the return load. A volumetric truck meters volume as it mixes — 6.2 yards means 6.2 yards. On small pours the difference is the whole economics of the job: work to small to justify a plant delivery is routine for us, which is why our minimum is only 4 yards.
  • The concrete is always fresh: Drum concrete starts curing the moment it’s batched — the drive, the wait on site, the wait between placements all come out of its usable life, and a delay long enough means rejecting the load. On a volumetric truck, nothing is concrete until we make it concrete. Mixing starts when the crew is ready to place, and pauses when they’re not. A form problem or a slow section costs minutes, not a load.
  • The mix can change mid-pour: Stiffer for a slope, wetter for a tight finish, a different mix for the footing than the slab — adjustments happen at the truck, on the spot. With a plant, a mix change means a phone call and another truck.
  • Perfect for small and remote pours: Jobs too small for a plant ticket, sites too far out for a comfortable haul time, and projects that need concrete in stages over a day — the truck handles all three, because distance and timing don’t age the product on the way.

What you should know

Not every crack is a problem

Concrete shrinks as it cures, so hairline cracks appear in nearly every slab — control joints exist to give them a straight, planned place to happen. A hairline in or near a joint is the system working.

Call about the other kind: one side sitting higher than the other, a crack running the slab’s full depth, or one still growing a year later. Those point at water or soft ground underneath — and patching the crack won’t fix the base. Unsure? Send us a photo with something for scale.

THe base decides the Lifespan

Concrete is strong in compression, weak in bending. On solid, compacted ground a slab just gets compressed; on soft ground it bends — and bending is what cracks it. A four-inch slab on a proper base outlasts a six-inch slab on ground somebody just smoothed over.

Base work is invisible once the concrete’s finished, which is exactly where a low bid saves its money. Compare bids by asking what each contractor does below the concrete — that answer is the real price difference.

Weather sets the schedule

Concrete doesn’t dry — it cures, through a reaction that’s picky about temperature. Above 95°, fresh concrete loses water faster than it can use it and permanently stops gaining strength; the fix is early pours, a mix adjusted on site for the day, and keeping the surface damp. Below 40°, curing stalls without protection. Rain during a pour damages the finish, so we reschedule — a delayed pour costs a day; a rained-on pour can cost the slab. Spring and fall are easy; the right crew pours all year.

Curing isn’t the same as drying

A slab looks done in days. It isn’t — concrete gains strength for about 28 days, two-thirds of it in the first week. During that window it’s strong enough to look trustworthy and weak enough to be damaged in ways that never heal: park a truck on it at day three and the micro-cracking is permanent.

Foot traffic at 24–48 hours, passenger vehicles at about a week, heavy loads at 28 days. We give you the exact dates before we leave — curing is the cheapest step of the job and the easiest to ruin.

Volumetric-mixed concrete is produced under ASTM C685 (Standard Specification for Concrete Made by Volumetric Batching and Continuous Mixing), the counterpart to ASTM C94 for plant-batched ready mix.

For independent guidance on concrete materials and practices, the Portland Cement Association (cement.org) and the American Concrete Institute publish homeowner- and specifier-facing resources we’re happy to be measured against.

Verti-block Retaining Wall Systems

We supply and install Verti-Block — a large-format concrete block that dry stacks without mortar, so retaining walls go up faster with less labor and less time the site is tied up. The blocks are load-bearing and the finished face is uniform enough to leave exposed, which makes them a fit for grade changes, embankments, drainage channels, and erosion control. Data sheets & cut sheets for each block type and more info are available on our dedicated Verti-Block site: gcastinc.com.

Concrete Calculator

How much concrete does your project need?

Set the dimensions and get the volume in cubic yards. Every figure here is an estimate for planning, not a quote.

Overage allowance

Overage covers subgrade that is not perfectly flat, spillage, and the concrete left in the chute. Order 5 percent over on clean, well-prepped work and 10 percent on rough grade or a form-heavy pour.

Concrete placed

0.00cu yd

Barrel-truck order with overage 0.00 cu yd

That overage is what a pre-mixed barrel truck order costs you, because the load is batched before it leaves the plant. We mix on site and meter as we place, so you pay for the volume that goes in the ground.

An estimate for planning. Final volume depends on subgrade, forms, and how the site actually measures out. We confirm quantities at the site visit.

Concrete Calendar

When should you pour in Fort Smith?

There is no month we will not pour in. There are months that need more planning, and knowing which is which before you schedule saves you the surprise.

Every figure below is an average, not a forecast: the typical overnight low and afternoon high for that month across the last ten years. Individual days run well past both ends — July afternoons above 100F and January mornings in the teens are both normal here.

  • Ideal pour window
  • Pours fine with precautions
  • Cold-weather measures required
  • Jan 30–52°F Cold-weather measures
  • Feb 35–58°F Cold-weather measures
  • Mar 44–68°F Precautions
  • Apr 50–75°F Ideal
  • May 60–82°F Ideal
  • Jun 70–91°F Precautions
  • Jul 73–95°F Precautions
  • Aug 71–94°F Precautions
  • Sep 66–89°F Precautions
  • Oct 53–78°F Ideal
  • Nov 42–65°F Precautions
  • Dec 35–57°F Cold-weather measures

Ideal pour window

April, May, October

Moderate temperatures let concrete cure at a steady rate without heat or cold working against it. These are the months every contractor in the valley is trying to schedule, so call earlier than you think you need to.

Pours fine with precautions

March, June, July, August, September, November

Two different problems at opposite ends of the year. Through the summer we shift pours to early morning, use chilled water or ice in the mix, dampen the subgrade, and start curing immediately so the surface does not dry before it gains strength. In March and November the risk is a cold snap landing on a slab that is two days old, so we watch the forecast and keep blankets on the truck.

Cold-weather measures required

December, January, February

We pour through the winter. It takes insulating blankets, heated enclosures on some work, warmed mixing water, and accelerating admixtures, and we protect the slab for several days after placement rather than walking away from it. What it costs you is a little more lead time and a little more money, not the project.

Not sure when to schedule? Tell us the project and we will tell you the realistic window.

Average daily high and low for Fort Smith over the last ten years (2016-2025), calculated from National Weather Service monthly temperature records for Fort Smith and benchmarked against the NWS 1991-2020 climate normals. We publish the recent decade rather than the thirty-year normal because the last ten years have run warmer here, most of it in autumn and winter. These are averages, not extremes — July days above 100F are routine, and that is what we actually schedule around. Fort Smith monthly temperature records, National Weather Service.

FAQ

It depends on square footage, thickness, reinforcement, how much demo and haul-off is involved, and how hard the site is to access. That’s why the estimate happens on site — a number over the phone is a guess, and tends to move as work starts. It’s also why bids for the same job come back different: one includes proper excavation, base, and compaction, another assumes the existing ground is fine. The slab can look identical on paper while the site prep — the part that decides the lifespan — differs by thousands.

Yes, but it’s small — about 4 cubic yards. Because we mix on site with a volumetric truck and you pay for the volume placed, jobs that wouldn’t justify a barrel-truck delivery are practical for us. For scale, 4 yards is roughly a 215-square-foot slab at 6 inches thick — a small patio or a walkway. If you’re not sure where your project lands, the calculator above can help you in about a minute.

Stay off it on foot for 24 to 48 hours, and keep vehicles off for about a week. Concrete reaches full design strength around 28 days — it’s usable well before then, but curing continues the whole time and the first seven days matter most. A week is enough for normal passenger vehicles, and we’ll be able to give you a specific date before we leave.

Spring and fall — moderate temperatures let concrete cure at a steady pace. Summer pours work fine with an early start and a crew that manages moisture; winter pours need protection below 40° and have a schedule advantage, since it’s the slow season. The pour-season chart above shows the full year month-by-month.

Not during it. Rain on fresh concrete damages the surface finish and can weaken the top layer. We watch the forecast and schedule around it — a delayed pour costs a day; a rained-on pour can cost the slab.

Often, yes — especially for new driveways, anything near a public right-of-way, and structural work. Requirements vary by city, and we pull what the job needs before we start, including scheduling any inspections (footings and reinforcements are typically inspected before the pour).

Yes. We coordinate with general contractors, project managers, engineers, and inspectors as a routine part of commercial and municipal work, and we’re used to scheduling around active sites. Because we have engineers on staff, plan questions and field conflicts usually get answered the same day instead of going back through a third party.

Yes. We’re licensed through the Arkansas Contractors Licensing Board and carry general liability and workers’ compensation coverage. We’ll send certificates of insurance with any bid, or before work starts on smaller jobs.

Rough dimensions, what the surface needs to hold (foot traffic, passenger vehicles, trucks, equipment), your timeline, and anything you already know about the site — slope, drainage problems, existing concrete to remove. Don’t worry about being too precise. The calculator above will get you a rough volume if you want a head start.

Yes — we supply and install Verti-Block retaining wall systems for contractors and developers on a subcontract basis, and we bid municipal wall work directly. Data sheets can be found on our website gcastinc.com.

Ready to talk about your project?

Send us the details or just call. We’ll take a look at it, tell you what it needs, and how we can do it.

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