Barndominium concrete floors in Texas: a regional guide

Barndominium concrete floors in Texas are usually one slab finished two ways. The living end gets polished concrete, and the shop bay gets a polyaspartic or epoxy coating. Living areas pour 4 inches thick at 4,000 PSI or better, and shop bays run 5 to 8 inches. On a 2,400 square foot barndo, the slab alone runs $12,750 to $37,100 before the drive cost, which is our trip out to your site.

A steel shell with a home inside fits cheap rural land, farm and ranch life, and the Texas love of a big shop next to the house. The slab is the barndo’s foundation and its finished floor. It carries the building, holds it down against the wind, and shows under your feet every day. A mistake made before the concrete gets ordered can’t be fixed after the pour.

We work two parts of Texas, and they’re different jobs. North Texas is the 940 area code, from Wichita Falls and Stephenville over to Gainesville and Sherman. East Texas is the 903 area code, from Texarkana and Paris down through Mount Pleasant, Marshall, and Longview. The soil, the weather, and the right mix all change between them. A spec sheet that ignores which one your slab sits in is guessing.

The Texas state hub shows where we work. For more on each service, see our Texas barndominium polished concrete and Texas barndominium slab pages.

How do North Texas and East Texas barndo regions differ?

A spec that holds up in Wichita Falls isn’t the right spec for Marshall. The ground and the air are too different.

North Texas (940 area code). This is ranch country and rolling Cross Timbers. The main soil is black expansive clay from the Blackland Prairie, a clay that swells when it’s wet and shrinks when it dries. Bands of caliche and limestone gravel show up toward the Permian Basin. In most North Texas counties, the clay’s plasticity index runs past 30, per Texas AgriLife Extension soil data. That’s a lab number for how much a clay moves. July afternoons of 95 to 105 degrees F are normal. Winters bring three to five hard freezes, and humidity runs 50 to 60 percent most of the year. Wind across the open prairie also dries fresh concrete faster than a pour at the same heat in East Texas.

East Texas (903 area code). This is piney woods. The main soil is silt loam over sandstone or shale, with pockets of sandy loam along I-30 from Texarkana through Paris. It holds weight better than Blackland clay, but the air runs 70 to 80 percent humidity through the warm months, and the region gets 45 to 55 inches of rain a year. Winters are milder, with one or two freezes. The hard part here is getting a coating to stick, because more water vapor pushes up through the slab than in drier states.

So a clay package built for North Texas is more than East Texas silt loam needs. And a 16 inch rebar grid that works fine in Marshall is too light for Blackland clay near Sherman. Soil doesn’t average out across the state. Pick the spec for your region before anyone writes the mix ticket.

What slab spec does a Texas barndominium need?

The slab carries the metal shell, the wind loads, and the finished floor in two different rooms. ACI 360 is the design guide for a slab poured on the ground.

Mix. Use 4,000 PSI at least, measured at 28 days. PSI is the strength rating on the mix ticket. We add synthetic fiber at the plant to control shrinkage cracks, on top of the rebar. This is the line owners try to trim first, and it’s the wrong one. A 3,000 PSI mix leaves a softer top that won’t grind to a clean polish, and it’s weaker at the edges, right where the anchor bolts hold the building down in a wind. Once the truck leaves, there’s no fixing it.

Vapor barrier. A 15 mil plastic vapor barrier (Stego Wrap or equal) goes under the whole living-space slab, laid right on a packed gravel base. Don’t skip it on any slab you might coat or polish later.

Steel. On North Texas clay, use #4 rebar on a 12 to 16 inch grid both ways, with the slab edge thickened to 16 inches. Some North Texas sites use post-tension cable instead, which is steel cable pulled tight after the pour. On East Texas silt loam, #4 rebar on 16 inch centers does the job without the thicker edge. Welded wire mesh is fine for small side pours, but not for the main slab.

Thickness. Living areas get 4 inches. Shop bays for cars and pickups get 5 to 6 inches. Heavy-equipment areas get 8 inches, with 10 to 12 inch thick pads under each post-frame column or lift base.

Insulation. Rigid foam rated R-10 runs around the edge of the living-space slab. Frost doesn’t go deep in Texas, so this is about a warm floor inside, not about frost.

For more on the slab itself, see our Texas barndominium slab page and our barndominium shop slabs service.

Where does the concrete come from, and how does it polish?

Texas concrete isn’t all the same. The rock in the mix changes between regions, and you can see it in the finished floor.

North Texas. Plants pull limestone from Texas quarries west of I-35 and gravel from pits along the Red River. The stone is light colored, and it polishes well to a cream or salt-and-pepper look. A 4,000 PSI mix carries 5.5 to 6.5 sacks of cement. For a slab you’ll polish, we hold the water-cement ratio (the water in the mix for each pound of cement) at 0.45 or lower. That means a superplasticizer, an additive that loosens the mix, goes in at the truck. Nobody should be hosing water into the mix on site just to make it pour easier.

East Texas. Plants around Texarkana and Marshall use East Texas sandstone, river gravel from the Sulphur and Red rivers, and limestone trucked in from the north. That stone runs darker and less even. It gives a richer salt-and-pepper polish, but the thin cream layer on top needs a careful eye. The cement and water targets match North Texas.

Pour-4-Polish works the same way in both regions. If you plan to polish, the pour spec gets locked before the concrete is ordered. That means FF 35 at least (FF is a flatness score, and higher is flatter), FF 50 for a premium polish, no acrylic curing compound, and control joints saw-cut inside 36 hours.

Do Texas barndo slabs need moisture testing before coating?

Water vapor coming up through the slab is the most common reason a coating fails in its first year. We check every slab first. A test comes next when the slab shows a warning sign, like a floodplain site, an old coating that failed, or no one knowing how old the slab is. We’ll run one any time you ask, too. East Texas slabs raise that flag more often, because the wet air keeps more moisture in the slab all year than in the drier country to the west.

There are two tests. The calcium chloride test (ASTM F1869) measures the pounds of moisture that come out of 1,000 square feet in 24 hours. When it reads over 3 pounds, we add a moisture barrier primer before the coating. The probe test (ASTM F2170) drills to 40 percent of the slab’s depth and reads the humidity there. Most polyaspartic and epoxy systems draw that line at 75 percent.

North Texas slabs cure in drier air, and they usually read lower at 60 to 90 days. East Texas is different. Slabs there sit in 70 to 80 percent humidity through the warm months, and many of them don’t pass without help. That help is a moisture barrier primer, at $1.80 a square foot. The other choice is grinding a failed coating off the slab later and doing the whole job again.

Texas humidity climbs as you drive east, and it shows up on the barndo slabs we test. A Wichita Falls pour in October reads about 4 pounds on the calcium chloride test at 90 days. That’s close, but it’s still over our 3 pound line, so it gets the moisture barrier primer. The same pour in Marshall reads 6 to 7 pounds, and it needs that primer before any polyaspartic or epoxy goes down. On a slab with a warning sign, skipping the test is the most expensive shortcut on a Texas barndo. The coating peels in 8 to 14 months, and the only fix is grinding back to bare concrete and starting over. Every reading goes on the project sheet with the pour ticket.

Polished concrete, coatings, or sealed slab: which finish?

There are four choices. Each one costs a different amount and lasts a different length of time. Pick by what really happens in that room, not by what looks nicest in a showroom.

Polished concrete. We grind the slab with diamonds in four to six passes. A lithium silicate densifier, a liquid that hardens the concrete, goes on after the 200-grit pass. The final polish stops at 400 or 800 grit. It’s permanent. The surface gets harder over time instead of wearing out, and a 20-year-old polished slab can be polished again for a fraction of the first cost. It also handles moisture coming up through the slab, which matters more in East Texas. See our polished concrete service page.

Polyaspartic coating. This is a 100 percent solids system. A base coat goes down, then vinyl chip or quartz gets spread until the base won’t hold any more (installers call that full rejection). A clear polyaspartic topcoat that won’t yellow in the sun seals it, 20 mils thick in all. It stands up to sun and chemicals, and you can drive on it in 24 hours. It’s the standard spec for a Texas barndo shop bay. See our garage floor coatings service.

Epoxy coating. This is 100 percent solids epoxy with a urethane topcoat. It stands up to wear, but not to sun, and it yellows within two years under direct light. It fits a covered shop bay where no window lets sun onto the floor.

Sealed concrete. A densifier soaks in, and a sealer goes on top. It’s the cheapest of the four to put in. A handy homeowner can do it if they’re comfortable prepping a floor. But it needs a reseal every 2 to 3 years, and it won’t protect against the farm chemical spills common in Texas barndo shops.

Most Texas barndos in both regions go polished in the living end and polyaspartic in the shop. East Texas jobs often step up to a coating that resists chemicals better, because rural shops there more often store farm chemicals.

How much does a Texas barndo concrete floor cost?

Three things move the price per square foot from one region to the next: how far our crew drives, what the local ready-mix plant charges, and local labor rates.

Slab pour. A slab we pour runs $5.32 to $15.61 a square foot. North Texas Blackland clay with engineered steel lands toward the top of that range. Caliche and limestone sites in North Texas land lower, and so does East Texas silt loam around Marshall, Mount Pleasant, and Texarkana. To price a heavier shop bay, slide the thickness setting in the quote tool up to 6 or 8 inches.

Polished living area. Polished concrete runs $3.83 to $6.25 a square foot. The low end is our base polish, which is a cream finish with no stone showing. Salt-and-pepper is the most common pick in both regions. For that look, we grind deeper to show the fine stone, then grout the pores. That option adds $1.20 a square foot, plus $1.63 a foot of edge. Dye adds $0.70.

Shop bay coating. Sealed concrete runs $1.31 to $3.42 a square foot. It’s fine for light storage, but it does nothing against the hydraulic fluid and farm chemical spills most Texas barndo shops see. RESA is our own line of resin floors. Epoxy floors (our RESA Quartz and RESA Metallic) run $6.08 to $10.17. Our RESA Flake floor, color flake sealed in resin, runs $8.55 to $10.39 on its standard epoxy build. The 1-day polyaspartic build is priced per job, after we see the floor. Polyaspartic is the toughest system, and it’s our standard spec for Texas shop bays.

A whole barndo. Take a 2,400 square foot barndo with a 1,400 square foot living end and a 1,000 square foot shop. The slab runs $12,750 to $37,100. Polishing the living end runs $5,500 to $8,950. A flake floor in the shop runs $8,650 to $10,500 on the standard epoxy build. We price the example on that build because it’s the one the quote tool prices; the polyaspartic build we spec for most shops is priced per job. All three totals are before the drive cost. Put our SPEC pour and the polish on one quote, and you save 30% on field and edge polishing.

The drive cost on a Texarkana quote won’t match one for Wichita Falls, because the drive and the ready-mix plants differ. For more detail, see our Texas concrete driveway cost and Texas polished concrete cost pages. Our national overviews live at polished concrete and concrete flatwork.

How does Texas climate affect a barndo pour?

Texas weather fights the pour in summer and the cure in winter.

Summer pours. When the surface tops 90 degrees F or the wind runs over 10 mph, water leaves fresh concrete faster than it can rise back to the top. That causes plastic shrinkage cracks, fine cracks that open in the first hour. ACI 308 calls for an evaporation retarder on hot, windy days, then a wet cure or a clear dissipating cure for the first seven days. From late June through August, we move heavy pours to early morning, when the air and the trucks are still cool. In East Texas, a pour in thunderstorm season can also leave blotchy spots on a slab that will be coated.

Winter pours. The ACI 306 cold-weather steps kick in when the air drops below 40 degrees F in the first 72 hours after a pour. North Texas sees three to five freezes each winter, and East Texas sees one or two. The steps are warm mix water (60 to 80 degrees F at the truck), insulated curing blankets, and slab temperatures held above 50 degrees F for 72 hours. Concrete that freezes can lose up to 50 percent of its design strength for good.

Spring and fall (April, May, October, November). These are the best months in both regions, with mild heat, lower humidity, and a cure you can predict. Book early. Spring slots fill by February, and fall slots fill by August.

Five Texas barndo mistakes to avoid

We see the same five across North and East Texas. Each one is cheap to prevent while you plan and costly after the pour.

1. Pouring 3,000 PSI to save money. Our SPEC pour is 4,000 PSI or better, placed flat enough to polish. On our quote, the step up from a standard pour adds $0.64 a square foot. What a 3,000 mix saves won’t cover even one square foot of tear-out when the slab cracks early or won’t grind clean.

2. Skipping the vapor barrier under the living space. Our 15 mil barrier runs $0.60 a square foot. Leaving it out is the surest way to a failed coating on a Texas barndo, because the barrier protects the coating, the polish, and any floor you lay on top for the life of the building. Forget it and there’s one fix. You tear out the slab and pour a new one.

3. Hand-screeding a slab you’ll polish. A hand screed is a board pulled by hand to level wet concrete. It leaves a 3/8 inch rise or dip over a 10 foot span. Polishing needs FF 35 at least, and that takes a laser-guided screed. A hand-screeded slab can be coated or sealed. It can’t be polished unless you spend the polish budget grinding the high spots flat first.

4. Using an acrylic curing compound on a slab you’ll polish. Acrylic cures don’t work with polishing chemistry. Use a clear dissipating cure or a wet cure on any pour you plan to polish.

5. Skipping the moisture test on an East Texas slab with a warning sign. We add the moisture barrier primer when the calcium chloride test reads over 3 pounds or the probe reads over 75 percent. East Texas slabs often go over both, and without the primer the coating peels up in the first year. We price a test per job, after we see the slab. It’s the cheapest insurance on the project.

Get a Texas barndo concrete quote

One slab, two finishes, one spec. You get polish in the living end and polyaspartic in the shop, from a single pour whose finish was set before the forms went up. Decide early, not after. Crews dispatch from Wichita Falls for North Texas addresses and from Texarkana for East Texas addresses. The shop slab runs through our barndominium shop slabs service, and the full Pour-4-Polish spec that ties the pour to the finish lives on our Pour-4-Polish overview.

Tell the online quote tool your project type, square footage, and address, and get your price in about two minutes. The drive cost shows as its own line, so you see it before you commit.