Volume
30 × 50 × (4 ÷ 12)Net volume is 500.00 ft³Estimated. With 10% added, the total is 550.00 ft³Estimated.
2026 U.S. cost and quantity estimate
30x50 Concrete Slab Cost
In 2026, a 30x50 concrete slab needs about 20.37 cubic yardsEstimated at 4 inches thick with 10% added and has a modeled national installed cost of $9,000–$18,000Estimated.
Installed estimate uses HomeGuide's $6–$12/sq ft national range, February 3, 2026. Quantity uses the dimensions and allowance shown.
30x50 concrete slab cost calculator
Adjust thickness, allowance, or metro area. All four planning results update in one step and remain in your browser. You can also compare concrete slab cost by size.
Concrete volume
20.37 yd³
Includes selected allowance Estimated
80 lb concrete bags
917 bags
Whole bags, rounded up Estimated
Installed project cost
$9,000–$18,000
United States — national average Estimated
Installed price per sq ft
$6.00–$12.00
Thickness and metro adjusted Estimated
How to use this 30x50 calculator
01
Keep or change the footprint
The page starts at 30 ft by 50 ft. Changing either field recalculates area, volume, bags, and price.
02
Compare thickness
Switch among the supplied 4, 5, and 6 inch planning scenarios to see how volume changes.
03
Set the allowance
The default is 10%. This factor is applied after the rectangular slab volume is calculated.
04
Select the metro
The nearest listed metro changes only the modeled labor share. It does not claim a supplier quote.
30x50 slab calculation formula
The calculation moves from volume to cubic yards, then applies the relevant unit price.
Cubic yards and bags
550.00 ÷ 27 = 20.37 yd³Bag count divides the same volume by the verified 0.60 ft³ per 80 lb bagVerified, then rounds up.
Price
Quantity × unit price = costMaterial cost uses $120–$160/yd³Verified, HomeGuide, April 3, 2026. Installed cost starts with $6–$12/sq ftVerified.
Installed thickness model. HomeGuide reports that materials make up 50%–60%Verified and labor 40%–50%Verified of slab cost, February 3, 2026. This page uses midpoint shares of 55% material and 45% laborEstimated to model thickness and metro differences.
Concrete slab prices by size
These links keep the 2026 national installed benchmark visible across existing size pages.
| Size page | Area | 4-inch concrete | Installed cost | Data level |
|---|---|---|---|---|
| 10x10 concrete slab cost | 100 sq ft Estimated | 1.36 yd³ Estimated | $600–$1,200 Estimated | National installed baseline Estimated |
| 12x12 concrete slab cost | 144 sq ft Estimated | 1.96 yd³ Estimated | $860–$1,730 Estimated | HomeGuide $6–$12/sq ft, Feb. 3, 2026 |
| 20x20 concrete slab cost | 400 sq ft Estimated | 5.43 yd³ Estimated | $2,400–$4,800 Verified | HomeGuide, Feb. 3, 2026 |
| 20x30 concrete slab cost | 600 sq ft Estimated | 8.15 yd³ Estimated | $3,600–$7,200 Estimated | National installed baseline Estimated |
| 30x30 concrete slab cost | 900 sq ft Estimated | 12.22 yd³ Estimated | $5,400–$10,800 Estimated | National installed baseline Estimated |
| 30x40 concrete slab cost | 1,200 sq ft Estimated | 16.30 yd³ Estimated | $7,200–$14,400 Estimated | National installed baseline Estimated |
| 30x50 concrete slab cost | 1,500 sq ft Estimated | 20.37 yd³ Estimated | $9,000–$18,000 Estimated | HomeGuide $6–$12/sq ft, Feb. 3, 2026 |
| 40x60 concrete slab cost | 2,400 sq ft Estimated | 32.59 yd³ Estimated | $14,400–$28,800 Estimated | HomeGuide $6–$12/sq ft, Feb. 3, 2026 |
| 60x80 concrete slab cost | 4,800 sq ft Estimated | 65.19 yd³ Estimated | $28,800–$57,600 Estimated | HomeGuide $6–$12/sq ft, Feb. 3, 2026 |
30x50 slab thickness by use
The three thicknesses below are comparison scenarios supplied for estimating. They are not structural specifications or construction guidance.
Patio scenario
4 in Estimated20.37 yd³Estimated with the default allowance. Modeled installed range: $9,000–$18,000Estimated.
Garage and driveway scenario
5 in Estimated25.46 yd³Estimated. Modeled installed range: $10,240–$20,480Estimated.
Metal-building and load-bearing foundation scenario
6 in Estimated30.56 yd³Estimated. Modeled installed range: $11,480–$22,950Estimated.
Installed ranges in these scenarios use HomeGuide's $6–$12/sq ft national benchmarkVerified, dated February 3, 2026, with the disclosed thickness model applied where noted.
Concrete quantity and material cost by thickness
All rows cover 1,500 sq ftEstimated and include the default 10% allowance.
| Thickness | Cubic yards | 80 lb bags | Approx. weight | Ready-mix material cost |
|---|---|---|---|---|
| 4 in | 20.37 yd³ Estimated | 917 Estimated | 77,000 lb / 38.50 tons Estimated | $2,440–$3,260 Estimated |
| 5 in | 25.46 yd³ Estimated | 1,146 Estimated | 96,250 lb / 48.13 tons Estimated | $3,060–$4,070 Estimated |
| 6 in | 30.56 yd³ Estimated | 1,375 Estimated | 115,500 lb / 57.75 tons Estimated | $3,670–$4,890 Estimated |
Installed prices in this table use a single national $6–$12/sq ft baseline and do not change by thickness. See how price shifts by slab depth →
Material estimate: cubic yards × $120–$160/yd³ ready-mixVerified, HomeGuide, April 3, 2026. Weight uses 140 lb/ft³Verified, QUIKRETE technical data revised October 2022. Bag yield is 0.60 ft³Verified per 80 lb bag from the same sheet.
30x50 slab cost by metro area
Metro estimates adjust the labor share with BLS May 2025 construction and extraction wages. They do not represent ZIP-code or supplier quotes.
| Metro area | BLS construction wage | Modeled $/sq ft | 30x50 installed total | Level |
|---|---|---|---|---|
| Dallas concrete cost | $27.03/hr Verified | $5.62–$11.25 Estimated | $8,430–$16,870 Estimated | BLS May 2025 model |
| Chicago concrete cost | $40.87/hr Verified | $6.81–$13.62 Estimated | $10,220–$20,440 Estimated | BLS May 2025 model |
| Seattle concrete cost | $42.11/hr Verified | $6.92–$13.84 Estimated | $10,380–$20,760 Estimated | BLS May 2025 model |
| Atlanta concrete cost | $28.26/hr Verified | $5.73–$11.46 Estimated | $8,590–$17,190 Estimated | BLS May 2025 model |
Sources: BLS OEWS metro data, May 2025, and HomeGuide's $6–$12/sq ftVerified national range, February 3, 2026.
What is a 30x50 concrete slab used for?
A 30x50 footprint contains 1,500 sq ftEstimated. The comparisons below describe area and cost scope only.
Garage
1,500 sq ft EstimatedYes, 30x50 is sold as a garage-and-shop size. Icon Steel describes this footprint as a 3-car garageVerified; source checked October 4, 2026. Actual capacity depends on bays, doors, walls, storage, and access.
Metal-building foundation
$11,480–$22,950 EstimatedThe concrete-only 6-inch scenario is modeled at $11,480–$22,950 installed. It uses HomeGuide's February 3, 2026 national benchmark and the disclosed thickness model. Reinforcement, the building kit, and site-specific engineering are outside this figure.
Large patio
3.75× a 20x20 EstimatedA 30x50 slab has 1,500 sq ftEstimated, compared with 400 sq ftEstimated for a 20x20 concrete slab. It is therefore a large patio footprint by area.
Commercial or storage floor
6 in+ scenario EstimatedFor cost comparison, this page groups commercial and warehouse floors with the supplied 6-inch-or-greaterEstimated scenario and keeps expansion-joint material separate. This is an estimating category, not a structural specification.
Renegade Steel Buildings lists 30x50 for vehicle storage, mechanic or fabrication shops, contractor storage, and light commercial use; source checked October 4, 2026.
DIY material baseline vs. installed price
This is a cost-scope comparison only. The two cards do not contain the same line items.
DIY: ready-mix material only
$2,440–$3,260 EstimatedCalculated as 20.37 yd³Estimated multiplied by HomeGuide's $120–$160/yd³Verified, April 3, 2026. Other materials, equipment, delivery modifiers, and labor are outside this card.
Contractor: installed benchmark
$9,000–$18,000 EstimatedCalculated from the 1,500 sq ftEstimated footprint and HomeGuide's verified $6–$12/sq ft installed national range dated February 3, 2026.
Modeled difference: $5,740–$15,560Estimated. This is the gap between a ready-mix-only amount and the installed benchmark, not a complete DIY budget.
Items that can change a 30x50 quote
These published unit ranges help identify which line item is moving a bid. They are not automatically included in every total.
Base preparation
$1–$3/sq ft VerifiedGravel pad-base pricing reported by HomeGuide, February 3, 2026. Across 1,500 sq ftEstimated, that is $1,500–$4,500Estimated.
Rebar or wire-mesh upgrade
+$1–$4/sq ft VerifiedReinforcement-upgrade impact from HomeGuide's contractor pricing guide, April 3, 2026. For this footprint: +$1,500–$6,000Estimated.
Expansion-joint material
$0.50–$2/LF VerifiedMaterial-only range from HomeGuide's contractor pricing guide, April 3, 2026. Installed joint labor may appear separately.
Stamped or decorative finish
+$3–$12/sq ft VerifiedPublished add-on from HomeGuide, April 3, 2026. Across 1,500 sq ftEstimated: +$4,500–$18,000Estimated.
30x50 concrete slab cost FAQ
How many cubic yards are needed for a 30x50 concrete slab?
A 30x50 slab at 4 inches thick needs about 20.37 cubic yards with 10% addedEstimated. The same footprint needs 25.46 yd³ at 5 inchesEstimated and 30.56 yd³ at 6 inchesEstimated.
How much does a 30x50 concrete slab cost in 2026?
The modeled national installed range is $9,000–$18,000 in 2026Estimated. That is 1,500 sq ftEstimated multiplied by HomeGuide's $6–$12/sq ftVerified benchmark dated February 3, 2026.
Should a 30x50 garage foundation be estimated at 4 inches or 6 inches?
This page compares a 5-inch garage/driveway case with a 6-inch metal-building/load-bearing case. The modeled installed ranges are $10,240–$20,480Estimated and $11,480–$22,950Estimated, respectively. These are estimating scenarios, not structural specifications.
Is a metal-building foundation priced separately?
Yes—the concrete slab and the metal building should be treated as separate price scopes. This page's concrete-only 6-inch model is $11,480–$22,950Estimated, based on HomeGuide's February 3, 2026 benchmark. The building kit, site-specific engineering, and separately quoted reinforcement are outside that total.
How many cars fit in a 30x50 garage footprint?
A manufacturer markets 30x50 as a 3-car garage and shop footprintVerified. The source is Icon Steel, checked October 4, 2026; actual capacity depends on bay layout, doors, walls, storage, and access.
How do I tell whether a 30x50 quote is reasonable?
Divide the quoted total by 1,500 sq ft and compare that unit rate with the metro-adjusted calculator range. Then compare separately listed base, reinforcement, joint, and finish charges with the sourced units on this page. The result is a price check, not a determination of required scope.
Got a quote? Send it over—we’ll help you check whether it looks reasonable.
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