6×6 Hot Tub Pad, 6 Inch Reinforced
A small 6 ft square, 6 in pad with a tight rebar grid for a hot tub.
Formula SSC-2026.1
Formula SSC-2026.1 · 4,000 PSI
Order volume
0.70 yd³
0.535 m³ placed+waste
Order weight
2,835 lb
1,286 kg
80 lb bags
32
1 pallets at 42 bags
60 lb bags
42
0.45 ft³ yield each
Rebar
84.00 ft
14 × 20 ft · 14 × 6 m · 59 lb
Ready-mix vs bags
$216.00
Truck $240.50 · 80 lb bags $216.00
Grid lines are equalized so the drawing stays readable. The order count uses on-center spacing with a bar at each end of the layout, then holds concrete cover in the field.
| Item | Net | Waste | Order | Unit price | Line total |
|---|---|---|---|---|---|
| Ready-mix concrete | 0.67 yd³ | 5% | 0.70 yd³ / 0.535 m³ | USD | $115.50 |
| Short-load fee | Under 4 yd³ | — | 1 truck @ 10 yd³ | USD | $125.00 |
| 80 lb pre-mix bags | 30.0 bags | 5% | 32 bags | USD | $216.00 |
| 60 lb pre-mix bags | 40.0 bags | 5% | 42 bags | USD | $226.80 |
| #4 rebar sticks, 20 ft | 14 sticks | 5% | 15 sticks / 14 × 6 m | USD | $210.00 |
| Rebar chairs | 49 crossings | 5% | 52 chairs | USD | $14.56 |
| Tie wire rolls | 49 ties | 5% | 1 rolls | USD | $8.00 |
Ready-mix truck
$240.50
0.07 nominal 10 yd³ loads · 1 to order
80 lb bags
$216.00
60 lb alternative $226.80 · delivery weight 2,835 lb
| Thickness | Order yd³ | Order m³ | 80 lb bags | Rebar ft | Ready-mix | 80 lb cost |
|---|---|---|---|---|---|---|
| 4 in | 0.47 | 0.357 | 21 | 88 | $202.00 | $141.75 |
| 6 in | 0.70 | 0.535 | 32 | 88 | $240.50 | $216.00 |
| 8 in | 0.93 | 0.714 | 42 | 88 | $279.00 | $283.50 |
Show the deterministic formula
Slab ft³ = L × W × thickness ÷ 12. Thickened-edge extra = footing band × (footing depth − slab thickness), with corner squares counted once.
yd³ = ft³ ÷ 27. m³ = ft³ × 0.0283168. Weight uses 150 lb/ft³, then the header converts that pound total at 1 lb = 0.45359237 kg. 80 lb bags yield 0.6 ft³ and 60 lb bags yield 0.45 ft³. Currency changes the price labels only.
Bars across a span = floor(span ÷ spacing) + 1. Order sticks = that count, plus 10, 5, or 15 percent waste, cut from 20 ft and 6 m stock. Chairs = one per grid intersection.
Contractor sign-off
Project: 6×6 Hot Tub Pad, 6 Inch Reinforced
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This sheet is an estimate for ordering and layout discussion. It is not a sealed design. Confirm the quantities with a licensed local professional and the authority having jurisdiction before you buy or build.
Engineering notes
A 6 by 6 ft pad at 6 in is 0.67 cubic yards before waste. That is a bag job unless you are already pouring something else. The default is #4 at 12 in on center and 5 percent waste. The order weight is the concrete only. Add the tub, water, and people on top of that number when you talk to the inspector. A filled tub is a concentrated load, so this page does not claim the pad is adequate by itself.
Code reference
IRC R506.1 sets a 3.5 in minimum for concrete slab-on-ground floors. Reinforcement cover and spacing follow ACI 318 practice and the local inspector. This quantity takeoff is not a soils or structural design.
Field questions
- How much concrete is a 6x6 by 6 inch pad?
- Placed volume is 18 cubic feet, or 0.67 cubic yards. With 5 percent waste the order is about 0.70 cubic yards.
- Why is the grid at 12 inches?
- The smaller spacing is a tighter mat for a point-loaded pad. It raises bar count, chairs, and tie intersections compared with an 18 in garage grid.
- Does the weight include the water?
- No. The weight is normal-weight concrete at 150 lb per cubic foot. The tub manufacturer publishes the filled weight you still have to support.