Concrete Foundation Calculator
Strip Footing Calculator
Calculate concrete volume, bags needed, and cost for continuous strip footings and foundation walls. Perfect for residential and commercial projects
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Why Choose Our Concrete Foundation Calculator?
Professional concrete foundation calculator for wall footers, continuous footings, and strip foundations with accurate volume and cost estimates.
Foundation Calculator
Calculate concrete for wall foundations, continuous footings, and strip footings. Supports linear measurements for wall footers.
Wall Footer Volume
Accurate concrete volume for wall footers and continuous footings using length × width × depth formula for strip foundations.
Foundation Cost Calculator
Calculate foundation cost with bag quantities (40lb, 60lb, 80lb) and ready-mix pricing for wall footers and continuous footings.
Wall Foundation Calculator
Calculate concrete for retaining walls, stem walls, and foundation walls. Imperial or metric measurements supported.
Strip Footing Calculator
Calculate concrete for continuous strip footings and trench footings. Linear measurement support for long wall foundations.
Free & Easy to Use
Free concrete foundation calculator for wall footers, strip footings, and continuous foundations. No registration required.
How to Calculate Concrete for Wall Foundations
Follow these steps to calculate concrete for wall footers, continuous footings, and strip foundations with accurate volume estimates.
Measure Wall Footing Dimensions
Measure the length of your wall, footing width (typically 2× wall thickness), and footing depth (usually 8-12 inches).
Tip: For continuous walls, measure total linear feet. Standard footing width = 2× wall thickness.
Enter Foundation Dimensions
Input length, width, and depth into the foundation calculator. Select imperial (feet/inches) or metric (meters/cm) units.
Note: Calculator uses length × width × depth formula for continuous wall footers and strip footings.
Review Foundation Volume & Bags
See concrete volume in cubic yards and bags needed (40lb, 60lb, 80lb) for your wall footer or strip footing instantly.
Important: For multiple wall sections, add lengths together or calculate each section separately.
Estimate Foundation Cost
Enter concrete price per bag or cubic yard to get instant cost estimate for your wall footer or strip footing project.
Pro Tip: For long continuous footings (>5 cu yd), ready-mix delivery is often more economical than bags.
Foundation Concrete Formula
Wall Footer Volume Formula:
Volume = Length × Width × Depth
Imperial Calculation:
Volume (cu yd) = (Length ft × Width in × Depth in) ÷ 324
Metric Calculation:
Volume (cu m) = Length m × Width cm × Depth cm ÷ 10000
Standard Wall Footing Sizes:
- • 8" wall: 16" wide × 8" deep footing
- • 10" wall: 20" wide × 10" deep footing
- • 12" wall: 24" wide × 12" deep footing
- • Rule: Footing width = 2× wall thickness
Frequently Asked Questions
Common questions about concrete foundation calculations, wall footer sizing, continuous footing requirements, and foundation cost estimation.
How to calculate concrete for a foundation?
To calculate concrete for a foundation wall footer, multiply length × width × depth. For a 50ft long × 16-inch wide × 8-inch deep wall footer, you need approximately 1.65 cubic yards. Our foundation calculator automatically includes the 10% waste factor and provides instant calculations for accurate footing planning.
How much concrete for wall footers?
Wall footer concrete depends on wall length and footing dimensions. For example, an 8-inch wall needs a 16-inch wide × 8-inch deep footer. A 30ft wall footer would need approximately 1.0 cubic yards or 34 bags of 80lb concrete mix. Use our foundation calculator to determine exact quantities for your wall footing project.
What is a concrete foundation calculator?
A concrete foundation calculator is a specialized tool that computes concrete volume needed for wall footers, continuous footings, and strip foundations. It calculates cubic yards, bags needed, and costs based on your wall length, footing width, and depth. Our calculator handles all conversions automatically for both imperial and metric units.
What size should wall footings be?
Wall footing width should be at least 2× the wall thickness. Standard sizes: 8-inch wall needs 16"W × 8"D footer, 10-inch wall needs 20"W × 10"D footer, 12-inch wall needs 24"W × 12"D footer. Footing depth typically ranges from 8-12 inches depending on soil conditions and building codes.
How deep should foundation footings be?
Foundation footings must be below the frost line, which varies by region from 12 inches in warm climates to 48+ inches in cold areas. Minimum depth is typically 8-12 inches. Check local building codes for frost depth requirements. Our calculator helps estimate concrete needed for any foundation depth specification.
Do I need rebar in wall footers?
Yes, wall footers typically require horizontal rebar for reinforcement. Standard practice uses two #4 rebar bars running lengthwise, placed 3 inches from the bottom. Vertical dowels extending into the wall are also common. Check local building codes for specific rebar requirements in foundation footings.
What is the difference between strip footing and spread footing?
Strip footings (also called wall footers) are continuous foundations running along walls, while spread footings support individual columns or piers. Strip footings distribute loads linearly along the wall length, whereas spread footings distribute loads in a square pattern around a single point. Our calculator is optimized for continuous wall foundation calculations.
How much does a concrete foundation cost?
Foundation costs vary by project size and method. Bagged concrete costs $6-8 per 80lb bag, while ready-mix costs $100-150 per cubic yard. A typical 100-foot wall footer might cost $200-400 in materials. Our calculator provides accurate cost estimates based on current pricing and helps you compare bagged vs ready-mix options.
Can I pour wall and footer together?
While possible, it's generally not recommended to pour wall and footer simultaneously. Standard practice is to pour the footer first, let it cure for 24-48 hours, then pour the wall. This creates a proper bond and allows for inspection. Monolithic pours require special engineering approval and reinforcement details.
How much concrete per linear foot of wall footing?
Concrete needed per linear foot depends on footing size. For a 16"W × 8"D footer: 0.033 cubic yards per foot. A 20"W × 10"D footer: 0.051 cu yd/ft. A 24"W × 12"D footer: 0.074 cu yd/ft. Our calculator automatically computes total volume based on your wall length and footing dimensions.
Should I include a waste factor for footings?
Yes, always include 10-15% waste factor when ordering concrete for wall footers. This accounts for spillage, over-excavation, and measurement variations in trenches. Our foundation calculator automatically includes 10% waste factor in all volume calculations, ensuring you order sufficient concrete for your footing project.
When should I use ready-mix vs bagged concrete?
Use ready-mix for footings over 2 cubic yards (about 60+ linear feet of standard footing). Ready-mix is faster and more consistent for large foundation projects. Bagged concrete works well for smaller wall footers, repairs, or projects under 1-2 cubic yards. Our calculator shows costs for both options.
What PSI concrete should I use for foundations?
Use 3000 PSI concrete minimum for residential wall footers and foundations. 3500-4000 PSI is recommended for commercial foundations or areas with freeze-thaw cycles. Higher PSI provides better durability and load-bearing capacity. Always check local building codes for minimum strength requirements in your area.
How do stepped footings work on slopes?
Stepped footings are used on sloped terrain to maintain proper depth. Each step should be at least 2 feet long and the vertical rise should not exceed the footing depth. Steps create a stair-like pattern following the slope. Calculate each level separately and add volumes together for total concrete needed.
Do I need gravel under wall footers?
Yes, a 4-6 inch gravel base is recommended under wall footers for proper drainage and stable support. Use crushed stone or gravel compacted to create a level base. This prevents settling, improves drainage, and provides a stable platform for concrete placement. The gravel layer also helps prevent frost heaving in cold climates.
Concrete Calculation Guide
Essential knowledge for accurate concrete calculations, measurement tips, and project planning guidelines.
Footing Measurement
- • Measure footing length along wall centerline
- • Footing width = 2× wall thickness minimum
- • Standard footing depth: 8" to 12"
- • Account for stepped footings on slopes
- • Measure below frost line depth
- • Add excavation overdig (4-6" each side)
Foundation Specifications
Standard Footing Sizes:
- • 8" wall: 16"W × 8"D footing
- • 10" wall: 20"W × 10"D footing
- • 12" wall: 24"W × 12"D footing
Code Requirements:
- • Minimum depth: 12" below grade
- • Below frost line: 12"-48" varies
- • Rebar: #4 continuous required
Cost Estimation
Ready-Mix Concrete:
$100-150 per cubic yard delivered
Rebar & Materials:
$0.50-0.75 per linear foot
Labor (if hiring):
$4-8 per square foot installed
Project Planning
- • Order 10-15% extra concrete
- • Schedule delivery for early morning
- • Have tools ready before mixing
- • Check weather forecast (no rain)
- • Prepare sub-base and forms first
- • Plan for immediate use of mixed concrete
Cost Considerations
- • Bagged: $6-8 per 80lb bag
- • Ready-mix: $100-150 per cubic yard
- • Delivery fees: $50-100 typical
- • Minimum orders may apply
- • Weekend/overtime rates higher
- • Compare total project cost, not just per-unit
Quality Tips
- • Use proper water-to-cement ratio
- • Avoid adding excess water
- • Consolidate concrete to remove air
- • Level and smooth surface properly
- • Allow adequate curing time
- • Protect from temperature extremes
Quick Reference: Common Footing & Foundation Sizes
| Footing Type | Size (W×D) | Per 10 ft (cu yd) | Estimated Cost |
|---|---|---|---|
| 8" Wall Footing | 16" × 8" | 0.33 cu yd | $35-50 |
| 10" Wall Footing | 20" × 10" | 0.51 cu yd | $55-75 |
| 12" Wall Footing | 24" × 12" | 0.74 cu yd | $75-110 |
| Column Pad 24×24 | 24" × 12" | 0.22 cu yd | $25-35 |
| Column Pad 30×30 | 30" × 12" | 0.35 cu yd | $35-50 |
* Costs based on ready-mix concrete at $100-150/cu yd. Add rebar and labor for total project cost.