Fill the form and press Calculate to see results here.
Project Inputs
Example Data Table
Sample inputs and typical outputs for a mid-size renovation scenario.
| Scenario | Length (ft) | Width (ft) | Fixed Area (sq ft) | Wall Removal (lf) | Net Area (sq ft) | Total Cost |
|---|---|---|---|---|---|---|
| Open living + kitchen | 40 | 28 | 85 | 32 | 1035 | USD 34,900 |
| Small apartment refresh | 26 | 18 | 40 | 14 | 428 | USD 13,600 |
| Large open concept remodel | 55 | 35 | 140 | 48 | 1785 | USD 58,400 |
Numbers are illustrative and vary by region, scope, and finish level.
Formula Used
- Gross floor area (sq ft) = Length × Width
- Net open area (sq ft) = Gross area − Fixed elements area
- Estimated occupants = ⌊ Net open area ÷ Occupant load factor ⌋
- Demolition cost = Total wall removal (lf) × Demolition rate
- Disposal cost = Total wall removal (lf) × Disposal rate
- Structural cost = (Beam length × Beam cost) + (Post count × Post cost) + Engineering allowance
- Flooring cost = Net open area × Flooring cost per sq ft
- Finishes cost = Net open area × Finishes cost per sq ft
- Electrical cost = (Fixtures × Cost per fixture) + (Outlets/switches × Cost per outlet/switch)
- Direct subtotal = Sum of all direct costs and fees
- Labor add-on = Direct subtotal × Labor %
- Contingency = (Direct subtotal + Labor) × Contingency %
- Tax = (Direct + Labor + Contingency) × Tax %
- Total project cost = Direct + Labor + Contingency + Tax
- Cost per sq ft = Total project cost ÷ Net open area
How to Use This Calculator
- Measure the combined footprint and enter total length and width.
- Estimate any fixed areas that won’t be “open” (stairs, island, built-ins).
- Add interior wall segments you plan to remove and mark load-bearing where needed.
- Enter local rates for demolition, disposal, and finishes based on quotes.
- If structural support is needed, enter beam length, posts, and engineering allowance.
- Set labor, contingency, and tax percentages to match your estimating method.
- Press Calculate and review the breakdown above the form.
- Use the download buttons to export the latest results for records.
Planning Notes
An open layout often improves circulation and sightlines, but it can shift loads, airflow, acoustics, and lighting needs. Use the wall type selector to flag structural risk early.
If you remove any load-bearing length, include realistic allowances for beams, posts, and engineering. Your final design may also require rerouting plumbing, sprinklers, or low-voltage wiring.
For occupant guidance, choose a factor that matches your intended use and local expectations. This tool provides a planning estimate, not a code determination.
Plan smarter, build safer, and enjoy your open space.