This carpentry calculator estimates linear footage, corner miter cut waste, and board counts for baseboards, crown molding, and chair rails. When trimming a room, walls rarely measure exact board multiples, and cutting 45-degree inside and outside miter joints produces scrap pieces. This tool computes net perimeter, accounts for door opening subtractions, and calculates the exact number of standard stock boards needed.

### Trim Measurement Formulas The calculator processes room perimeter and opening dimensions in client state:

- **Door Opening Deductions:** Doorways remove floor-level trim runs. Evaluated as $\text{netPerimeter} = \max(0, \text{roomPerimeter} - [\text{doorOpeningsCount} \times 3\text{ ft}])$. - **Miter Waste Margin Allowance:** Evaluated as $\text{totalLinearFt} = \lceil \text{netPerimeter} \times (1 + \text{waste} / 100) \rceil$. - **Stock Board Sizing:** Evaluated as $\text{boardsNeeded} = \lceil \text{totalLinearFt} / \text{boardLengthFt} \rceil$. - **Total Stock Linear Footage:** Evaluated as $\text{totalStockFt} = \text{boardsNeeded} \times \text{boardLengthFt}$.

### Worked Numeric Example Suppose a homeowner trims a rectangular dining room using 12-foot primed pine baseboard boards: - **Room Perimeter Wall Length:** 64 feet - **Door Openings:** 3 doorways (subtracts $3 \times 3 = 9\text{ feet}$) - **Board Stock Length:** 12 feet - **Miter Waste Allowance:** 10%

**Step-by-Step Calculation:** 1. **Net Perimeter:** $64 - (3 \times 3) = 64 - 9 = 55\text{ linear feet}$. 2. **Total Footage with Waste:** $\lceil 55 \times 1.10 \rceil = \lceil 60.5 \rceil = 61\text{ linear feet}$. 3. **12-Foot Boards Required:** $\lceil 61 / 12 \rceil = \lceil 5.08 \rceil = 6\text{ boards}$. 4. **Total Stock Purchased:** $6 \times 12 = 72\text{ linear feet}$ of lumber.

### Client-Side Processing Note All calculations execute locally in client-side JavaScript. No floor plans, room dimensions, or renovation budgets are transmitted across any network.