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Rafter Framing: Common, Hip, and Valley Rafter Calculations
How to calculate rafter lengths for common, hip, and valley rafters. Unit run/rise, bird's mouth cuts, rafter tails, and roof area estimation.
Roofing Material Estimation: Squares, Slope Factor, and Waste Allowance
How to estimate roofing materials for shingles and metal panels. Slope factor, squares, bundles, underlayment, ice and water shield, and waste allowance.
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Calculate the exact BTU output your shop or garage heater needs. Factors in wall R-values, ceiling insulation, slab edge loss, overhead door infiltration, and air changes per hour to size propane, natural gas, and electric heaters correctly.
Overhead Door Infiltration Loss Calculator
Calculate heat loss through overhead doors in shops, garages, and warehouses. Compares open-door vs closed-door losses, seal condition impact, and annual cost of infiltration with payback on door seals and high-speed doors.
Long-Run Voltage Drop Calculator
Calculate voltage drop for long wire runs to detached shops, barns, garages, and outbuildings. Compares copper vs aluminum, shows motor starting voltage impact, and recommends the right wire size for your distance and load.