★★★★★
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Optimized for iPhone Duo and iPad: on wide screens, inputs and results now sit side by side so you can see the answer change as you type. Built with the iOS 27 SDK.
Guessing at baluster spacing wastes material and risks failing inspection. The 4-inch sphere rule sounds simple, but getting even gaps across an odd-length span requires math. This app does it instantly. Enter total span between posts, baluster width, post width, and max allowed gap (IRC 4-inch residential or IBC 6-inch commercial preset). Get the exact number of balusters, actual gap size, on-center spacing, and instant code pass/fail check. Supports deck railings, stair railings, fence sections, and porch guards. IRC R312.1 and IBC compliant gap limits built in. Shows full layout summary with post-to-baluster spacing. KEY FEATURES: - IRC and IBC gap presets - Even spacing calculation - Code compliance check - Works completely offline - No account or login required Built for deck builders, carpenters, general contractors, and home inspectors.