Feet-Inch Math on Site: Stair Stringers Made Simple
Feet-inch arithmetic without errors, the three stair proportion rules, and a full stringer layout from floor height to cut length.
App guides
Construction Expert A1 Pro
Feet-inch construction maths for framing pros — stairs, rafters, roof pitch, and the arithmetic that trips people up.
10 Reasons US Contractors Are Switching to Construction Expert A1 Pro
Ten common US jobsite problems, from wrong rafter cuts and failed stair inspections to NEC wire sizing, and how Construction Expert A1 Pro solves each.
Why Thousands of US Contractors Are Replacing Their $100 Hardware Calculators With This App
How Construction Expert A1 Pro replaces a hardware calculator: feet-inch-fraction math, rafter and stair layout, 7 trade calculators and PDF reports.
Construction Expert A1 Pro
These guides explain the calculations behind the app. See what it does and how it works offline.