· FieldDojo Team · construction
Stair Rise and Run: Code Limits for the US, Canada, and the UK
How to lay out a staircase — riser count, riser height, going, total run, and pitch — checked against IRC R311.7, NBC 9.8, and Approved Document K.
Trade Calculation Guides
How-to guides for electricians, HVAC technicians, plumbers, and construction pros — with the NEC, ASHRAE, UPC, and IRC references behind each calculation.
· FieldDojo Team · electricalResidential Electrical Load Calculation: NEC Article 220 Guide
How to calculate residential service load with the NEC Article 220 standard and optional methods — required for service sizing and permit applications.
· FieldDojo Team · hvacManual J Heat Load Calculation: HVAC Sizing Guide for Technicians
How to calculate heating and cooling loads using Manual J — the ACCA standard method. Covers the inputs, the math, and why rule-of-thumb sizing fails.
· FieldDojo Team · electricalConduit Fill Calculations: NEC Chapter 9 Guide for Electricians
How to calculate conduit fill correctly using NEC Chapter 9 tables — maximum fill percentages, wire area lookup, and common mistakes that fail inspection.
· FieldDojo Team · plumbingPipe Sizing for Plumbers: Water Supply, Drainage, and Gas Piping
How to size water supply pipes, drain/waste/vent systems, and gas piping correctly — with the IPC and NFPA 54 references behind each calculation.
· FieldDojo Team · constructionHow to Calculate Concrete for Footings, Slabs, and Columns
Step-by-step concrete volume calculations for common pours — footings, slabs, walls, and columns. Includes waste factor guidance and ordering tips.
· FieldDojo Team · hvacDuct Sizing for HVAC: The ASHRAE Equal Friction Method Explained
How to size supply and return ducts correctly using the equal friction method — the ASHRAE standard approach used by HVAC professionals.
· FieldDojo Team · electricalWire Sizing and Voltage Drop: What Every Electrician Needs to Know
A practical guide to NEC-compliant wire sizing and voltage drop calculations for residential and commercial work — with the exact formulas used in FieldDojo.