How-To Guides
Practical guides with formulas, code requirements, and worked examples.
Electricians
Electrical Conduit Bending Basics: Offsets, Kicks, and Saddles
How to calculate and execute common conduit bends — 90° bends, offset bends, kick bends, and saddle bends. Covers multipliers, shrink values, and layout techniques.
Copper vs Aluminum Conductors: When to Use Each
A practical comparison of copper and aluminum electrical conductors. Covers ampacity differences, cost trade-offs, connection requirements, and when aluminum makes sense.
Electrical Grounding and Bonding Basics
Understand grounding vs bonding, equipment grounding conductors, grounding electrode systems, and bonding jumpers per NEC Article 250.
GFCI vs AFCI Protection Requirements Under NEC
Understanding when GFCI vs AFCI protection is required, NEC changes in 2023/2026, and how to pass inspection.
How to Size Electrical Wire for Branch Circuits
Step-by-step guide to selecting the correct wire gauge for residential and commercial branch circuits using NEC Tables 310.16 and 310.17, including derating for temperature and bundling.
Motor Circuit Sizing: Wire, Overload, and Branch Protection
Size wire, overload protection, and branch circuit protection for motors using NEC Article 430, FLA, FLC, and the 125% rule.
NEC Box Fill Requirements: How to Size Electrical Boxes
How to calculate box fill per NEC 314.16. Covers volume allowances for conductors, devices, clamps, and grounding conductors with worked examples.
NEC Conduit Fill Requirements: How to Calculate Conduit Size
How to calculate conduit fill percentage per NEC Chapter 9, Table 1. Covers the 40% rule, conductor area calculations, and common conduit sizing scenarios.
Ohm's Law Basics for Electricians: V = IR and Beyond
A practical guide to Ohm's Law and power calculations for working electricians. Covers V=IR, P=VI, troubleshooting applications, and single-phase vs three-phase relationships.
Residential Electrical Load Calculations Per NEC Article 220
Calculate residential service load using standard and optional methods, apply demand factors, and determine service size requirements.
Managing Voltage Drop on Long Circuit Runs
Calculate voltage drop, understand 3% vs 5% limits, and apply practical wire upsizing strategies per NEC 210.19.
Carpenters & Framers
How to Calculate Compound Miter and Bevel Angles for Crown Molding
Calculate precise compound miter angles for crown molding, hip trim, and valley cuts on angled surfaces.
Deck Joist Sizing and Spacing Per IRC
IRC span tables and spacing requirements for deck joists by species, size, and load conditions.
How to Calculate Rafter Length and Layout
Step-by-step guide to calculating common rafter length from roof pitch and building span. Covers the math, bird's mouth cuts, ridge deduction, and overhang calculations.
How to Design a Staircase: IRC Code Requirements and Layout
Complete guide to staircase design for residential construction. Covers IRC riser and tread requirements, total rise measurement, stringer calculations, and common layout mistakes.
How to Estimate Drywall: Calculating Sheets, Mud, and Tape
A practical guide to estimating drywall quantities for residential and commercial projects. Covers sheet count, waste factors, joint compound, tape, and fasteners.
How to Layout Framing Walls: Studs, Headers, and Cripples
Step-by-step wall framing layout including 16 vs 24 OC spacing, king studs, jacks, headers, and practical sequencing.
Plywood and OSB Subflooring: Selection and Installation
Subfloor panel selection, span ratings, fastener schedules, glue-nail method, and edge details per IRC.
How to Lay Out and Cut Rafter Birdsmouth Joints
Birdsmouth joint layout, HAP calculation, depth limits, IRC compliance, and marking techniques with speed square.
Pipefitters
Brazing vs Soldering Copper Pipe: When and How
When to braze versus solder copper pipe connections. Covers temperature ratings, filler metals, joint preparation, and code requirements for potable water and medical gas.
Parallel Pipe Cutback Calculations for Multi-Line Offsets
How to calculate cutback dimensions when multiple parallel pipes need to offset together. Covers the geometry, formulas, and common spacing scenarios.
Pipe Thread Types and Sizing: NPT, NPS, and BSPT Explained
Complete guide to NPT, NPS, and BSPT thread types, nominal vs actual pipe dimensions, schedule ratings, and thread engagement requirements for proper fitting selection.
Rolling Offset Calculations: The Complete Guide for Pipefitters
How to calculate rolling offsets when pipe needs to move both vertically and horizontally. Covers the true offset formula, travel calculation, and fitting rotation angles.
Steam Pipe Sizing Basics: Pressure, Pitch, and EDR
How to size steam distribution piping for low-pressure heating systems. Covers steam velocity limits, condensate return requirements, pitch, and sizing by equivalent direct radiation.
Structural
Concrete Footing Sizing: IRC Calculations and Soil Bearing
How to size concrete footings per IRC requirements. Covers soil bearing capacity, footing width calculations, depth requirements, frost line, and stepped footings.
Deck Beam and Post Sizing: A Builder's Guide
How to size deck beams, posts, and footings for residential decks per IRC requirements. Covers span tables, tributary area, and common deck framing configurations.
Header Sizing for Windows and Doors: What You Need to Know
How to size headers for window and door openings in residential framing. Covers IRC span tables, load paths, and when engineered headers (LVL) are required.
How to Size Floor Joists: Span Tables and Load Calculations
A practical guide to selecting floor joist sizes using AWC/NDS span tables. Covers species, grade, spacing, load requirements, and when to consult an engineer.
Roof Truss vs Stick Framing: Spans, Cost, and Engineering
Comparison of roof trusses versus conventional stick framing. Covers span capabilities, cost analysis, engineering requirements, and when each method is appropriate.