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Construction Master 5

Feet-Inch-Fraction Construction-Math Calculator in English or Spanish

The Construction Master 5 is the essential tool for serious building professionals. Easy-to-use in the field or office it meets the need for fast, accurate construction- math solutions. Enter the numbers, just as you would say them and the solutions appear in an instant – they’re built-in to your Construction Master 5. Ideal for plans, and layouts. Reduce the risk of expensive errors when estimating costs and materials. Save time, money and frustration!

For Contractors, Builders, Architects, Engineers and Tradespersons

Model #4050


Suggested Retail: $69.95 ---


Para esta página en español, haga clic aquí por favor



  • Linear, Area and Volume solutions: convert dimensions, including Metric
  • Rafter, Roof and Framing solutions: Hip/Valley, Jacks and Rake-Walls
  • Stair solutions: Risers, Treads, Stringer, Incline
  • Built-in Right-Angle solutions: Automatic Square-ups
  • Circular and Arc: Areas, Diameters,
  • Circumference
  • Board Feet
  • Weight per Volume

Dimensional Math and Conversions

  • Works in and converts between building dimensional formats: Yards, Feet-Inch-Fractions, Decimal Feet-Inches and Metric – including Area and Volume
  • Find Weight per Volume

Added Features

  • User Preferences: Set custom defined options such as Fractional settings for 1/2, 1/4, 1/8, 1/16, 1/32, and 1/64
  • Backspace Key: Makes it easy to change just-entered values
  • Cost per Unit: Easily solve unit costing and pricing
  • "Paperless" Tape: Allows for review of last 20 entries; double- check totals
  • Standard Calculations: Works as a math calculator with +, -, +/-, x, ÷, %, Π, 1/x, X2, and √.
  • Automatic Shut-Off saves battery life


  • LCD in Spanish
  • Function Keys in Spanish
  • User’s Guide in Spanish

Dedicated Functions

  • Stair calculations for Risers, Treads, Stringer Length and Incline Angle; displays Run and Rise
  • Custom Rafter Function provides Common Rafters, Regular and Irregular Hips, Valleys and Jacks. Jack Rafter feature provides complete solutions for Regular and Irregular Pitch roofs. Displays On-center spacing
  • Solutions for Circles, Arcs, Columns, Pillars, Windows, Post-holes and more
  • Rake-Wall function determines Stud Length for
    any On-center Spacing, in Ascending or Descending order
  • Board Feet Lumber estimating


  • Protective 360° Hard Cover Door
    Easy-to-follow Pocket User’s Guides in English and Spanish
    Long-Life Battery
    Full One-Year Limited Warranty
    English and Spanish CD-ROM with “How-To” Video and User’s Guide

Tech Specs

  • Size: 5.7” x 3.0” x 0.65” (145mm x 76mm x 17mm)
  • Product Weight:
    4.15 oz. (117.7 gm)
    Includes Case and Pocket Reference Guide
  • Power:
    One 3-volt (CR-2016) Long-life Battery
  • Display Type:
    LCD: 11 Digits (7 normal, 4 Fractions) with Full Annunciators
  • Display Dimensions:
    0.73” x 2.56” (19 mm x 65 mm)
  • Accuracy:
    10 Digit Internal Accuracy