Construction Cost Estimating & Job Costing
Take off quantities, price labour, materials and equipment, build a bid with overhead, profit and contingency, then bill, forecast and measure job profit, all on one clinic project in 8 graded labs.
Trades & Local Services · 11 courses
Trades & local services courses
Tradespeople and local service companies win or lose money in the estimate: material takeoffs, labour hours, crew and equipment cost, minimum charges and route density. These 11 courses teach that maths on one realistic job or business per course, in a spreadsheet that checks every formula.
The trade maths courses cover electricians, plumbers, HVAC, carpentry, welding, machining, painting, landscaping and auto mechanics. The business courses run repair shops, car washes, laundromats and dry cleaners, roofing and solar installers, tree, pest, pool, window, pressure washing and junk removal services, movers, sign shops and equipment rental yards. Always follow your local codes and safety rules; the numbers are illustrative.
Courses in Trades & Local Services
Car Wash Business Economics: Throughput, Memberships & Cost per Wash
Run an express tunnel wash by the numbers: cars per hour and utilisation, package mix and average ticket, cost per wash, unlimited club economics and churn, membership mix scenarios, rain-day effects, equipment payback, NPV and IRR, and a monthly dashboard – 8 graded labs on a fictional wash.
Plumbing Trade Math: Pipe Offsets, Slope, Flow & Fixture Units
Tape fractions and millimetres, 45° and rolling offsets, drain fall and grade, pipe volume and water weight, Q = V × A, fixture unit sizing, water heater first-hour rating and a job quote with a chart: 8 graded labs for apprentices and DIY planners.
Machinist Shop Math: Speeds & Feeds, Tolerances, Bolt Circles & Tapers
Inch/mm and fraction conversions, spindle RPM from SFM and m/min, feed rates and cut times, limits and fits with PASS/FAIL, bolt circle coordinates with SIN and COS, tapers with ATAN, drill point depth, sine bar stacks and a job quote with charts: 8 graded labs for apprentices and CNC learners.
Electrician Math: Ohm's Law, Load Calculations, Voltage Drop & Conduit Fill
Ohm's law and the power wheel, series and parallel circuits, single- and three-phase power with √3 and power factor, a dwelling load calculation with demand factors, conductor sizing with temperature and bundling factors, voltage drop with a 3 % size pick, conduit and box fill, and motor overload and breaker sizing with a chart: 8 graded labs for apprentices and license-exam practice. Illustrative tables, not affiliated with NFPA or any code body; your local code applies.
HVAC Math: Heat Loads, BTU, CFM, Duct Sizing & Refrigeration Basics
Convert BTU/h, tons, kW and °F/°C, calculate conduction and infiltration loads, sum a room-by-room load to size equipment, split 400 CFM per ton over the rooms, size round ducts by velocity, check superheat and subcooling against targets and compare SEER, EER and COP with an operating-cost chart: 8 graded labs for HVAC apprentices and exam practice. Illustrative tables, not copied from Manual J or ASHRAE; your local code and manufacturer data apply; not affiliated with any trade association.
Carpentry Math: Board Feet, Rafters, Stairs, Framing & Material Takeoffs
Read decimal feet as feet, inches and 16ths, price lumber by the board foot, count studs, plates and headers, find rafter lengths with Pythagoras and pitch angles with ATAN, lay out stairs against code-style limits, order sheet goods and decking with waste and fasteners, and price the job with markup and a chart: 8 graded labs for apprentices, builders and serious DIYers. Illustrative values; your local building code applies.
Welding & Fabrication Math: Weld Volume, Filler Metal, Heat Input & Cutting Layouts
Weigh plates and bar from dimensions and density, calculate fillet and groove weld areas, weld metal volume and deposited weight, filler metal with deposition efficiency, heat input in kJ/in with a WPS check, arc time and cost per joint, saw cut lists with kerf and remnants, and a full job cost with a chart: 8 graded labs for welders, fabricators and estimators. Illustrative values; follow the applicable welding code and safety rules. Not affiliated with any welding society.
Laundromat Economics: Turns per Day, Utilities per Cycle, Pricing & Payback
Run a self-service laundromat by the numbers: machine turns, revenue per machine and per square foot, utility cost per cycle, size-based pricing and payment costs, wash-dry-fold margins, equipment financing, Saturday peak capacity and valuation at a cash-flow multiple – 8 graded labs on a fictional store.
Landscaping Math: Areas, Mulch & Soil Volumes, Pavers, Plant Spacing & Job Quotes
Measure irregular beds from rectangles, circles and triangles, turn depths into cubic yards, m³ and bags vs bulk, count pavers with cut waste and order base in tonnes, space plants on square and triangular grids, order sod and seed, set sprinkler run times from the precipitation rate, estimate crew hours and price a job with markup and a maintenance contract: 8 graded labs for landscapers, garden designers and serious DIYers. Illustrative prices; supplier and local data apply.
Auto Mechanic Math: Displacement, Compression Ratio, Gear Ratios, Tyre Sizes & Labour Quotes
Engine displacement in cc, litres and cubic inches, compression ratio and a head-milling what-if, horsepower and torque with a dyno chart, gear ratios to road speed, tyre codes and speedometer error, mpg ↔ L/100 km and fuel cost, brake and tyre wear limits with conditional formatting, and a full repair quote: 8 graded labs for apprentices and service advisers.
Guides with worked examples
Board Feet Formula: How to Calculate Board Feet
Board feet formula with examples: thickness × width × length ÷ 12, nominal sizes, a lumber list in Excel, price per MBF and the order total with tax.
Engine Displacement Formula: cc, Liters and Cubic Inches
The engine displacement formula from bore, stroke and cylinders in cc, liters and cubic inches, plus compression ratio and overbore. Worked Excel example.
Markup vs Margin: Formulas, Conversion Table, Example
Markup vs margin explained: both formulas, how to convert one into the other, a price from a target margin and a conversion table, in an Excel example.
Frequently asked questions
Do I need to be good at maths?
No. Each task gives a hint and the coach explains common mistakes, so you build the formulas one step at a time.
Do the courses replace a licence or code book?
No. They teach the calculations and the business side. Always follow local codes, manufacturer instructions and safety rules.
Can I use the sheets to quote real jobs?
Yes. The labs build pricing and takeoff methods you can reuse with your own rates and materials.
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