Home & workshop
How much concrete, paint, tile or cable the job takes, and what the wiring behind it has to carry.
Two questions a job actually turns on, and this is where they get answered: how much of the material to buy, and whether the wiring behind it can carry what you are about to plug into it. The quantity tools round up and say so — concrete comes in bags and tiles come in boxes, and an answer of 11.3 boxes is not an answer you can take to a merchant.
Quantities, electrics, and the weather
Quantities: concrete, gravel, sand and mulch, paint, tile, flooring and wallpaper, fencing, stairs, roof pitch, pool volume and room area. Give them a dimension and they hand back something you can order, with the waste allowance the trade normally adds already in it. The workshop set — board foot, drill size, metric thread and screw spacing — is the same idea at bench scale, where being out by a millimetre costs you the piece.
Electrics: voltage drop and cable sizing is the one to run before a long outdoor run, because that is where undersized cable hides. Power, kWh cost, resistor colour codes, capacitors, voltage dividers, RC time constants, battery life and solar storage cover the rest. The weather set — dew point, wind chill and heat index — is here because they decide whether you can paint, pour or work outside today, which makes them a scheduling question rather than a meteorological one.