Rules of thumb for steel design. Consider a beam spanning 30 feet supporting a 10 foot width of floor with a total supported load of psf. The time of localized, fractured and siloed product development is coming to an end. Oem2 Electrode Humidifiers Technical Documentation. Design by rule of thumb Thank you Ajuk. The brighter the color of your architect's socks, the higher chance you have of being asked to frame something totally beyond the laws of statics. Use commonly available size of bars and spirals. For preliminary design use square columns. For large project Max area in pour: Use single-sided connections, shear tabs, or single angles wherever possible.