Tape measures don't read in decimal. My staff rarely can convert them into decimals without a calculator. A lot more power could be leveraged within goCanvas if fractions could be entered and used in calculations.
I've worked around this by creating a fraction chart and using it as a reference image in a drawing field. Unfortunately, when the team member closes the drawing and tries to remember that the piece of material that he/she needs is 12.875" x 32.75", it results in a lot of torn cardboard pieces with measurements coming back to the office with the inevitable, "this goes with Mrs. Smith's Canvas doc"
In most construction, going to 16ths would be fine, but I'm sure someone out there is building a deck like a watch and would like 32nds or 64ths.