Pardon me, but what does 4/4 mean?
Chances are the first time you stepped foot into a hardwood lumber dealer you saw all these crazy fractions flying at you: 4/4, 5/4, 6/4, 8/4 and so on.
They’re industry terms that not everyone knows right off the bat, but they refer to the thickness of the lumber you’re looking at.
Let’s start with the most common: 4/4. If we were talking you’d hear me say it as “four quarters,” which is short for four quarters of an inch. If you’re pretty snappy with numbers, you’ve already put together that 4/4 is equal to one inch. 
