Most people look at a shiny floor and think that the shine is the reason we finish (wax) floors.
Not true. Finish is an outer layer – the “hard chocolate outer shell” (with apologies to M and M’s) that protects the relatively soft under floor from abrasion / wear.
Thus we only actually need to finish floors that are either :
A) Soft – vinyl, wood, etc that are subject to being worn thru by constant foot traffic.
B) Porous – concrete that is subject to staining when spills penetrate thru the surface and discolor permanently. We sometimes seal (finish) grout lines on ceramic floors for the same reason.
While you don’t normally notice wear even on unfinished floors, it does eventually show. The most common example in the commercial cleaning business is a plant manager or security guard’s desk on a vinyl floor with no chair wheel protectors under the chair. Eventually the wheels will grind right thru the vinyl to the concrete sub floor below.
This would take many more years on a floor that wasn’t constantly abraded by wheels, but high traffic situations would eventually start to wear thru. Think of how many shoes with sand and grit in the soles go thru a Target or Wal – Mart store in a year for instance. Each of those is a little piece of sandpaper grinding off a little of the floor – or a little of the finish, if the floor is protected.
For the ultimate example google “Bernoulli” – Bernoulli’s principle was derived from observing wear patterns in (unfinished) stone stairways.
As an aside, I’ve been told – but haven’t seen the data – that an unfinished floor is MORE slippery than a finished floor. This makes sense – if you were a finish manufacturer (Johnson’s Wax is the biggest) you wouldn’t want to be selling a product that increases the liability for slip and fall liability suits.
When should you not finish the floor ?
When it doesn’t need it – ceramic floors, some sheet vinyls in low traffic situations that come with substantial factory finishes (medical exam rooms) and most types of stone floors (separate post)
In fact if you do atempt to finish most ceramic and stone floors you will usually be disappointed in the appearance – finishes in general do not adhere well to ceramic floors. They flake off – after a short period of time the floor looks like it has the aftermath of a bad sunburn – mottled with little white loose pieces of “skin” shedding.
Nobody ever gave me a straight answer on why this is – my two theories are that the ph of stone is a little different than the ph of vinyl so there is a chemical reaction that delaminates the finish and, alternatively, that the finishes are resilient (like vinyl) unlike ceramic – so that foot traffic compresses and decompresses the finish on top – but not the underlying ceramic, so they separate. Doesn’t really matter why tho – finish will separate from a ceramic floor, and you won’t get the appearance you would like.