I am renovating an 117-year old house that has a sturdy but unsalvagable 3-inch plank pine floor in the kitchen (the boards are approx 3/4 inch thick); the pine is over an additional wooden underlayment (so at least an inch thick...). Due to the fact that hundreds of nails were driven into the floor to hold an old vinyl tile bed I don't think refinishing is an option. My question is(although normally not recommended), with the sturdiness of this floor (NO bounce at all!), could I just use this as my substrate for new ceramic tile without having to mess with backerboard? Thanks in advance!!