What Is Under Your Arkansas Floor: Plywood, Plank or Slab
The substrate decides more about your flooring quote than the flooring does, and identifying it takes five minutes.
Three substrates
Plywood or OSB over joists
The standard from roughly the 1970s on, which covers most Arkansas housing — Conway, Jonesboro, Springdale, Rogers, Bentonville and the newer half of everywhere else. Lift a floor register: plywood shows thin layers at the cut edge, OSB shows compressed chips. It takes every material on this site.
Plank decking
Boards laid across the joists, found in prewar housing — the older parts of Pine Bluff, Fort Smith, Little Rock and North Little Rock. At a vent you will see individual boards with gaps between them rather than a continuous sheet. It takes nailed solid hardwood and carpet directly. Tile, vinyl and laminate want an underlayment or a plywood overlay first, because the gaps telegraph and the boards move independently.
Concrete slab
Common in postwar and modern construction. Tap it — a slab sounds dead, a framed floor sounds hollow. It takes tile, stone, rigid-core vinyl and engineered wood well, and solid hardwood not at all.
What each one adds to the quote
- Plywood or OSB — usually nothing. This is the easy case.
- Plank — an underlayment at roughly a dollar a square foot, or a plywood overlay at two to four, which also costs height at doors and at the bottom stair riser.
- Slab — grinding and levelling where it is not flat, which varies enormously.
This is why two quotes for the same material in the same city can differ so much: one installer has looked underneath and priced the preparation, the other has not.
The five-minute check
- Lift a floor register and look at the cut edge.
- Walk the room barefoot and feel for give.
- Whether there is a crawl space or slab beneath tells you most of it.
- Tell the installer what you found before they quote.
Common questions
How do I know if my floor is a slab?
Drop something heavy-ish on it — a slab sounds dead. Whether there is a crawl space underneath answers it directly.
Can I tile straight onto plank decking?
Not directly. It wants a plywood overlay and usually an uncoupling membrane, plus a deflection check first.
Does the subfloor change what is possible, or just what it costs?
Both, and the cost side is the one people underestimate.