For example you would say:
Miles and miles of road
Tons and tons of food
How about when referring to the floor inside a house (given that the house is relatively big)?
[...] and [...] of plywood floor
You would say:
Because floorage is an areal measure.
(Text rescued from potentially ephemeral comments.)
Because I couldn’t see how the asker’s two exemplars of tons of food and miles of road made any literal (read: “literal-literal” as opposed to hyperbolic) sense in the case of your run-of-the-mill single-family home, I chose the answer that seemed best-matched to those two in scope and tenor.
For rather unlike scenarios, compare these two scenarios:
In the US, people will often refer to large amounts of "square footage"; as in "this apartment is huge! You have a lot of open square footage".
Here are two terms for the area of a floor, in particular:
If you really want to say plywood floor, then do so, but there is no special term for expressing the amount of floor space (area) - no more than for your tons and tons of food. You can say acres and acres of plywood floor, but there is nothing special about acre in this regard.
There are lots of different units of area, including "square" followed by any unit of length - square lightyears, for example.
If you are referring to a room or the rooms of a single apartment or house, I think the most common measure is square feet or square meters according to the metrical system you are using.
If you want to emphasise the unusually large measure of the floor space you may use the expression thousands and thousands of square ( feet/meters).