Word that refers to the "quantity/amount" of floor?

You would say:

Acres and acres of plywood floor

Because floorage is an areal measure.

Afternote

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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:

1. Do you new give homeowners a per-square-foot pricing break for hardwood flooring installations above a certain square footage?

2. Wow dude, you’ve got like acres and acres of hardwood floors here hidden under your wall-to-wall carpeting!

   Don’t bother stopping at the grocery store: we’ve got tons of food here.

   Gosh, your driveway is like miles long!

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".