We are planning to put carpet over an oldish hardwood floor. I noticed that the floor has a dip of about 3/8" in a few areas. I intend to measure around with a long straightedge and see if I can find any worse spots.
The dips are about 6" across by 3-4 feet in length (coincide with a once-removed wall). There's no structural issue underneath (basement) so I'm only concerned about the effect on the carpet - how it looks, wears, and avoiding a trip hazard.
Is this size dip bad enough to do something about? If not, what is generally considered to be the maximum allowed variation in the floor?
(If it is enough of a problem, I intend to fill with strips of 1/8 or 1/4 hardboard or plywood or similar.)