Buying a 10yo home FSBO, owner was the builder. Owner says the wavy floor on the 2nd storey is from the roof not being on before they did the 2nd storey subfloor (OSB, 2000sqft) and several rainstorms damaging the subfloor.
It is probably up/down waves of 3/4"+ across several rooms... so it is a general problem.
It is finished in $10/sqft brazillian walnut (!? = $20k I. Brazillian walnut over wavy floors... ugh).
BUT looking closer the sags are not in the 16" between joist spacing, but both directions and 3 or 4 feet between "peaks". Wife is BENT on buying this house. Why would these floors be so wavy? No visible foundation settling evidence (no drywall cracks, etc).
I first believed the owners story, but seeing the dips are not fitting in the space between joists... I am suspicious.
Votes for any of the following reasons?
Shoddy joist install where they are not level and square to each other? (Note, first floor is level)
Termites? (Note, first floor is level, no bounce in the floor is felt and no visible evidence, but we are in a termite area)
The owners story of weathered 2nd storey decking?
We are still in our inspection period. Who do we have look at it to say one way or the other?