If one has warped or moved by 25mm leaving the floor sloping across 4 5 1350mm then the floor will be sitting above the two or three intermediate joists by a noticeable amount and thus be very springy as unsupported.
How to fix a warped floor joist.
Typically one end of the joists rests on an exterior foundation sill and the opposite end rests.
Warping manifests as gaps between the boards.
Setting the joists perfectly level at the house is easy and the beam makes them fairly even near the front edge but the problem is in the middle.
Even though we use 1 pt lumber the joists are often slightly warped or vary in depth at times causing adjacent joists to differ in height by as much as 1 2 inch or more.
How to straighten a warped floor.
If the floor is solid and does not move then it could be that the others are out too.
How to straighten warped floor joists.
Lets look over straightening joists in and existing home and hte property of installing underfloor insulation as we go.