From our Facebook Group:
My last inspection was a 2003 build. Both floors of bedrooms adjacent to each other—opposite sides of the house—had floors that creaked mercilessly—and focused primarily toward the walls that separated the two rooms.
The floor joists were dimensional lumber.
The roof consisted of trusses that spanned both rooms.
All in all, not a difficult fix to a very noisy condition.
I told my buyer I would be very surprised to not find that the bottom chord of the trusses had been nailed to the wall top plates resulting in the walls “hanging” from the trusses both due to truss uplift and shrinkage of the dimensional lumber floor joists. This was further supported by my being able to stick the end of my tape measure under the bottom plate of the wall.
I suspect the creaking floor was from movement on the nails through the wall bottom plate into the sub-floor. Very annoying to my clients and may have been a deal breaker.
I assured them it would not be a difficult fix – which would involve disconnecting the trusses from the wall top plate (un-nailing them).
Installation of the brackets that should have been installed in the first place can then be done. These brackets allow for the truss bottom chords to move up and down seasonally.
Because it is winter, and the trusses are likely in lift mode, this work should be done in the summer when the bottom chord is at its low point. Then the gap under the wall bottom plate can be properly supported and attached to the floor structure. All in all, not a difficult fix to a very noisy condition.
— Pro Inspectors (@TodaysInspector) December 1, 2016