NHBC claim for deflecting and creaking floors

[NiceCatExecutive]

I have an issue with floors in my new build (>5 years old).

I have raised a claim with NHBC regarding the deflection that is visible in some places, and the creaking that is quite extreme in these areas - primarily around a bay window and on the hallway landing.

I was asked to instruct a carpenter to produce a report, which explained that he believes that 600mm centres are too wide for chipboard floors on I joists.

The NHBC rejected this because there has to be damage for there to be a claim, and what I am experiencing doesn’t amount to any damage. I am concerned that the noise seems to be getting worse, and if there is no way to claim for this under the NHBC warranty then I will have to address this myself.

Has anyone here had any similar experiences?

[New Home Expert]

I'm assuming you are the second buyer otherwise you would have reported this issue straight away.
It is true the NHBC are only interested in "damage" after the first two years.

So the NHBC will only sort this if someone breaks a floor joist.

I must say having used these joists on many sites, I can't remember ever having them at 600mm centres.
It would cost the builder more as the joist would be deeper, and the house higher to give the required 2.3m clear per storey.

I suggest you check with Building Control, (no doubt also with the NHBC) to see if 600mm centres joists centres were passed.

Who was the housebuilder?