You might have had a recent survey where you have been told cavity wall insulation has blocked off your sub floor ventilation. You might have also been told you have drainage issues around the property that might put your floor timbers at risk of decay and woodworm.
The below video shows what happens when you have drainage issues and even blocked sub floor vents. Eventually you will get wet rot or dry rot in the suspended timber floor timbers. This can become very costly to fix.
I installed drying equipment into this floor to remove all the moisture, before timbers got replaced.
If you have dry rot issues, it is imperative to install drying equipment to remove the source of moisture rather than having the typical cover up job with a guarantee.