[Closed] Damp - kitchen floor

Moved into the house 5.5 years ago, kitchen in decent condition so haven't done anything to it since we've been here. Kitchen has been pretty much untouched since the house was built in 1995. Over the last week we noticed the lino starting to bubble up in places, then we could feel the joins in the floorboards starting to lift. So today I've cut the lino near the kitchen units and peeled it back to see floorboards soaking wet and mouldy in places.

Something seems to have happened in the last week to cause it. Not sure if it's damp risen through or a burst pipe. To be honest I'm not great when it comes to building maintenance! But to my untrained eye the whole floor build looks a bit odd.

Any ideas? Photos upcoming.