Dip in floor

[Bewdy]

I'm about to refit my bathroom and something I have noticed is that the floor in there is very unlevel. It seems there is a sag/dip in the floor, generally running to the centre of the room, which in parts seem to be out by almost an inch. I have attached some pictures.

http://1drv.ms/1GCTDWC

My query is how best to tackle this. Assuming that perhaps the floor has sagged naturally over time and under it's own weight, I'm a little concerned about adding more weight by the use of floor leveling compound and making things worse.

My initial thought was to take the floorboards up and perhaps add new level battens to the side of the floor joists, and smooth the floor out this way.

What does everyone else think?

Suggestions would be welcome.

 

[Burnerman]

That is one hell of a dip
Assuming this is on the first floor, has a supporting wall below been removed in the past, do you know?
John

 

[Burnerman]

Sorry, dual post

 

[Bewdy]

That is one hell of a dip
Assuming this is on the first floor, has a supporting wall below been removed in the past, do you know?
John

I don't think so, and there's no visible sagging in the ceiling below. Curiously the bottom of the dip appears to be right in the middle of the room. If it was due to a supporting wall missing I would have thought the sag would have been a bit more one directional?

I can't put a support below any how, so I need other remedial advice.

 

[Burnerman]

For the life of me I can't see why there is such a sag as this....either the joists are undersized or there has been a supporting wall there at some time. Even more so as the ceiling below seems unaffected.
I can only suggest lifting up whats there and having a look - but I'd welcome input from the others!
John

 

[bernardgreen]

Is there any possibility that a previous owner had set up the floor to be a wet room with the drain, now covered over, in the middle of the room?

 

[Burnerman]

Good thinking Bernard.....surely can't be anything else?
John