Sloping concrete kitchen floor, surrounded by level floorboard and joist floor. Help!

[o0Poindexter0o]

Hi
I have an Edwardian end of terrace house that has a concrete floor in part of the kitchen and floorboards in the other part. The big problem is the concrete floor slopes massively and is going to cause problems when we take a non load bearing stud wall down, to make a kitchen diner and want a consistent floor covering all the way through. Not a hump in the middle of the floor. The area affected is approx 3.2m x 1.9m.

Please see attached photos of how much the floor slopes. We are talking 30 mm + over a 3.2m length.

Should i dig out the concrete floor and get it replaced with joists? or dig so far down and level it?

I would prefer joists as it will allow for better pipe and cable runs instead of the tortured path they now take.

If I opt for new joists would I need extra ventilation? there is a 450mm-600mm void under the rest of the ground floor so I would dig down to that.

Any advice, either pros and cons of each method would be greatly appreciated.

The images are:

Level(ish) wooden floor, then 2 of concrete floor (un)level, then floor diagram.


The Blue area is the concrete floor, the rest is floorboards. I suspect there was a stud wall on the right hand side of the blue area and there is defiantly a stud partition on the left, which is coming out.



Thanks

 

[o0Poindexter0o]

Any ideas please.

 

[Doggit]

Sorry, but you haven't made it very clear exactly which way the floor slopes. Can you redo the plan to show the direction of the fall.

In essence though, if you want the floor level, then yes, take down the concrete so that it clears the new joists (so not necessary to take it right down) and then level the floor over it's entirety.

 

[o0Poindexter0o]

Can you redo the plan to show the direction of the fall.

Hi
Thanks for responding. The high section is at the bottom of the plan and slopes downward as it heads to the top of the plan.

 

[Doggit]

Is there a drop on the wooden floor as well then, or only the wooden floor Has there been any subsidence as 30mm is a lot to drop.

 

[o0Poindexter0o]

Wooden floor level (as one of the pics show), seems to have been poor application of concrete!

There is a door to the outside on that wall and it just seems to slope down from there.

 

[Doggit]

Then as I suggested earlier, just take out as much concrete as necessary to get the joists in, and level the floor right across. If one side is still lower, then you can sister 4x2s alongside the existing joists to bring the height up.