Replacement of Concrete Floor In Kitchen

[tlawrence127]

Hi all,

I have just bought a 1930s house. We are doing the Kitchen at the moment and I have discovered that the floor is all cracked and loose.
I have decided to replace the floor with a new concrete slab (with DPM & 50mm insulation).
Before I bought the house I noticed the Lino in the Kitchen was all out of shape. The previous owner told me they had had a leak but it was all sorted now.
When digging out the floor I noticed that around the water pipe was newer conrete than the rest of the room. My guess is that there was a water main leak and a new one has been fed in using a trench & pneumatic mole method (Would anyone agree). The old floor was therefore subject to heave as the soil expanded with the water.

Anyway My guess is that this was a couple of years ago. The soil under the existing slab is still very soft (I was able to insert a broom handle in over 2ft by hand) although it does feel firm to walk on.
My question is can I put my hardcore base on top of this soil (ie will it support the slab) or do I need to dig all the soil out down to the harder stuff? If I do then I have a hell of a job ahead of me!!!

Thanks,

Tim

 

[r896neo]

Your not going to like the answers and i think you know what you should do already. Sorry.

 

[joe-90]

Make a suspended timber floor. You can always change it in later years if you want.

 

[tlawrence127]

Make a suspended timber floor. You can always change it in later years if you want.

This is what I was thinking but reading the building regs it looks like I would still need concrete underneath. Do you think this is so? The span is 3M, would I need something in the middle to rest the joists on?

 

[r896neo]

You still need concrete as oversite but it is not structural so you can even put it on slightly dodgy ground really. as for the 3m span that is nothing but Do you have solid walls on both sides to run the joists into?

 

[tlawrence127]

yes, Red Brick walls each side and there is a row of bricks all the way round (part of the footings). Will 1 brick width be enough to bear the load of the floor or should I cut out part of the wall as well?