Sloping Block and beam floor.

[Clint101]

Hi
I have a block and beam floor on my extension its 9m in length and slopes 55mm from one side to the other, I dont think the builder knew that a spirit level existed..it will have 120mm insulation and ufh and a liquid screed to finish, is there a way I can level the block and beam prior to laying the insulation and screed? I did think maybe a sand/cement screed to get it back to level.
To cut a long story short the builder left part way through the build with at the very least £10,000 of our money and I am now left to do most of the work myself. Any suggestions would be much appreciated.

 

[noseall]

I have a block and beam floor on my extension its 9m in length

9m concrete floor beams! I bet they were hefty.

To cut a long story short the builder left part way through the build with at the very least £10,000 of our money

Your money? I'm guessing any base over 9m will cost double that, just to get out of the ground. I'd ask for £500 back for the extra screed needed to get the floor level.

 

[Notch7]

I have a block and beam floor on my extension its 9m in length and slopes 55mm from one side to the other

Before you do anything, I would use a laser level and check all the datum points.

For example how does the height of the beams compare to the finished floor level in your house - I presume you want a level floor from house to extension?

If you need say 100mm insulation, say 65mm of liquid screed and say 15mm for tiles and adhesive then you need 180mm min

You also need minimum 150mm clear space below the beams for air flow.

Have the telescopic vents been fitted correctly?

And secondly why are the floor beams not level? Usually floor beams sit on the inner skin of blockwork, which should be in line with the outside brickwork. Is your brickwork not level?


What stage is the build at?

If the infill blocks are in and the inner walls are done, you can’t easily move the beams

 

[^woody^]

Level the insulation and screed.

However, as the floor beams rely on the foundation walls for level, are you sure that foundations have not settled or are settling further?

 

[Clint101]

Thank you for your replys, the build was started in May 2021, in all honesty I'm not completely sure why it's so out..the shell and roof are all finished now..I'm starting to concentrate on the floor we are having 120mm insulation followed by ufh and 50mm liquid screed , I can visually see where the floor seems to dip in places, the structure seems sound, I just need to make up the difference for the insulation to sit level.
My thinking is to try and do a sand/cement screed from the 50 to 55mm deepest point then feather out, I just need to make sure the insulation is level as can be and flat.

 

[^woody^]

If you are having a liquid screed, then it will self-level. Just check with the supplier that the minimum thickness will be OK