Raising a concrete floor

[Garyn31]

I am looking to convert my downstairs cupboard space into a toilet area. The floor is lower than the joining room by approx 6".
What would be the best way to raise this by 6"?

Any suggestions welcomed.

 

[noseall]

polythene, insulation and concrete.

i would be more concerned about the toilet waste and extractor fan.

 

[Garyn31]

Thanks noseall,
What thickness would you recommend for each material?

 

[noseall]

because the area you are upgrading is so small (percentage wise) it probably doesn't require part L regs, so any amount of insulation will be a bonus.

fit membrane then 50mm polystyrene and 100mm trowel finished concrete.

 

[Garyn31]

Could you please confirm concrete mix?
I am thinking 4 parts sharp sand, 1 part cement!

 

[noseall]

Could you please confirm concrete mix?
I am thinking 4 parts sharp sand, 1 part cement!

you will need sand and gravel mixed (ballast) and mix it at a ratio of 6 parts ballast to 1 cement.