Slab over block and beam

[jayc89]

For a multitude of reasons I've ended up with a small section of the house with the block and beam subfloor still exposed. It's 160mm below final floor level, with the initial plan to install 100mm PIR and 60mm Cemfloor screed.

 

Can anyone see any problem if I was to replace the Cemfloor with a sand and cement screed that I can hand mix myself? I could even drop to 75mm PIR and increase the S+C screed to 85mm? Appreciate this is not something anyone would ever spec - the space is only to be used as a pantry and w/c so it doesn't need to be ultra-efficient.

[nod]

You will be fine with 60 mil S&C 

 

[jayc89]

I've started to prep the area and noticed gaps between the beams and blocks. It was previously grouted by the builder who fitted it but I guess some has come loose.

 

Should I attempt to re-grout it? What's the best approach; wet it again and then brush over a dry sand/cement mix?

[markc]

Just now, jayc89 said:

I've started to prep the area and noticed gaps between the beams and blocks. It was previously grouted by the builder who fitted it but I guess some has come loose.

 

Should I attempt to re-grout it? What's the best approach; wet it again and then brush over a dry sand/cement mix?

I’m guessing these are narrow gaps? More that likely everything just settling down and bedding. Nothing to worry about, you can brush some sand/cement around if you feel the need to.

[jayc89]

Just now, markc said:

I’m guessing these are narrow gaps? More that likely everything just settling down and bedding. Nothing to worry about, you can brush some sand/cement around if you feel the need to.

 

Yep, no blocks are loose when walking on it, just gaps showing between the beam and blocks. I'll brush some around before laying the DPM, just to be sure.