Grano

[parksy]

Hi All
I am about to lay a screed which will be about 20mm-30mm deep. Because if is less than 50mm I understand that I can't use standard screed but will need to use 6:1:2 (grano:building sand:cement).

Does anyone know how to work out the amount of grano/sand/cement needed? Can I just take the grano volume as the final volume? Does anyone have a ballpark for number of 25kg bags of materials needed to produce 1 metre cubed for example?

Thanks for any help.
Chris

 

[noseall]

the mix will need to be, 2 parts granite, 2 parts sharp or screed sand and 1 part cement. you will still need a fairly dry "screeders mix" but it will dry rock hard.

what size is the floor you are screeding?

 

[parksy]

Hi Noseall.
Thanks for your correction.

The area is 2.7m x 4.2m and the screed will be between 20mm and 30mm so I will need a volume of about 0.3metres cubed.

When you say granite - is that 6mm granite chips?

Chris

 

[noseall]

you will need; 6, no. 25kg's of cement.
12, no. 25kg's chippings. (6mm chippings)
12, no. 25 kg's sharp sand. (screed sand, grit sand etc.)

 

[parksy]

Thanks Noseall - you're a star!
Chris

 

[parksy]

Hi Noseall

Just wanted to thank you for your advice. Your quantities were spot on and the screed went down well - although it was hard work. I would advise anyone else doing the same to definteily have two of you as it makes leveling it off so much easier.

The advice from everyone on here concerning thin screeds and grano was invaluable though. Thanks again

Chris