HELP! Can you use building sand mix with cement to relevel

[Nathan2015]

Ive just had a 5m by 5m concrete base laid in the back garden for a log cabin the bloke came back yesterday to remove the wooden frame and discovered that one corner is about 2 to 3 cm lower so he has releveled but he used building sand he had left over in his van mixed with cement will it be ok or shall I tell him to rip it up and redo it please advise me


Many thanks
Nathan

 

[jeds]

Do you mean redo the levelling or redo the slab? 2-3cm out of level over 5m isn't brilliant but it's not going to majorly affect your building.

 

[^woody^]

Building sand is soft sand, and when used in large areas will crack and will suffer from frost attack.

If it will be covered, it will be OK. If exposed, have it re-done with a sharp sand or concrete sand.

 

[Nathan2015]

It is just one corner of the base just about 3feet each side that has been releveled.
I would ask him to redo the corner that he has releveled with concreat sand its solid but I'm just a bit worried about if soaking up water and crumbling later on.

 

[jeds]

Thin layers of sand cement aren't usually durable. A levelling compound would have been better. At 3cm thick you would need to add sand to bulk it out.

 

[theprinceofdarkness]

Building sand is not a type of sand. You could use the term to differentiate it from sandpit sand. Sharp sand is adequate for the leveling job, soft sand is not. The surface should be primed first as layer is so thin.
Frank