How much sand - 4 inch blocks on side

68508224

Building a garage with cavity walls, about 2000 blocks in total. Can anyone advise about how much sand would be needed? Standard 4 inch blocks on their side. Thanks for any help.

xDerp

Back of the envelope!

10mm mortar bed around the block +10mm and 100mm thick, bed and perp joints so you have 2000*(0.45+0.225)*0.01*0.1

That's 1.35m^3 of mortar

But you might have 4:1 sand - cement.

Cement gets in between the sand so it's hard to say the contribution to the overall volume. 20% max but likely only about 10% to the whole lot. There's air entrainment from the plasticisers but not sure how much that would contribute.

Maybe 1.2 ish m^3 of sand

Sand is somwhere from 1.6 - 2 ton per m^3 (from internets), say 1.8

Somewhere around 2.2 ton?

68508224

I won't pretend to have followed the maths but thanks a million! Hadn't a clue 👍

mr.stonewall

Don't forget the sand needed to plaster it as well

68508224

Actually on that, can the same sand be used for plastering or would it be advisable to get plastering sand?

bfclancy2

https://www.boards.ie/discussion/comment/120641329#Comment_120641329

Plastering sand would be sharper, i've laid blocks with plastering sand, no real issue, but the soft sand is easier to lay with