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How much sand - 4 inch blocks on side

  • 25-05-2023 8:35am
    Registered Users Posts: 147 ✭✭

    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.


  • Registered Users Posts: 87 ✭✭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?

  • Registered Users Posts: 147 ✭✭68508224

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

  • Registered Users Posts: 1,730 ✭✭✭mr.stonewall

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

  • Registered Users Posts: 147 ✭✭68508224

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

  • Registered Users Posts: 173 ✭✭bfclancy2

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

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