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Greenhouse base on soil - easy option


Hopefully you can help me as this is my first post.

We have a green house - aluminium with glass.  Size 3.8 meter by 2.5 meter.

Greenhouse is currently on bricks but few of the bricks are broken and it seems it is not being used for years as we have recently moved in this house.  Greenhouse is in good condition and I wanted to make good use of it.

My plan is to move this to other side of the garden where we have more sun and it will also make space for kids. 


I am not expert so cannot create a brick based base so looking for easy options

Could some one help me with step by step guide how to build base in soil and what material would be required and where to buy?

Thanks again for any help.



  • BobTheGardenerBobTheGardener Posts: 11,391

    You can place them on compacted soil but it must have a metal base (often called a plinth) fitted, or it will warp as the ground moves and the glass will crack.  See here:



    A trowel in the hand is worth a thousand lost under a bush.
  • mane jimane ji Posts: 10

    Thanks for the link.

    My greenhouse is over 10 feet so may not be suitable for compacted soil.

    Is it easy to put softwood sleepers as they are available in local timber yard?

    Oak sleepers are quite expensive.



  • ShepsSheps Posts: 1,711


    You could try some of these interlocking plastic grids, they are quite cheap and easy to lay on a flat surface, once level you can fill them with gravel to add weight and stop them from moving.

    Not sure if your greenhouse has a specific base, but I guess you would need one, or you could just use some ply wood.






  • WillsWills Posts: 262
    If your green house is going on a level base you could try 4 bags of sharp sand to 1bag of cement do a dry mix lay paving slabs water and leave mix will set it a few days.
  • mane jimane ji Posts: 10










    Please see above pics:


    I am just wondering what if I use breeze blocks but there are many types of blocks.  Which one should I use and what should be the mix of sand of cement?


  • mane jimane ji Posts: 10

    any help

  • Steve 309Steve 309 Posts: 2,753

    That's a good sized greenhouse image

    I'm no expert on building, but I'd think that a 4:1 or 5:1 mix of sand & cement would do as mortar for breeze blocks - I'm sure there's a website that'd tell you.  And what sort of blocks.  They don't have to support an enormous weight so maybe the cheapest would do.  I think I'd have some sort of foundation though - maybe a rectangle of slabs laid on sand would be enough.

    However you decide to build it, do make sure you have some soil beds inside.  I've worked in a greenhouse where everything had to be grown in pots and it was very frustrating,

  • mane jimane ji Posts: 10

    Could I drill directly into the block?

  • Steve 309Steve 309 Posts: 2,753

    I don't know enough about it - best to wait for an expert,  But as a DIYer, what I'd do in your position is this:

    • prepare the soil where the greenhouse beds will be (and cover them to prevent damage)
    • dig a shallow trench where the walls will be and either fill it with concrete (about 6" depth should be enough) or a layer of sand and some paving slabs
    • lay one or two courses of blocks (leaving a gap for the door, of course!)
    • drill into the tops of the blocks for the frame
    • lay a rubber or similar gasket all round to allow for a little movement
    • use small expansion bolts through the frame and rubber into the blocks
    • put the glass back in.
    • uncover the beds and plant them

    Good luck!

  • mane jimane ji Posts: 10

    okay thanks...

    i may do dry sand and cement underneath the trench and then pointing between the breeze blocks.



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