Shed base from MoT Type 1

Hi everyone,

Currently I'm digging out a section of lawn for my shed base. Will be 14ft x 10ft.

Soil is quite heavy clay soil.

Could a plastic shed base be installed directly on top of a compacted sub base such as MoT Type 1?

I like the semi permanent nature of those plastic shed bases and they supposedly have a high strength to weight ratio.

I was looking at viable alternatives to concrete, timber or slabs. None of which I particularly want to use.

Thanks,

Daz

MOT doesnt deal well with point loads and so the shed may gradually sink into it. Even a small 1ft x 1 ft spreader plate of some sort will be enough if you compact the MOT well. The plate would need to be plastic or masonary though so it didnt rot and then your back into flag territory.

If the base of the shed base if flat then it will be fine. but i doubt it is.

Hi R896neo,

Thanks for the reply. In that case, do you think the plastic base could go directly on the earth, with a damp-proof membrane underneath? Supposedly they can according to the various manufacturer websites but I'm not too convinced.

Either that or it will have to be concrete as timber will just rot quickly in my damp clay soil.

Same thing applies where the base has the floor joists etc that bit will point load the ground and gradually sink into it.

You'd certainly be much better with compacted mot than just earth.

If you want to go down this route I would prepare the area in mot and then when the base is delivered you can see exactly where the cross members are and rake out some mot and drop a flag in at those points.

To be honest a 14x10 shed is a pretty big brute and i would always recommend a concrete base for one that size.

If the corner of an 8x6 shed sinks a little its not big deal but a shed that big and in particular the roofing felt may be damaged by sagging if the base settles.

Id be very suprised if the mftrs recommended a plastic base on bare earth for a shed as big as you are considering.

Hi thanks for the further info. I am leaning towards concrete now considering the potential problems with just a sub base. I'd have to lay a sub base for the concrete anyway so effectively there isn't much more time involved in concreting I suppose. And yes it's a large shed/workshop so it makes sense to go to the extra effort especially if as you say a shed this side may settle and self-damage. Thanks for your help!