Foundations for a shed.....

Soldato
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Basically the Mother wants the shed moving so it is in another part of the garden. I'm not sure what it is currently sat on but fairly sure it isn't a full concrete foundation.

The idea we've had is to flag one corner of the garden so the shed can sit on that and she can also pop a greenhouse on it too.

Now my question is for something that isn't particularly heavy weight like an 8x6 shed (that isn't packed to the rafters with things, just stuff like the lawn mower, some deck chairs and few other bits and bobs) do we need to lay significant foundations in the corner?

I ideally didnt want to have the laborious task of digging out 10x10s worth of soil/clay etc to lay the foundation for it to be flagged over.

It's currently grass and soil and then under it it is quite clay'y but very unlevel. We've already dug out all the plants that were in the corner she wants it and all that is left is a bit of a tree trunk to dispose of.

Anyone any pointers or considerations? How big do we need the foundations? Do we need any significant foundations? Can it just be leveled off stamped down and paved over?

Any help/advice greatly appreciated!
 
I just have my shed, same size,packed to the rafters with heavy crates, on 50mm thick paving slabs, got off Freecycle, hasn't moved, subsided in 4 years.

Did laid down some bearers with dpm fixed along their length to stop any damp getting into shed base, then the shed laid on them.


There is no sub base like hardcore, just plain top soil which was compacted with garden roller.
 
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Mine sits on a 6" concrete slab on hardcore, however all I had to pay for was a few bags of dust the rest of the materials and formwork were lying around.
 
When we put up our shed in our current house there was some heavy paving slabs in the garden I wanted to remove anyway - just relayed them in the shape of the shed and stuck it ontop of that. 4 years on and its not moved so I'd guess thats fine!
 
People, in general, massively over-engineer shed bases. A quick scan around most DIY forums will show this!
 
It isn't just shed bases. Was doing some work for someone I knew whose son-in-law (an architect) had drawn up plans for a new build on his "garden" for him. We ended up putting almost three times as much steel in his foundations as the three-storey fire station rebuild 100 metres away was getting.
 
I was going to use paving slabs, laid on top of a bit of hardcore/sand. But I didn't want to destroy my car by picking up free ones and they were going to cost too much to buy, along with the hardcore and sand. Plus it would be a PITA if i ever wanted to get rid of it all.

Ended up digging some holes and then filling with concrete to create piers, with a timber frame sat on top. If I ever get rid of the shed I can just break the piers up a bit and then fill the area with soil. Plus they help to lift the shed above the ground to give some airflow under the shed and keep it away from water.
IMG_4908-3_zpsc4386084.jpg

As for the greenhouse, I just laid mine into a small ditch that I filled with a bit of gravel. Then laid a heavy duty ground sheet inside and poured more gravel for the floor. It helps water drain away when watering the plants and is again easy to get rid of in future.
 
Just done my 8x6 - I put mine on top of stone dust (just to level slabs), plastic membrane and then paving slabs. Definitely have the membrane layer!
 
My metal 8x6 is on limestone clippings abd then a treated wooden base and it's perfect.

I agree with Lopez, people massively over think she'd bases!
 
Haha cheers guys. Got some edging arriving tomorrow that I'll dig and place in the ground to form a bit of a platform for the paved area then will pave inside it once I've completely levelled.
 
When I laid my shed I followed a recommendation from a friend that actually worked great (although I was dubious at the time). I picked up 4 window lintels and sat the lintels on a couple of engineering bricks at each end that I bedded into the ground with sand. The benefit is it gave a nice air gap underneath to prevent damp, and when I moved house it was a doddle to bed in a few new bricks and place the lintels back down.
 
boxman - I am in the process of doing this.
So did you dust to create a level platform, membrane ontop of this and then the slabs?

Sorry, just saw your reply. Yes, I put the shed in the place of where my lawn was, also partly where a hedge had just been removed so was worried about the ground sinking slightly.

Basically I dug down 4" and put down the armoured power cable underneath (in one of those blue PVC water pipes for extra protection) and put in the hardc0re around it, putting stone dust on top just to level it off. I gave about 3" extra either side of the lawned area which meant I could mow right up to the shed without having to strim and avoid damaging the shed.

I then put down the plastic membrane and the patio slabs on top, giving space in between slabs for airflow but ensuring each joist was supported.

I also put guttering on one end (pent shed) and it's incredible how much water I've been able to collect, so much so that I'm going to get a second.

Still got some finishing off to do on my shed but on the 3" boarder around the shed I've put bark chippings for now.

Hope that helps.
 
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Cheers Boxman.
Sounds good. I have seen some people put the membrane on top of the slabs and then the shed on top of the membrane, so just curious.
Still trying to decide if the membrane is work it or not.
 
Trouble is you don't want the membrane to touch the wood as if for some reason water gets in underneath then it will just soak up through the joists, plus you don't get the same airflow underneath the shed.

Ours has only been up 4 months but has had a pretty good exposure to all sorts of weather and is absolutely fine.

I think the membrane I used cost me £8 from a hardware store so really was a no-brainer.
 
Well, funny you should ask. I just finished moving an 8x6 shed which was put in on pavers. The problem is that the trees near it have lifted and skewed the pavers. To be honest, the floor wasn’t up for much in the first place and has since rotted. So it’s move it, lift it replace the floor under it and re level it. Rather than go with pavers, I am going with cement pier blocks with adjustable posts so that future changes in ground level can be compensated.

I have another shed to shift for a client that is a similar size but that is level and hopefully will be easier to shift.
 
I just bought a load of interlocking plastic base plates and laid them onto flattened ground. They raise the shed a few cm off the ground and then I just installed tarp as both DPM and between the outer walls and inside OSB3 walls. Stable, dry and easy.
 
I ended up using these

I started with something like this but the problem I had was my ground wasn't perfectly level.
 
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