[GardenShed]

Later in the year I am planning to purchase a shed.  The area it will go is currently a bit overgrown, with a few blackcurrant bushes and weeds.  I am planning on cutting it all back to ground level, digging over any significantly uneven bits to try get it fairly level, then covering with black plastic.  I was then going to put sand (builders?) on top, and then some paving slabs.  Ill then get the slabs level by adjusting the sand underneath.  Shed will then go on top of the slabs.

Does this sound OK?  Also, am I right to put the black plastic between the ground and sand, or should the order be ground, sand, black plastic, then slabs?

Lastly, I think I'll buy a 6x4 or 7x5 from a DIY store, but out of interest is it worth considering building the shed from scratch?  How hard would this be?  And assuming I purchased the materials as opposed to collecting and recycling, would this be cheaper than a standard shed 6x4 which costs about 200 pounds?

Any advice appreciated. Thanks.

[dub dub]

I did mine last year, I did a concrete base as I have access to a cement mixer, dig out plus lay took a day.

If I was slabbing it I would dig out weed roots, use weedkiller, compact 100mm Type 1 stone,  then do a thin layer of sand under the black plastic to prevent any stones etc piercing it. I would use grit to lay the slabs on rather than sand. If you level two lengths of wood each side of the bed you can screed the grit to level it. Then just place the slabs.

[GardenShed]

Thanks for the reply - why grit as opposed to sand? And what is 100mm Type 1 stone?

[cadalot]

Thanks for the reply - why grit as opposed to sand? And what is 100mm Type 1 stone?

Graded hardcore for under roads / slabs see http://reviews.wickes.co.uk/9987-en_gb/224665/reviews.htm

[Lardman]

It all depends on how properly you want to do it, is it your plot shed or one at home?

All the hard landscaping is nice especially if you're wanting things to last decades, but there's no real need, after all how long is the guarantee on the shed. You can happily level the ground, tread it down drop a couple of slabs on top and site your shed. As long as there's good airflow under it, there's nothing to worry about, no need for sand, chippings or black plastic. The floor bearers will rot eventually - but it's going to take a good few years.

The last one I built from scratch (buying new materials) cost 50% more than the equivalent size from the local shed company.

[LilacSandy]

I'm with Lardman,  my shed has been up for three years, just levelled the ground, put down a few slabs and it is standing nicely and no problem with anything growing underneath as the shed itself stops light getting to the weeds.

[cadalot]

I levelled the ground shoved some sand over then some slabs as the shed is 6x4 I used 8 slabs with gaps between for air flow under the floor

[GardenShed]

That's really helpful and reassuring.  The shed will be on the allotment.

I think I'll clear the area, lay plastic until I'm ready to put the shed up, then put down sand and slabs.  I'm hoping the sand will be useful in getting the slabs level, rather than having to spend ages digging over and levelling the land.

It sounds like it will be cheaper to buy a 6 x 4 shed from a shop.

If I cannot get hold of any second hand slabs, which type / size should I buy?

Lastly, how long roughly does it take for two people to put up a standard shed once the slabs are down?

Thanks.

[cudders]

I put up a 6x4 myself in about an hour and half. Easy job really.

Cudders

[cadalot]

If I cannot get hold of any second hand slabs, which type / size should I buy?

Normally they are 400mm or 450mm square so 1.8x1.2 6ft x 4ft you need 3 x 4 =12 slabs. If you get the smaller ones then leave equal gaps between the 4 on the 1.8m side and air can get under the floor timbers in that direction, see the photo below.

And it only took an hour and half to erect and felt the roof once the slabs were done.

[GardenShed]

Thank you that very helpful.  In terms of the example of using 12 slabs (45 x 40) for a 6 x 4 shed, roughly how wide will the gaps be?  Is it basically just a case of leaving a few centimetres between slabs or does it need to be much wider?

[cadalot]

Basic Maths stuff this really

if 400 x 400 then 400mm x No = 1600mm the shed is 1800mm so 1800-1600=200 then 200 / 3 gaps =66.67mm for a perfect fit

or round up so to say 75mm 3" gaps then your a little longer than the shed 1600+75+75+75 = 1825mm

Re the width 3 slabs x 400mm = 1200mm which is 4 ft anyway

If you use 450 x 450 then the width is 3 x 450mm = 1350mm which gives you 75mm either side over and
length wise 450 x 4 slabs = 1800 which is spot on.

[GardenShed]

OK I see.  I guess I was also wondering what the ideal size of gap should be between slabs? Does there need to be any gap at all?

In your example are you saying that you would have gaps between the slabs length wise, but width wise they would be butted up against each other with no gaps?

[cadalot]

Yep - look at the photo I uploaded