Went too far digging out the old shed base!

[jonclancy]

Hi Everyone,

Seeking a little advice here, please. I demolished our old, rotten shed and it left a disintegrated wooden base. While having some digger work done, I asked the operator to dig out the base. He did a great job, but I think I asked him to go deeper than necessary. We’re on clay and I’d like a permeable base for a new shed. The area dug out included an old greenhouse base too. Lots of room for a decent sized storage shed. I don’t want to cast a concrete base, as the shed may move if we do our side extension. Easy to dig a foundation through some compacted scalpings.

I was thinking a layer of scalpings, wackered, and then topped with some 50mm ecogrid-a-like from Wickes. I have some visqueen, and was wondering how I would ensure that the pit wouldn’t become a paddling pool in heavy rain. We are also on a slope, as seen in the pics. The area is 2.4 x 4.4m.

Thanks for your thoughts/suggestions!

Here are some pics.

 

[addjunkie]

A french drain off to the low side, routing excess water away….

 

[Bobtail4x4]

use sharp gravel instead of scalpings, the water will pass through it,

 

[gaz1]

dig more out on the highest point

shutter and fill with a concrete base at the highest point fill with pebbles creating a french drain at the highest point that will go around the front of the pic and be released into rest of the garden

 

[tom2207]

if its only temporary , stones , quarrydust and flags ,,, if its staying , concrete and a soak away .

 

[arther dailey]

old council 2x2 slabs are usefull , as can be lifted and moved when you need.

 

[RonMig]

Breeze blocks are fairly cheap, easy to handle and would give an easy 4-inch lift for shed bearers.
Also easy to move them & re-use when you need to...

 

[dobbslc]

Now you've already dug it out I'd say it needs filling with concrete or MOT type 2 wackered down as you really don't want a swimming pool under the shed if water can't drain off.
It looks like you have some chalk in that soil so all may not be lost as far as drainage goes.

 

[gaz1]

Breeze blocks are fairly cheap, easy to handle and would give an easy 4-inch lift for shed bearers.
Also easy to move them & re-use when you need to...

do not use breeze blocks near water

 

[Pete.]

If it's just a shed I'd put in a bed of type 1 or crushed concrete, wack it down, dpm, thin slab then put your shed on it.

The chalk is a good sign nice stable ground.

 

[pedrobedro]

do not use breeze blocks near water

Breeze blocks are not for outside use, you want concrete foundation blocks for use in contact with the ground.

 

[Wildefalcon]

Galv ground screws?

 

[8ob]

Shutter it and concrete the base, bring in ground levels when you strike off the shutters.

 

[Pigeon_Droppings2]

As above...Type2 followed by whatever top you want.

Slabs or ecogrid is fine...if you are worried about damp then sit the shed on adjustable patio props...they're plastic so won't rot and will make the leveling very easy.

I personally dislike seeing cement in a garden but each to their own!

We live on a slope with a north facing garden...i built a garden path which is basically a hidden drain...worked very well.

 

[jonclancy]

Hi Everyone,

Thanks very much for your excellent and varied suggestions. I missed a most important detail on my OP. We are on clay! The stone is just some old ballast and chippingsthat have been disposed of in the hole. My kids are enjoying excavating it, but they keep on digging up glass etc, so I need to get something down reasonable quickly.

We’re going to have a look a it tomorrow and come up with a sensible plan. Thanks again for all the fabulous input!

 

[bricol]

I do wonder . .

Customer spec - I don't want concrete, I might want to move it.

Answer: concrete

 

[addjunkie]

I do wonder . .

Customer spec - I don't want concrete, I might want to move it.

Answer: concrete

Concrete is easy enough to remove. Digger, pecker and off you go!