Shed base: concrete raft, concrete beams, wooden structure on posts, or ... ?

[<no_spam]

SWMBO has bought a good quality 8x6 shed so now I have the task of making the base and erecting the shed. The most obvious ways to do it is either a 3-4" slab or to make-up a wooden frame and support it on 6 or 8 posts. One way needs a lot of concrete and the other needs a lot of messing about and quite a lot of timber. I'm wondering about casting two 6" wide concrete beams about 4ft apart and 8ft long, then fixing treated 4x2s across them and sitting the shed on top. Has anyone tried this?

Are there any other alternatives apart from just sitting it on slabs?

[JimK]

Didn't this come up very recently?

Concrete fence posts? With dpms between the shed base and each of them....

Jim K

[Tim Watts]

It was a method I was considering and I rather like it - keeps the wood off the ground (use DPC on top of the concrete).

Don't forget you could cantilever (overhang) the bearers too - concrete strips say 1ft in each side so you only have a 3-ish' span and a 1' overhang.

Advantage - less spring. Disadvantage - if the bearers rot, the shed will not just neatly sink down until it sits on the concrete.

[David Lang]

I've done that several times - works a treat.

[Bob Eager]

Our shed supplier recommended that or a narrow raft, so that the water dripping off the bottom of the shed dripped off the edge rather than forming a pool round the bearers.

[Peter Andrews]

I simply put 12" x 12" paving slabs on the ground with a brick on top, then used four 8' 3" x 3" treated fence posts sitting on a bit of DPC/roofing felt. 30 years later no rot!

Peter

[CB]

Saw these in one of the sheds the other day and although sold as "decking supports" the thought of using them for shed supports went through my head.

[<no_spam]

I've searched but not found them - can you remember which shed?

[<no_spam]

That's a good idea - thanks.

I've found some very cheap adjustable pedestals (see link below) that could sit on paving pads to support the joists/bearers in a few spots down the span.

[<no_spam]

Certainly that would be less work, but I think casting concrete in situ is going to be cheaper and would give a better, more stable, result.

[<no_spam]

Thanks for all the responses - they've resulted in discovering adjustable plastic pedestals and a new line of thought.

I'm now wondering whether I even need a wooden support structure. With the shed joists sitting on the 2 concrete beams (cantilevered) and several of those adjustable pedestals (*) supporting the shed joists directly off paving pads the whole thing is off the ground and well supported. The only tedious work is digging, shuttering and mixing the concrete for the beams, but that's only about 0.05m3. It would need hatches or removable boards in the floor but I think that's do-able. What does the team think?

*Cheap adjustable cradles:

[CB]

Looks like you found another solution but in case anyone else is interested it was B&Q

(No I cant find them on the "new improved" web site) but they were in the store

[Syd Rumpo]

A good find, £1.51 each in small quantities is amazingly cheap.

I like the use of 'self-levelling' to mean you level them yourself :-)

Cheers

[Tim Watts]

I would upgrade the the Wallbarn ones

has the full range,

I've got some under my shed and they look very very well built - proper square edged thread and I wonder about the ecopads - the ring on them looks a bit thin and if it splits, there goes the support.

[rick]

See they are Self Levelling .......... must be real clever, I just looked at it and thought it would be screw adjust .... but self levelling wow.

[tabbypurr]

Small print, probably: * if installed on a level base. The self adjusting feature describes the action as the adjustable ring breaks and all set themselves to the same identical level.