small steel shed foundation, whats necessary and whats overkill?

fret_wimp2

Putting in a small steel shed (7 ft x 6 ft roughly), doing the foundation myself. Its not a big job but googling gives a number of opinions on whats necessary:

1. Dig away top soil, put down hardcore or sand/concrete mix and concrete slabs.
2. Dig away top soil, concrete.

Both cases can include a damp proof layer but again opinion differs if its needed.

Option 1 is preferable as its cheaper and means not carrying lots of bags of cement through the house, getting a mixer, sand etc, but if concrete really is worth it im ok with doing the extra bit of work.

banie01

I know steeltech recommend a "picture-frame" foundation for their sheds.
https://www.steeltechsheds.ie/concrete-bases/

I have an 8mtr x 5mtr steel shed that I use as a garden room and I laid a full insulated slab but thats for a totally different use.

jmBuildExt

That's a small shed - don't go too mad. Option 1 will be grand.

In my old house there was a wooden shed of similar size up on 4 blocks in the grass for at least 20 years and it never went anywhere.

_Brian

Dog the soil.
Lay hardcore.
Being hardcore up slightly proud of the surrounding ground the ensure I’m the shed base remains dry.

I don’t think there is need to concrete anything.

fret_wimp2

Thanks for the advice guys. Will be going the simplest route and avoiding concrete. hardcore, DPC & some slabs seems like it will do everything i need for a 7 or 8 foot shed.

daheff

I got a steel shed installed (off top of my head its 8*10). The company installing (PM for details) said that it doesnt need any specific base. They fitted it on top of bricks (looks like).

maybe you are overthinking this?

muffler

fret_wimp2 wrote: »

Putting in a small steel shed (7 ft x 6 ft roughly), doing the foundation myself. Its not a big job but googling gives a number of opinions on whats necessary:

1. Dig away top soil, put down hardcore or sand/concrete mix and concrete slabs.
2. Dig away top soil, concrete.

Both cases can include a damp proof layer but again opinion differs if its needed.

Option 1 is preferable as its cheaper and means not carrying lots of bags of cement through the house, getting a mixer, sand etc, but if concrete really is worth it im ok with doing the extra bit of work.

Really depends on what you want to achieve yourself. A concrete base/floor in your case will only be around one third of a cubic metre of concrete and thats giving you 100mm / 4" depth.

If you're going to the bother of removing topsoil and filling with with hardcore I'd put the icing on the cake and throw in a DPM on sand/804 and then a concrete base and another little tip would then be to ensure that the floor slab has a slight fall towards the door. Very handy for brushing or washing out depending on the use in years to come.

Think ahead of its use over a period of time and not just tomorrow

notaplumber

I purchased a steel shed (4x3m) from steeltech sheds 18 months ago. The builder on site installed the concrete base for me. It took 3 workers plus a mini digger 2 days in total.

Essentially he went with your option 1.

He opted for 'Option 2' in the attachment. (An internal 'Step', the base of the shed sits on the lower level, thereby eliminating any rain ingress).

Very happy with the finished result.