Little advice on best course of action for shed base...

[stormy121]

Long story short I'm banging my head against a wall trying to work out the best way around this, have a concrete slab and then slabs which was laid before we moved in, building my shed and have a rough outline but alas the floor is uneven by a good amount, I have attached photos to show the issue, I have thought about using slabs but I'm unsure how I would do it, would I lay sand on top of the concrete slab and level it that way or do I need to prepare it a different way? the side with the yellow level isn't a issue as I can just lift the slabs and get them level, Please help I am stuck XD

 

[Blackswanwood]

Hi Stormy121

I guess the existing concrete pad was for some sort of garden shed. How substantial and what is the basic design of your new shed?

 

[clogs]

pull the pavers.....sell or reuse.....
then put 4-6ins of new concrete on top...easy
just make sure the pad is secure to the old one......
a 2 dozen heavy screws would be OK......it give the new pad something to lock on to.....
I often get this job to do but on a bigger scale.....
I use 16-20mm rebar resin bonded into the old slab.....
some conc wire mesh would also be a good thing.......

I have to pour a 100m2 x 200mm floor on flat field stone connected to mother earth.....it has a 5º slope.....
it will get around 50 x 20mm rebar rods bonded to the stone to stop it moving in an eath quake, which we get here quite reg.....

 

[pip1954]

I would dig out where there is no concrete pull slabs up use them as hard to bring levels up smash slabs and well compacted then put minimum 4inches over all of it you get reinforcing mat to go over the join of the two different types concrete and hardcore .pip

 

[ChaiLatte]

Is the timber on which the spirit levels are resting the actual shed base?

Buy a piece of treated timber and make a wedge to fit under the brown piece. Planing a piece of wood is a lot easier than lifting and re-laying slabs.

In any direction where the water would collect (pool) at the high end of the sloping slabs, ensure the timber is not continuous so the water has a drainage path.

 

[MikeJhn]

Does the inside of the shed need to be level, as long as the edges are then just put the shed on top with a DPC under, perhaps even some tiles on sand and cement, it's only a shed not a habitable building.

 

[trvlr]

Solid bases for sheds are usually set with a modest fall to allow for drainige of rain etc. from beneath the actual shed; at least that's how it's been described to me by an excellent shed supplier locally. They offer (when required) either to install a solid concrete base (with a slight fall) or solid concrete post onto which a wooden frame is ancohored, onto which the shed is is assembled/built; or a little cheaper than concrete posts to use wekl treated timber posts rathert than solid concrete posts. Those timber posts being well treated to last at least 20yrs. and are embedded in concrete. When the shed is mounted on short concrete/timber post those post allow for ground, and also allow for all water to run/drain well clear of the shed base itself.

I've seen suggestions to use pea gravel/shingle in PVC cells to create a soldi (na level base for a shed. That doesn't need to have a slight fall as the water simply drains away through the gravel/shingle, and the shed base is usually sitting directly onto the gravel base; though some suggest having the shed slightly raised from the gravel/shingle - typically tanalised timbers supporting the main base - and maybe a DPC membrane between those timbers and the base.

You have a concrete base and it looks sound. Why destroy it? Simply use suitable shims under lengths of tanalised 2x4 or 2x3 - either in single lengths even braced/stabilised with shorter lengths between them. Or better still create a simple tanalised frame onto which mount your shed. Any actual mounting base should not extend beyond the outer cladding of the shed itself (i.e. the shed should overhang any support system initial base by an inch or two all round to allow for run off from the shed walls).

 

[StephenArfer]

Does the inside of the shed need to be level, as long as the edges are then just put the shed on top with a DPC under, perhaps even some tiles on sand and cement, it's only a shed not a habitable building.

I built my wooden 10 x 8 (internal) shed/workshop from scratch some 18 years ago. The slab was sloping slightly for drainage and my built floor also sloped slightly (about 5mm across width). I assembled and braced the sides vertical.

My machines and one bench are on casters, get moved around and in theory the working surfaces are at the same level and plane. Of course, with a sloping floor, that only works when two items are in the same relationship with each other. Rotate either by 90 or 180 degrees and the relationship is lost. It's irritating!

Also, I totally forget to insulate the floor so although the walls and ceiling are well insulated, my feet can get cold in the winter. I suppose the "easy" answer is to build a raised, insulated and level internal floor on top of the existing. Not easy for me at my age and physical condition, so I just think about it and wear boots.

 

[MikeJhn]

The OP did say shed, not Workshop.

 

[stormy121]

Thanks for all the replies! really helpful! I decided to leave the base as is and raise the front to bring it all level, 2x4s as a shed base to give it that extra height with some DPC under the beams, should be alright it is after all just a shed! I will store some stuff in it mind so want it to be more regulated in temps I guess, but my foundation is solid and the shed itself will be level and in theory should be watertight

Cheers guys! and here's to hoping it works

 

[stormy121]

Cheers guys! decided to leave the foundation as is and build the whole base out of 2x4 treated lumber, added a DPC and will level the shed itself but allow the underside of the floor to "breath"

Hopefully it all works out! Built lots of sheds before but I am no brickie so working with concrete etc was a new learning curve! have used bricks to bring it all to level and that's what the 2x4 sits on, works and I'm happy!

Thanks for all the suggestions and help

 

[MikeJhn]

A thank you would have been nice on my post.