This is a follow up for this question where I was asking for help on cutting in half and relocating a shed. The job is done and the result looks like this
I have take the shed out of there in order to build a proper base for it. (due to weather conditions I had to cut short my work last year). Now I would like to build a base using concrete slabs. As you can see in the picture my neighbor already has his shed in the same position.
Below is a schematic representation of the result with some relevant dimensions included
Question: what is the correct way to manage the rain water between these two sheds in such a way that nobody gets hurt. I have a gutter attached to the long side of my shed but my neighbor does not have one. I am plannig to ask him to attach one to his shed
The other issue here is this: I already dug a 5" base for my shed and I am going to add there gravel, slabs and a bed for slabs. Do I need to slope the subgrade (the soil) in order to make sure that the water moves away from the wall of my house?
Edit: I am contemplating a solution like this:
I will use concrete edging (long blocks 1.75"x2X35").The concrete edging will go below the subgrade level. The subgrade will be level. I need to focus on preventing lateral water infiltration. Above is the shed and I have a gutter so no need to worry about what comes from above. I need to worry above what comes for my neighbor if he refuses to add a gutter to his shed.
Below the bottom of my 6" deep cement blocks everything is a fair game, the water can go equally toward my house or his house. I was afraid that by digging the base for my shed I am going to create an area where the water would collect if in excess because it will be gravel and sand.
Best Answer
Sloping the soil would never be a bad idea, but more important is supporting the perimeter with a proper foundation. Why do you need a slab at all? Assuming you have a reason for using a slab I would normally recommend a "floating slab" setup, but that is probably not feasible because you are placing a pre-built structure there. A floating slab would require the perimeter foundation to extend above grade in order for your floor to be level with grade. Not possible because your walls and floor are already built. An alternative would be one like shown below (dimensions shown could be reduced appropriate to your structure size). It is critical that the soil and gravel below be compacted.