How to add drainage for around the shed?

[EvansT]

I have had a 6m x 6m shed put in with the slab quite high off the ground but I have been informed due to where it is located that I should have drainage in around the slab to absorb any water that may settle next to the slab. I was wondering if drainage gravel may be enough (and removing the dead grass / weeds) or whether something extra is needed like a French drain or a slotted pipe etc? Someone even suggested a small retaining wall around the ground and then fill between the retaining wall and slab with drainage gravel. 

Any help is greatly appreciated. 

[JacobZ]

Hi @EvansT,

Thank you for your question regarding drainage around a new shed slab.

The option you choose is really dependent on the lay of the land. If this corner is a high point in your yard and the ground water flows away from this shed naturally, I would suggest that a layer of drainage gravel approximately 100mm thick should be adequate to allow the water to run off without pooling.

If it is a low point where you receive a lot of water, I would suggest installing socked agi pipe to collect any ground water and have it connected to a stormwater pipe by a licenced plumber. 

If it was my shed, because I always like to future proof as best as possible, I'd take the opportunity while the area is still relatively accessible to install a French drain using Grunt 2 x 20m Non Woven Geotextile Membrane, socked agi pipe and drainage gravel.

You might like to check out How to install garden drainage for some guidance.

Allow me to tag some of our helpful members who love a drainage project for their thoughts @Dave-1, @Nailbag @TedBear.

If you have any further questions, please feel free to ask.

Jacob

[EvansT]

Hi @JacobZ, 

Thanks so much for the advice. I think I will put in a single or possible two-level composite retaining wall to hold the dirt back against the fence to be sure and then compact the dirt down and put gravel down with a fall from one side of the shed to around and down the other side, using the Megaflo 170 x 40mm 20m Green Socked Slotted Agi Pipe with fittings. This way I can end cap a T fitting to go around the 90 degree corner and connect to a 90mm pipe at the end, and put more drainage gravel over the top of the socked agi pipe. 

The area doesn't get a lot of water - just with the sudden drop from the land, I just don't want water to sit and make under the slab too wet and cause issues down the track. 

This is a great solution, thanks so much for your help. Let me know if anything I have said above won't suit. 

Cheers.

[Dave-1]

Good Evening @EvansT 

Think you have found a solution My response is pretty much the same as yours and @JacobZ  Would love to hear how it turns out next time it rains heavily. Fixing or mitigating water issues around the yard is always interesting.

Dave

[EvansT]

Thanks @Dave-1. I will let you know how it goes next time it does. 

I will put up some photos once I have completed it all too. 

Cheers.

[JacobZ]

Hi @EvansT,

Sounds like a brilliant plan. Like I said earlier, it is always good to future proof when you can and your plan is certainly doing that.

Keep us updated as your project progresses and if you would like further assistance or opinions, please let us know.

Jacob