Shed base

[tommyleestaples]

Hi all,

 

I need to purchase a large shed at least 10ft by 14ft. I already have a concrete base at the end of my garden where the shed would go. The concrete is fairly level from what I have been able to check. 

 

Could I put the shed straight on this base or does it have to be raised up to prevent rot? 

 

If it has to be raised up what would you recommend is the most effective way of doing this?

[Conor]

Raise up on small paving slabs. You need airflow under the floor.

[tommyleestaples]

29 minutes ago, Conor said:

Raise up on small paving slabs. You need airflow under the floor.

Thanks for your reply Conor. 

 

It looks like the shed is already raised off the floor would this be enough air flow?

 

 

[joe90]

My potting shed is supported by these, no rot plastic and lots of airflow, just google “plastic shed base” there is lots out there.

 

https://www.diy.com/departments/plastic-interlocking-shed-base-w-49cm-x-l-49cm-pack-of-4/5060192725094_BQ.prd?storeId=1174&&&&&gad_source=1&gclid=CjwKCAjwr7ayBhAPEiwA6EIGxPm61JqUItpmSZMqY-arilYsUOMKxwbAfg5uU8J5kG0mzxgyGuiRqBoCFocQAvD_BwE&gclsrc=aw.ds

[Alan Ambrose]

The idea is that you would rather not have the base (or any other bit) sitting in water for any length of time as it'll rot.

 

Another option to raise it up, if your slab is level, is gravel grid.

 

If you are careful with gutters, down pipe exits, drip edge, think about water splash from rain hitting the floor etc, it'll last a long time.

 

I might be inclined to use epdm for the roof as it'll last longer. I also might beef up the floor a bit as it's that that'll fail first.

[Andehh]

2 hours ago, tommyleestaples said:

Thanks for your reply Conor. 

 

It looks like the shed is already raised off the floor would this be enough air flow?

 

 

 

That will work fine, just try to avoid any pooling of water underneath it. Guttering and downpipes that eject water  away will mean the shed probably out lasts you.

 

We recently moved a shed that had been sat on a concrete slab for well over a decade, other then some green growth on the shaded side, it dismantled fine and has been setup again somewhere else on paving slabs. Repaint it all and it'd look new.

 

If you really want to go to the extreme, paint the bottom of all the timbers in bitumen paint before you put them on the concrete.

[tommyleestaples]

As you can see in the picture the shed floor is raised off the floor by some supports running underneath. I will also look into the plastic grids but just a question I have a decking area of 50sqm that I need to remove and get rid off the boards are in good order. 

 

Could I run these decking boards underneath the new shed to take weight and just raise the whole shed up off the floor more?

[joe90]

10 hours ago, tommyleestaples said:

Could I run these decking boards underneath the new shed

Yes but again it’s timber and will rot eventually.

[Conor]

10 hours ago, tommyleestaples said:

As you can see in the picture the shed floor is raised off the floor by some supports running underneath. I will also look into the plastic grids but just a question I have a decking area of 50sqm that I need to remove and get rid off the boards are in good order. 

 

Could I run these decking boards underneath the new shed to take weight and just raise the whole shed up off the floor more?

 

Those supports are for the floor structure and aren't meant to be on the ground. You want just a few points of contact. All you need is half a dozen 400x400mm pavers from B&Q, or plastic crates as others have said.

[tommyleestaples]

Thank you all for the advice on plastic grids. I plan to put them on top of the concrete base and then put the shed to raise it up off the floor. 
 

Would I need to fill them with pea shingle as shown on instructions or not as they are going on a solid concrete base rather than soil 

[Alan Ambrose]

Yes, they get their strength from the fill. Use sharp stone rather than rounded shingle for max strength.

[joe90]

26 minutes ago, Alan Ambrose said:

Yes, they get their strength from the fill. Use sharp stone rather than rounded shingle for max strength.

I disagree, my shed base plastic trays were made to have no stone Infill. It’s only a shed, the drive gravel trays are different as cars are a lot heavier.

this is the ones that came with my shed.   https://shedbasekits.com/product-category/probase/

Edited May 24 by joe90

[Alan Ambrose]

Depends what you have in your shed I guess.  I have a bunch of heavy machine tools in mine.