# Concrete floor in Existing Shed



## Scottydog (May 1, 2016)

I have this metal shed on my property and I would like to put a concrete floor inside. As it sits, it has maybe 9 anchors "screwed" into the ground then bolted to the bottom rail. Does it make sense to just dig out the inside a few inches, then pour up to the top of that bottom rail? OR, do I need to dig under the bottom frame and get concrete under there as well? It has even been suggested that I remove anchors, and lift the shed, pour slab that extends outside the frame, then set it back down. Not sure how or if I can manage this task.

Thoughts, suggestions please


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## melli (May 7, 2016)

Ideally, the last option you mentioned is best. 
Having concrete under sill plate (bottom rail) allows you to put in anchors.
Looks like a light shed, relatively speaking. Undo existing anchors, use a crowbar to raise...jam some 2x underneath...work your way around. Once up a few inches, your good to go...I'd just throw up 2x6 all around shed as form for pad and rebar. 
The nice thing is you have cover for pour.


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## Scottydog (May 1, 2016)

melli said:


> Ideally, the last option you mentioned is best.
> Having concrete under sill plate (bottom rail) allows you to put in anchors.
> Looks like a light shed, relatively speaking. Undo existing anchors, use a crowbar to raise...jam some 2x underneath...work your way around. Once up a few inches, your good to go...I'd just throw up 2x6 all around shed as form for pad and rebar.
> The nice thing is you have cover for pour.


I agree but was hoping someone would have an easier option. Looks like my hi-lift will get a workout.


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## Fishindude (May 19, 2015)

Metal sitting right on the ground is no good, it will eventually rust out.
I would either move it out of the way and build a proper foundation or jack it up and temporarily so that a foundation could be installed. Option #2 will make the excavation much tougher. Ideally I'd want the building sitting up on a concrete "curb" 6" or so higher than the new slab.

If you are located anywhere that experiences ground freezing, you will want foundation to extend below the frost line.


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## melli (May 7, 2016)

Scottydog said:


> I agree but was hoping someone would have an easier option. Looks like my hi-lift will get a workout.


Haha...there is always an easier option, but easy and good option, I don't know. Maybe a good time to think if the shed location is ideal...given it is a metal shell, probably not too difficult to skid somewhere else. 
A quick and dirty way, is to put PT sleepers under walls, and use them as forms for concrete inside (being mindful to have a really good sill gasket or PT wood will dissolve metal. And as noted, have really good drainage so pad doesn't heave if in a cold zone.


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## Bearfootfarm (Jul 13, 2006)

Jack it up and set it on brick or block instead of lumber.
Only use lumber around the perimeter of the form and pour the concrete around the supporting material so it extends beyond the building.

You don't really need footings for a structure that light.


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## Hitch (Oct 19, 2016)

Instead of pouring concrete why not use pavers. I️ know it’s not the same, but could be a hell of a lot easier then trying to pour cement under an existing structure.


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## itsb (Jan 13, 2013)

raise it up a few inches, take the center post out, and back a trailer in and put cross boards to floor of trailer and to wall post and let it down and pull it out of the way and pour a slab, back it back in place and bolt it down and replace center post.


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## Fishindude (May 19, 2015)

After giving this some more thought, here is how I would do it:
a. Raise the whole thing up off the ground 12" to 16" by whatever means you can come up with and hold it up with wood cribbing.
b. About every 6' to 8' around the perimeter shovel out and pour a little pad of concrete about 16" diameter x 6" thick. 
c. Drill a hole thru bottom tube frame of building over the concrete pad, and insert a long 1/2" - 3/4" threaded rod thru hole into wet concrete pad allowing it to set up. 
d. Have a nut and washer on bottom of threaded rod under the bottom tube frame of building. This will allow you to level the building and hold in place at proper elevation approx 6" above current grade.
e. Adjust nuts using a transit or builders level to get bottom of building perfectly level.
f. Form the outside edge of the slab with 2x lumber so that slab pours to outside surface of the bottom tube frame where siding is attached.
g. Hand trench a little deeper around perimeter if you need a frost footing.
h. Pour the slab and perimeter footing monolithic.
i. Now use those threaded rods as anchor bolts to hold building down by having a nut and washer on top of tube, trim off any excess threaded rod.


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## Bearfootfarm (Jul 13, 2006)

That's an awful lot of work for a building that really doesn't need any footings.

Setting a couple of large square concrete pavers or cinder blocks would accomplish the same thing, and the anchor bolts could go in the poured concrete.

The OP wants an *easy* solution.


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## bobp (Mar 4, 2014)

There's a guy down the road that built one similar, a few years later he screwed 4" asphalt expansion joint to the bottom of the metal, threw enough gravel in to level the low spots and ordered concrete... looks fine...May eventually rot the metal...But he'll be dead by then..Easy peasy....Not a great idea...i believe blocking it up and pouring under it would be best... But it is easy


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