Can i build on pre existing slab?

[ghostknife]

Here is my question, if it was a solid piece of concrete i know i could but what happens if the slab is multiple pieces. It looks like it was poured in 12x10ft sections. I was thinking of using the concrete since it was already there. The building will be just storage for the boat and atvs. Could i possibly pour a 1-2" cap of concrete over top of the pieces to make it one? If not no biggy, the slab was there from the previous owner so no money out if it wont work. I have a picture of the slab and the red lines show the cracks (lines) in the concrete. The pad is a 36x26 without that small cutout



EDIT: dont mind the wind blew my boat off the pad lol

 

[Von Psycho]

I dug holes every 8' and put pressure treated poles 4' deep around a 16'x24' slab I had
and didn't touch the pad at all.
Everything worked out good, just a suggestion.

 

[PugetDude]

Here is my question, if it was a solid piece of concrete i know i could but what happens if the slab is multiple pieces. It looks like it was poured in 12x10ft sections. I was thinking of using the concrete since it was already there. The building will be just storage for the boat and atvs. Could i possibly pour a 1-2" cap of concrete over top of the pieces to make it one? If not no biggy, the slab was there from the previous owner so no money out if it wont work. I have a picture of the slab and the red lines show the cracks (lines) in the concrete. The pad is a 36x26 without that small cutout



EDIT: dont mind the wind blew my boat off the pad lol

Looks like you've got a great slab to build a pole barn around.

 

[ADSR]

I'd stick frame it. Slap some gasket and plates down and go for it.

 

[ghostknife]

Good to hear you guys think it would be good to go! Thanks for the quick replies! That shed already has electric ran to it, so that makes things easier. Just need to move the shed off the pad.

 

[rburke65]

I would think that you'd be ok to build. Pad look ok?

 

[Cyberbear]

I don't think a thin concrete cap will do much good in the long run. You didn't mention if there were any kind of footings around the perimeter or not, but having something there would be best, even if it was only a false footing.
I agree with the stick built idea but a double mud sill or a 4 x 4 would help spread the wall load since you are only using it for light storage. If you decide to pour some footings under the slab edges, be sure to put some steel in there to keep everything in one place.

 

[ghostknife]

The concrete is in pretty good shape, though not too sure on the footings or even thickness of the pad. This was kinda a spur of the moment thing as im sitting at work. I will check tomorrow. This is going to be a basic build since the wife wants to move eventually, probably in 10-15 years. The inside boat storage for the winter by its self is $1000 a year. So as far as i see it, it would be worth it in the long run to keep it at my place.

 

[iminocca]

If I were going to stick frame a building I wouldn't want all that weight on the edge of an unreinforced slab. If there's a footing, then no worries! If not, I would be inclined to rent a saw and make the slab the shape I wanted (probably a rectangle) and pour a footing around the perimeter of the slab with dowels into the slab to hold them together. That way you could keep your framing far enough above grade and build on top of the new footing and insure the stability of the building. If you just want to build on the slab I would look at a lighter weight steel building....just my $.02...

 

[stikman56]

If I were going to stick frame a building I wouldn't want all that weight on the edge of an unreinforced slab. If there's a footing, then no worries! If not, I would be inclined to rent a saw and make the slab the shape I wanted (probably a rectangle) and pour a footing around the perimeter of the slab with dowels into the slab to hold them together. That way you could keep your framing far enough above grade and build on top of the new footing and insure the stability of the building. If you just want to build on the slab I would look at a lighter weight steel building....just my $.02...

This is what I was thinking too.

 

[bazzateer]

With the steel building you could take it with you when you move.............

 

[ryan77]

yes, the ALLSTEEL buildings (or similar brands out there)are built very sturdy and would be quick and easy to bolt down.

 

[volleyball]

Without a thick, solid, level pad, it seems best to pin and pour over it. And do a perimeter footing. You then have a base to build what you want.

 

[ghostknife]

Thanks for the imput guys! I like the idea of taking the building with me lol. Just pack everything, including the barn. Ill have to look who does them up in Michigan.

 

[Pitt Grease Monkey]

I would be hesitant to build directly on the pad without knowing more about it's construction. Assuming it is a floating slab I would be more worried about the frost heave you will get in the colder months. This could destroy a well built building in no time. Stick built or steel, if you jack one corner up 4" you're in for a lot of repair in the future. At a minimum, I would verify the slab has a frost wall around the perimeter before doing anything. Easy enough, just dig down at the edges.

If it were me I would leave the slab alone and dig/pour individual column footers or a continuous footer the whole way around making sure to be below your region's frost depth. Similar to what imonocca described. I'd then use that for my walls.

 

[ghostknife]

The plan will probably be surround the existing pad (26x36) with a 30x40 building with a whole new frost wall. The cement hasnt budged in the 4 years i have owned it with the heavy shed sitting on one corner of it. It is probably due to the fact i have no graound heave lol. I am on solid clay. When i put in my fence, i rented a 2 person auger that had a 10" bit and it barely would turn it through the clay. Once i got the holes dug with the auger i felt down in them and the sides of the holes were turned to pottery from the heat. Oops. If there ever is a tornado that comes through, I am sure the fence will be the only thing standing.

 

[volleyball]

Clay expands and contracts with moisture. I had door that would stick at certain times of the year until I rerouted the water.

 

[ryan77]

if I was worried about the frost heave, I'd erect the steel bldg., then drill and anchor a eyebolt and chain it in the corners with slack in the chain, that way the wind won't blow it away, and if the slab heaves the building isn't twisting with it, those ALLSTEEL steel bldgs. are tough, isn't going to hurt them at all. keep it cheap and simple!

 

[SteveCh]

If it's all flat [no sections sinking], pour another little pad to fill out that corner, if you want, then just do it. I'd leave it alone. I mean, you're gonna put up something to store the boat, just keep it simple. If you end up framing the walls, use a hammer drill, set some anchors in the perimeter, bolt down the walls. Done.

 

[zcar751]

If you put a 30x40 pole building over it I would just fill in the parimeter with concrete. If you really wanted to cap over the existing concrete you would want at least 3 inches to prevent large chunck from breaking out. If you go stick or metal I would do footers below frost level and fill in the parimeter.

 

[mikegt4]

When my neighbor built his house he also built a pole barn of about 24' x 40'. A few years later a micro burst hit the front of the barn smashing in the overhead door and blowing out the walls. He had always complained that he couldn't get his small combine in the barn so he rebuilt it to a larger dimension (about 32' x 50') and taller for the combine. He sunk new posts outside of the existing slab and then poured concrete floor sections from the existing slab out to the new wall. Not long after that he got divorced (she was high maintenance and looked every bit of it). Years latter the new owners asked me why the floor had so many sections.