Concrete Garage floor help

[fushionjulz]

I'm looking for some advice and help...

I have a wooden garage over a concrete base that I want to move....

The building is 23ft long and 13ft wide approx...
It wants to move in a straight line approx 14ft lengthways.

The physical moving isn't an issue...However, the current concrete base is the same size as the building and the area to which it is going to move to is also concreted, but is approx 2" lower than the current floor...

Is it possible to lay a new concrete layer on top of what is already there?
Or will I need to break up the existing base and re-lay entirely?

We are going to move the structure by jacking it up enough to put scaffold bars under the width and roll on those...
Where can I hire 15Ft bars?

 

[r896neo]

scaffolding companies use the long bars with bolted joints as they are more versatile but you may have trouble hiring 15 ft bars as most hire shops hire out kwik stage stuff, If that's what its called?? You know star bars etc... the only thing in that stuff bigger than 9ft9 are the big brace/ supports.

 

[noseall]

Sounds like an interesting project.

I guess scaffold tubes may work but they are a little bit narrow and may not allow for much deformation. You can get just about any length you like up to 21'.

Quick-form scaffold is what you are thinking of r896neo.

Plus how are you going to push/pull the structure?

Will it be rigid enough to withstand the trauma?

 

[r896neo]

i new it was quick bloody something!

 

[Deluks]

Am planning something similar for my 12x8 shed. It's on a brick plinth so I will simply build another couple of courses of bricks matching the existing plan. Then scaff poles underneath as you say (between brick and timber plate) then attach a winch to a large cypress in my garden and pull it along. Will need to brace door and window frames to avoid distortion and get a couple of mates with 4x2's and sledgehammers to keep it in line during the pull.

The concrete base is my floor, so I will be cutting poles into foot long lengths and placing around the perimeter.

If you have a built in floor that needs to move with the entire structure, you could still roll it using shorter lengths of pole, jack up either side and slide 8ft lengths under each side, roughly meeting in the middle. It should still move.

Otherwise follow my plan above.


You could make up the 2" gap by using paving slabs in a line.

Alternatively you could cut channels in the lower concrete floor (inch deep plus mortar bed depth), and lay a course of engi bricks level with the higher base.

 

[TicklyT]

I would have thought short rollers, say, 3 feet long would suffice. Only the bits with something resting on top do anything. The bit in the middle would, IMO just get in the way.

 

[noseall]

I would have thought short rollers, say, 3 feet long would suffice. Only the bits with something resting on top do anything. The bit in the middle would, IMO just get in the way.

Don't count on it.

A 13' x 23' shed is not going to be all that rigid, in fact it will be like a wallowing beast and will need all the support it can get.

A scaffold tube is a little under 2" diameter, couple this with a slight rise in the ground and a sagging shed bottom and the whole show will grind to a halt.

I have mt doubts in any case unless the shed is stiffened to withstand the push/pull forces.

 

[fushionjulz]

Thanks for all the replies and advice...

I have two Joiner/Carpenter friends who are assisting me as they have done this type of move before...only on a slightly smaller scale.

The structure is pretty well built and looks fairly rigid. However, we intend to fit some temporary cross bracing to ensure it is a bit stiffer during the move.
My friend has recommended bars long enough to fit under the shed side to side to avoid any possible issues with flexing.
However, shorter ones may still be an option.

The base is pretty level (I've measured it) and the bottom of the shed has a reinforcing strip on which the sides are sitting and bolted to via metal angles...

The floor isn't built in...the structure sits ontop of the base...

The first task, though, will be to lay the concrete base...
Looks like I'll have to be making the concrete myself as the volume required isn't big enough for a readymix pour....

I really need to know, though, if I can pour directly onto the existing concrete base or if I need additional prep.

 

[Deluks]

See here: //www.diynot.com/forums/viewtopic.php?t=215631

Bottom line, 2" unlikely to cut it. Concrete doesn't stick particularly well to itself. 4" of old concrete plus 2" of fresh concrete will not give you 6" of concrete. It will only be as strong as the weakest element.

One trick you could try is to bolt down some A142 mesh to the existing, and then lay onto this. The mesh will hold the 2" concrete together somewhat, and bolting the mesh down somehow will give you the bond. Might get some surface cracking but adding poly fibres would reduce this.

Never tried it myself, just a theory but I'd trust it over just slapping down 2" and hoping for the best.

This idea doesn't take into account water ingress and potential corrosion of the reinforcement. Although using stainless bolts and mesh would probably solve this issue. At a cost!


Other options include: laying paving slabs over the lot, full bed mortar base and pointed up.

Screed or self levelling compound, can get pricey, wouldn't trust it to take the weight of a building.

 

[fushionjulz]

Just providing a "job done" update...

Firstly we laid a concrete base extension over the part of drive in front of the garage using a metal re-inforcing grid...the depth varied a bit, but was a minimum of 2" (5cm)..

After that had set properly we levered up the garage onto short bits of scaffold pole and pushed the whole structure into place...Took 3 of us a total of 2.5hrs start to finish!

The roof was then recovered with 3 layers of felt, properly stuck and finished...
The bottom plank of the shiplap cladding sides had to be removed as the planks were rotten and they originally overhung the concrete base...I'm in the process of replacing these now...