Extending a Concrete Base

[Johnny Dangerously]

Hello,

I have a bit of a dilemma, and I'm not great at things like this so I wonder if you guys can offer some advice.

I have a small shed at the bottom of the garden that is on top of an approx 3/4 inch concrete base. This doesn't reach the back garden fence and there is an approx 20 inch gap at the moment. I want to build a small garage in its place that backs on to the back fence, and also extended it the opposite way a little so I can store my bike in there.

My question is...is it possible to extend this slab, i.e dig and concrete the current gap, and also the extension portion, and then apply a 'screed' over the top to give it the appearance of being one slab?

Or

do I have to dig up the current slab and create a whole new one?

Not sure if that makes sense but any advice would be appreciated.

Thanks in advance

JD

 

[countygardens]

If your building on it, I would say that 3/4 of in inch is very thin How about footings for your walls

 

[Johnny Dangerously]

Sorry, should have said, its still going to be a wooden building, not brick. Just a bit bigger to accomodate a motorbike. Just a bigger shed really.

 

[countygardens]

In that case, in my opinion, you could probably get away with it. I would probably go a bit deeper with the new bit tho'

Anyone else have a better idea?

 

[Johnny Dangerously]

great....but do you think it is possible to apply a layer over the top to unit it all? Not sure about concrete binding to concrete.

 

[countygardens]

great....but do you think it is possible to apply a layer over the top to unit it all? Not sure about concrete binding to concrete.

It would end up being a very thin layer and probably wouldnt do much good. If you intend to extend then I, personally, wouldnt bother. (Maybe I'm just lazy)

 

[Johnny Dangerously]

thanks for the advice.....I'm still kinda tempted to hire a breaker and dig the old slab up and create a complete new one to make sure its as good as can be, but I may change my mind when I actually get round to diging all that up!

 

[chappers]

did you mean 3/4 of an inch as in less than an inch or did you mean 3-4 inches as in less than 5 but more than 2.
If the former than I would just dig the whole lot up smash it up as hardcore and lay a decent 4" slab.If you meant the latter then I would just shutter off the rest of the area and fill it with concrete.
With regards to covering it you would need at leastb 2 " to cover it succesfully, though you could have a go with self levelling compound.

 

[countygardens]

thanks for the advice.....I'm still kinda tempted to hire a breaker and dig the old slab up and create a complete new one to make sure its as good as can be, but I may change my mind when I actually get round to diging all that up!

That would be the ideal!

 

[Thermo]

if your not to worried about the cost (which isnt really that much) then id go for redoing it all

 

[Johnny Dangerously]

sorry, yes I meant it's appox 3 or 4 inches thick. I think for neatness sake, I'll break it up and get rid of it. At least that way most of the hole will already be there and I can probably use some of the rubble as harcorde for the new slab (assuming there isn't a lot of it under the slab already). Then I can make a nice new slab from scratch and please my perfectionist side.

 

[countygardens]

Deffo best thing to do!!