Concrete to Grass Conversion!

[astroADF]

Hi all,

It's ideally going to be a weekend project, though I'm deadset sure it'll take longer! I thought I might post it here out of interest, though also for my own reality check down the track :)

I have a roughly 3x3 metre area of concrete in the backyard of our semi-detached in Marrickville, Sydney. This weekend? I'm ripping that concrete out and replacing it with grass.

I've hired a jackhammer and a sledgehammer, and will be cracking on first thing this Saturday morning.

Ear plugs are ready. Eye protection is sorted. Here's a couple of before-shots, which by Monday I hope to be posting the after-shots! (there's been a lot of development since these, as they were early days when we first took ownership of the house, especially the delightful pink walls with tile window border):

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*Scanning for underground cables / piping, of which there is none I'm glad to say.

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*Not including the inside of the carport. The concrete in there is staying)

Anyone got hot tips they can pass on? It's the first time I've used a jackhammer for this purpose, so I'm just going to establish a corner-crack, and bang away.

Note: I don't know if it's reinforced, and hoping it's less than 100mm deep... by Saturday I'll know!

[rrobor]

Looks like a pro laid that so there will be rio. So get bolt cutters or an angle grinder and get rid of the shorts. Get descent gloves, buy a lawn mower, lawn grass, grass starter. Oh fit a watering system. And once youve stopped bleeding from being ripped by flying concrete, ask yourself wouldnt fake turf be better?

[astroADF]

Damn; as a lot of the house mods have been amateur jobs, I was hoping the concrete would be the same. The angle grinder is at the ready; then it might be a question of just how deep I need to go.

That's not me by the way - that's the geezer who came to scan for cables and piping, of which there's none thankfully. Except for the mystery object; I've another post on that. In electrical I think. It'll obviously be ripped out with the rest.

[Ronaldo451]

Have a dumpster ready to put the debris straight into - you'll be surprised at the volume of concrete that ends up being removed and how much it gets in the way. Can be a real trip hazard in a small work area like yours. I assume you have a wheelbarrow or two.

A sledge hammer and crow bar is also handy for a change of pace occassionally - lift a slab and give it a whack - to give the hands, arms and shoulders a break from the vibration. Good Luck

[murray44]

I have no idea what size jackhammer you hired but you'll be wishing you got the bigger one. :C

[astroADF]

I'm thinking exactly that already! I spoke to the bloke at Kennards hire and described the job, so he *hopefully* will be giving me the right tool.

I'm already considering my fallback plan; ie: getting on the blower and getting a professional mob out to do it :kickcan:

[rrobor]

You know, this poor bugger thinks its his Idea, Nah the wife planted that seed a while back. What its all about is keeping him at home. 'Youve got the grass to cut dear". Bang goes his Saturdays at the match and a pint in the pub afterwards. Its all a conspiricy by women, They've been at it since Adam was a lad. The make us build things, that way we are not out there hunting. And if we are very very good, we can buy a new tool.

[Project1080]

Astro.
Did a similar job a couple of years ago. Replaced old verandah with new one and deck under. Bought myself an Ozito jackhammer from Bunnings for $99 - Love my tools. It worked a treat and did a lot of work but recently snuffed it due to a power surge problem - melted the brush housing. No parts avail in Oz, so I tossed it. Still a bargain though for the work it did.

Next part of the project to complete the yard is to lay artificial turf. 6 mtrs x 5 mtrs.
The new generation turf looks the real deal these days. Been watching a local display and the longer it's down, the better it looks. No mowing, watering, fertilising. Dearer up front-yes, but much less hassle longer term.

My pay you to investigate this option.

Regards,

Project 1080.

[sundancewfs]

wear some steel caps, or some stout shoes. Jack-hammers sometimes like to chase your toes around. And try not to fight with it, let it do the work. Oh and dont forget a nice long crow-bar, leverage is your friend.

[astroADF]

Its all a conspiricy by women, They've been at it since Adam was a lad.

It's funny cos it's true :)

Anyway, updates. The weekend didn't go exactly as planned, as in... not all the concrete is ripped up, and a number of key difficulties were encountered. Picked up a jackhammer and sledge from Kennards. 30 minutes into the hammering, I encountered the two things I did NOT want:

- Blue metal (LOTS of blue metal)
- Wire mesh

= I couldn't snap off large areas, but just 'chip away'. The bloke at Kennards also asked if the concrete was old, which it is. I'm assuming that's not going to help the toughness of it. The upside is the concrete is just 100mm thick at best. That's the good news.


Got to around 1300 on Saturday, and I'd barely got into a 4th of the job, and I'd blunted 2 wedge bits to death. So... went back to Kennards, got a larger and (apparently) more powerful breaker. Except the larger breaker? Hardly any difference. Would break off larger chunks, though not necessarily penetrate. So by Sunday morning, frustration was seriously setting in and I've reformulated my plan.


Which is to go at it again next weekend, with TWO of the original jackhammers + a concrete saw to divvy it up into smaller chunks + possible a pneumatic jackhammer; though I'm yet to ascertain if it'll make a real difference? Anyone got thoughts on that choice of additional tools?


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The 3x2 grid to come up. Note the Site Manager assessing the jobsite, and pointing out the lack of OHS endorsed wire. She's such a task master =/

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Tools ready to go! Didn't use the sledgehammer once, unfortunately.

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H-Hour begins; and I find that bloody mesh. Fortunately under the mesh is really good soil, but there's a long way to go.

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The first block is done, mesh removed. Though there's still a lot of redundant concrete to be extracted.

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The bigger breaker arrives. Excited at the time, though disappointed pretty soon after.

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Block 2 of 6 complete. Kind of demonstrates how the breaker didn't have much penetration.

[Tools]

Astro, you are making life difficult for your self. When using a jack hammer you need to start from an edge so that the bits you are breaking off have somewhere to go. Starting in the middle like that means the pieces are locked in and can't break off. I would be getting a crow bar under the concrete and levering it up before hitting it with a sledge hammer. We removed over 40m2 of a drive we needed to patch last week in half a day using this method.

Tools

[Gaza]

dont waste your money or time with a demo saw, just lift with bar from the edge put a wedge in to hold it off the ground and smash with sledgey.

[astroADF]

Yes, the theories are known. The actual practice though? Here's what's stopping those...

- There is no 'underneath' to lift. The concrete is imbedded into loose stone beneath, so there's no smooth slab it's sitting on. It's been poured onto a shale-like surface making it varying depth throughout.

- The area is divided into x6 individual slabs. It matters not where the jackhammer starts, each slab is a unique piece and not bound to the next.

I have some closeup shots of the concrete broken up; I'll post those and you'll see what I'm dealing with.

[Project1080]

Astro,
As you start breaking the surface put a small amount of water into the 'grooves'. Be careful though whilst using electric Jackhammer, When I broke up an old slab, as silly as it sounds, I found the water seemed to soften the concrete. I've been told but never confirmed, it's something to do with the lime content in the concete.

Project 1080.

[astroADF]

P1080, that's a good tip. It's been raining this week and the ground is still damp-ish; hopefully it'll work to my advantage!

[astroADF]

Here's a couple of close-ups of what I'm dealing with; note the amount of blue metal in there, and the rough underneath surface of the chunks.

Also interesting is the green colouring on top; I assume it's paint? Seeped into the surface of the concrete (and thus the green powder everywhere!).

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[astroADF]

Concrete - 0, Rob - 1

Concrete's gone, just need to clean up everything to the skip, grass can follow.

Hard work for the win!

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[Boeing777]

Congrats on your victory! I'm sure your neighbours are as glad as you are that you're done with the jack hammers!

[murray44]

Nice quick weekend job! :D

So once the grass is laid, which end are the goal posts going?

[sundancewfs]

Yes, but the hard work is even sweeter when you look back on the photos, with a cold drink in hand, and think, I did that! Well done.

[phillta]

Good work Rob. What did it cost you in the end, all up? Skip, jackhammers, dumping etc, and how many hours' work? I've got ~50m2 x 60mm to pull up, for which I've been quoted ~$1,200. I suspect once I've paid for all the hire stuff and whatnot and beers for my mates I'll not be far from that figure.

Tim

[astroADF]

I'll do a guesstimate for you...

Time:
x2.5 days over x2 weekends

Cost:
x3 15kg breakers hire @ $89/ea. for 3 days = $267
x1 Heavy breaker for 1 day = about $120
Mini-skip = about $180
Wheelbarrow hire = about $30

Extra equipment, ie: breaker bar / shovels / angle grinder etc I already had.

All up = just under $600

In retrospect?
I didn't need the heavy breaker = -$120
I only needed x1 breaker the 2nd weekend = - $89

So I could have spent as little as around $400.

[Project1080]

x3 15kg breakers hire @ $89/ea. for 3 days = $267
x1 Heavy breaker for 1 day = about $120


Hells Bells!
I reckon an Ozito cheapie from Bunnings at just over $100 would have done the trick. And you get to keep the toy as a bonus.

Usually I look at the buy vs hire price x time use estimate as the decider. 99 times out of 100, I end up buyng a new toy. Next is a new shed as current one is full as a boot with all my toys. Wife has her vices, I have mine.

Project 1080.

[astroADF]

P180, bang on. You can buy exactly the same model from Bunnings for under that cost. And if you wont use it again, you can always ebay it.

Lesson learnt =/ And I've already found places I could use it again!

Flipside is - with a rental, they take care of sharpening your chisels for you; unless you've a grinder to do the job.

[sundancewfs]

unless you've a grinder to do the job.

You could hire one :U

[murray44]

You could hire one :U

I think you mean buy one :U