Patio Restoration

[Nap.Blownapart]

Gents, I would like to impose on your collective wisdom if I may. The links show some pics of what I would say are some problem areas that I have inherited. I apologize in advance for the length of the post.

IMG0811.JPG (http://www.xmarc.net/dekc/img/CIMG0811.JPG)
IMG0812.JPG (http://www.xmarc.net/dekc/img/CIMG0812.JPG)
IMG0813.JPG (http://www.xmarc.net/dekc/img/CIMG0813.JPG)
IMG0814.JPG (http://www.xmarc.net/dekc/img/CIMG0814.JPG)
IMG0815.JPG (http://www.xmarc.net/dekc/img/CIMG0815.JPG)
IMG0816.JPG (http://www.xmarc.net/dekc/img/CIMG0816.JPG)
IMG0817.JPG (http://www.xmarc.net/dekc/img/CIMG0817.JPG)

The concrete slab as you can see has cracked. I assume it may be in part due to the weight of the columns which appear to be simply built on top of the slab. Shouldn't there be footings of some sort for each column ? I am not even sure there is any reo in the slab. I thought I would have been able to see evidence of that from the edge of the slab. And the cracks right through the slab (as in IMG0812.JPG (http://www.xmarc.net/dekc/img/CIMG0812.JPG)) in some places seem to reinforce that assumption.

Also, from the photo showing what sits on top of the patio columns, I would say it appears there are steel box-beams underneath the rendering, that are now rusting (those unsightly brown water-like stains in IMG0817.JPG (http://www.xmarc.net/dekc/img/CIMG0817.JPG)). Would that be correct ? No doubt there would have been no corrosion treatment applied to the beams. Who was the tossa that thought that was a good idea?

What do you think that brown (resin like stuff - hard to the touch) at the base of the column in IMG0811.JPG (http://www.xmarc.net/dekc/img/CIMG0811.JPG) is ?

The columns are purely an architectural feature, no structural significance. I would like to keep the columns themselves and "rework/render" them, but have no worries about ripping off the crap across the top.

I am not a big fan of terracotta tiles and would like to replace the patio area with pavers (of some type). In order to do so, should i just jack hammer up the whole slab (leaving the columns) and lay on a prepp'ed base or can I lay a base over the top of the terracottas. I can afford to raise the floor level up a further 5cm from the existing level.

Oh, another note: at the far end of the patio (IMG0814.JPG (http://www.xmarc.net/dekc/img/CIMG0814.JPG)), the area is enclosed on 3 sides and hence when it rains, water tends to pool and has subsequently has caused the morter to break up between the house wall and the 1st run of tiles. Maybe they wanted to build a 3-sided water storage tank. Probably more reason for me to hammer up the lot and start from scratch ?

All in all - it looks to me that this particular area was poorly built (or done on the cheap or rushed or all of the above).

Spose I wont see many free weekends any time soon :(

Any advise greatly appreciated.

[johnmurrell]

G'day
that looks a mess

I'm loathe to say it, but, I think the only way to be sure you will have a sound structure there is to knock it all down and start again. Probably not what you wanted to hear, but there appears to be so many things wrong it won't be worth the angst trying to fix them all.:doh:

[silentC]

I think you have a number of unrelated problems there. I'd be surprised if the columns are sitting on that slab. If they are, knock it down tomorrow! More likely, they are on footings and the 'slab' has been poured around them afterwards (let's give the builder some credit).

I reckon you have a tree root under there. Otherwise something else is causing the movement. Erosion perhaps, or poor drainage? That slab is very thin and wouldn't take much to crack it.

The problem with the beam looks like spalling. The steel inside has been exposed to moisture, causing it to rust and expand, cracking the render and causing the rust stains. Hard to say without knowing what the exact composition of the beam is. Are they hollow?

I don't know if there's much you can do to save it. Might be best to just knock it all down. You don't wants bits of render falling on people's heads. Hopefully there's no issues with the connection of it to the house.

[bitingmidge]

Don't guess.

Let me be a bit clearer: DON'T GUESS.

There is no slab, it's the old "lets bung the tiles on a bit of gravel" trick!

So it can go for starters, and even if it was a slab it needs to go.

The beams are probably timber framed with fibro (fibrous cement) over them, and the rust is likely to be where the plasterer used a metal (interior) external angle when he was setting. Welcome to the Gold Coast! :rolleyes:

That's just a guess of course, so take out your hammer and belt a hole in it. Don't worry, you can't do any damage that hasn't already been done, and it won't add to the cost of repair.

Do the same where the columns are cracked. I suspect the columns are brick, rendered but not correctly filled and reinforced. That's OK while there's something tying them across the top, but if that goes, they'll probably just fall over at the horizontal crack line, killing anyone lying in their path.

Don't worry about what the stuff is, it's probably epoxy that someone has stuck down the crack to try to fix it.

Don't do any fix-it work until you've knocked enough holes in it all to work out what's up.

So get out there this arve with a hammer and cold chisel, and take a few pics, but DON'T GUESS what the problem is.

In the meantime, get rid of the slab. This can be done two ways.

The hard way: break it into little pieces with a big hammer, and send it away in your wheelie bit a few tiles at a time, or the easy way; by bringing in a man with a backhoe and a truck for an hour or so. Maybe in such a confined space a bobcat with a backhoe attachment, or a mini excavator would be better.

If you work out how much demolition you need to do, the nice man will take away a whole load of stuff while you are at it!

Take more pics after you've opened it up, then we'll look again.

cheers,

P

[Nap.Blownapart]

Thanks guys for the replies. You've pretty much convinced me that the slab has gotta go. I think I'll whip on down to Kenards and grab a jackhammer.

I'd be surprised SilentC if it is a tree root as this area is at least 20 metres from any (sizeable) tree. There is however an established lillypilly hedge running along side the slab. I'd more inclined to say drainage issues (the soil here is mostly clay) in combination with a poorly built (or cured) slab.

As for the columns, the hammer and investigative chisel are coming out for a peek. I am going to get a mate in to rip off the rusting/rendered stuff on top of the columns with his crane.

I'll post some pic's after the demolition.

Should another slab be poured or is a packed roadbase,crusherdust prepp'ed bed fine for the area to be paved ? It will be a high traffic area.

Thx again for your comments. Great forum :2tsup:

[silentC]

It may be an optical illusion, but it looks as if the corner has lifted a bit, which made me think something was pushing it up. But then, if it has slumped in the middle where the crack is, that could happen too. Err, has that first column got a lean on it?

But we mustn't guess else we'll incur the wrath of the biting one, so we look forward to seeing your pictures and reading the gruesome details.