Tiling project - advice sought

[schlitzaugen]

The Roman concrete made with Tuff ( volcanic rock crushed finely ) would also set underwater, so good for piers etc. And was bloody tough and long lasting, a good example being the Pantheon in Rome

a

Or the feet of roman bridges built across the Danube in Europe, still standing today.

Seasink, I am just about to have my shed slab poured, what should I ask/keep an eye on to avoid the problems/shortcuts you described above? It is going to be 20cm thick reinforced.

One possible cause I didn't see mentioned in relation to "concrete cancer" might have to do with the salinity of water here. When that starts creeping through concrete, I wouldn't be surprised if it killed the reinforcing steel. I am not sure slabs here have any waterproofing. Tar was used overseas some decades ago.

 

[seasink]

Do you have a professional design for the reinforcement, which will also show cover for the steel in accordance with the standards? Cover is critical. If there is to be a hoist or heavy point load mention that to the designer.

The designer will nominate a sensible 28 day strength for the mix, not something with minimal cement suitable only for footpaths. The slump will be specified, so don't go watering it way down on site. Don't go to lunch half way through. I think a 200 slab needs vibration when placing - the concretor will own the tool. (The building industry has never heard of centimetres, only mm and occasionally m. All your slab's dimensions will be measured in mm)

When the surface is trowelled don't use chlorides - I saw someone doing this recently. The steel is protected by the alkalinity of cement and the density of the slab. And do use a waterproof membrane; they are cheap protection. I presume the foundation is Perth sandy. Support the reo on bar chairs, and stop the legs piercing the membrane by putting lids under them. Many concretors will use mesh and lift it up during placing to save labour time. This makes cover hard to achieve or assess. Engineer designers will usually use steel bars on chairs. You can get all the bits and pieces with the steel, including tie wire.

Cure the thing! That is keep it wet so that it can hydrate and harden correctly on the surface. For a garage you can put wet sand on it or put a hose under some plastic. Get out with a hose and don't be in a hurry to start building.

Think about how you are going to hold stud walls down. Cavity brickwork requires a slab set down at the cavity.

All this info and more can be found online. I can't get detailed here being long out of this.

 

[Whippet]

Hi.

My uniformed comment.

I don't know what sort of shed you are constructing or what loads the floor will be carrying.

If you are constructing a domestic garage or suburban shed, it seems to me that a 200mm depth of concrete floor might be more than is needed? Maybe the sand foundation is what is driving the 200mm depth?

I think seasink has made some important comments above, but I don't know how in a domestic situation the salient points are controlled on behalf of the owner during supply and laying. You only get once opportunity to get it right with concrete.

Cheers.

 

[Greenpeace]

Millimeters for slabs must be engineer talk, every concreter I've met talks slabs in inches, "4 inch slab", "6 inch slab", etc. They will talk piers and footings in mm though.
Unless that's just a QLD thing.

 

[seasink]

It's an age thing. I do it too, but off a building site.

But for 50 years now it has been compulsory to use millimetres to dimension building works. When they noticed back then how reluctant we were to convert they banned the sale of foot and inch tapes, rules etc. They are now available again, but you won't see them on a site.

Concrete is ordered from the batch plant in cubic metres.

 

[bluey504]

Happy Anniversary! 2024 is The Big 50 of a metric Australia.
Just hope the dwindling Old School of Cardigan wearers catch up before they die.
The young Lads at work have NFI what 8' of 4"x2" is when a Crusty turns up. I laugh a lot, out loud, when they start asking about products they are legally not allowed AKA Creosote....
This is probably why most of Dad's brothers and Sisters died from Cancer, Dad included...GrandPa Joe worked as a ganger for Vic Rail using Creosote to prevent termites/wood rot etc.
Not the most positive post but I just need a little venting, hope you can understand.

Brendan.

 

[seasink]

I got some creosote before it became so hard to get. Just the thing for white ants attacking poles in the ground. I am very very careful.

50 years ago every drawing board had metric conversion tables taped on it. Some had metric brick rods as well. It really slowed work down at the time, as very few people could imagine in millimetres. Even fewer in kiloPascals and kiloNewtons. I still have several well thumbed conversion books. There were some holdouts - I had design work on one of the very last major projects built in the old units.

It wasn't entirely successful, as the SI enthusiasts forced 300 modular things which the world didn't want (eg fluorescent tubes world wide are in inches). Plumbing stayed in imperial, but used nominal rounded metric descriptions instead. The same happened for doors. Bricks just carried on in inches, thankfully. Imagine doing alts and adds if they had changed. I have a tiling job at home which is trouble - the existing tiles are 6 inch. That is not the same as 150 and the joints differ..

A surprising number of European standards can be converted neatly into inches.

 

[Greenpeace]

Happy Anniversary! 2024 is The Big 50 of a metric Australia.
Just hope the dwindling Old School of Cardigan wearers catch up before they die.
The young Lads at work have NFI what 8' of 4"x2" is when a Crusty turns up. I laugh a lot, out loud, when they start asking about products they are legally not allowed AKA Creosote....
This is probably why most of Dad's brothers and Sisters died from Cancer, Dad included...GrandPa Joe worked as a ganger for Vic Rail using Creosote to prevent termites/wood rot etc.
Not the most positive post but I just need a little venting, hope you can understand.

Brendan.

Oh I'm hearing you, anyone that uses measurements other than metric should be burned at the stake.
The young lads are the same that I know, going on about their 4WD utes, with their 3 inch lifts and 35" tyres on 15" x 10" rims. Then they start on about how their turbo diesel has a 3" exhaust, 20 pounds of boost and makes 250 HP at the back wheels. One guy said his Hilux had a 1.8 second 60 foot time and ran a 13.9 at 98 mph over the 1/4 mile. I haven't seen a time slip to prove it though.
Then there's their stereos with 6 1/2" splits in the doors, 6"x9" rears and 12" sub woofers.
They've all got 12,000 pound winches on their bullbars, but will probably never use them. The hardest work most of those utes would do, will be when they have a 10 foot tinny on the roof rack. One guy has a 15 foot fishing boat with a 75HP Mercury outboard. Late time he went out he got fined for doing 20 knots in a 10 knot zone. Apparently he got that sh#tty he threw his favourite 6 foot rod over the side, one of the other boys said he'd just rigged it up with some 20 pound line, a size 5 sinker and a 4/0 hook.
I'd rather go duck hunting with my trusty 12 gauge than go fishing. It is a combo gun though with a .22 barrel underneath, in case I see a stray hare or some such.
Oh and one guy is also into horses, has a couple of 16 hand standard breds that he drags around in a double horse float. I think he said he uses a 17" saddle with 4 1/2" knife edge stirrups, but I was only half listening.
He was having trouble blowing tyres on the float, but said once he started putting 40 psi in them instead of 30 psi, (with his 3 CFM compressor that he bought at Supercheap), problem solved. Then the lads are all into Snap-on tools, the price they pay for a 1/2" drive ratchet is unbelievable. I'd rather spend the money on a decent 4" angle grinder. Or I suppose I could put the money towards a new 23 HP Victa zero turn with a 46" cut that's on sale at Bunnings.
Sometimes they make me want toe them up the ar#e with my size 10s. I suppose if I wore leather gloves I could take one off and slap them up the back of the head with a size 7.
I don't stress too much though, they can have their Quarter Pounders from McDonalds for lunch, I prefer to eat healthier and usually grab a foot long at Subway. My only vice is the odd 16 ounce flat white at Zaraffas.
We're going on holidays soon, catching an A380 Airbus. Can't wait to feel the 280,000 pounds of take-off thrust from those RR Trent 900s, get up to 37,000 feet, and start cruising at 450 knots.
I'd rather spend the money on a new 80 inch TV, but Mrs G wants to go jetsetting, maybe she wants me to join the "mile high" club with her.
All in all though, I'm just glad I live in QLD where we don't ask for a beer in a pint glass like some other states.
We do still have a 3' 6" rail gauge up here though, thankfully some Muppet hasn't come along with a metric tape and decided to round it off to a neat metre, that could end up a little messy.

 

[bluey504]

Oh I'm hearing you, anyone that uses measurements other than metric should be burned at the stake.
The young lads are the same that I know, going on about their 4WD utes, with their 3 inch lifts and 35" tyres on 15" x 10" rims. Then they start on about how their turbo diesel has a 3" exhaust, 20 pounds of boost and makes 250 HP at the back wheels. One guy said his Hilux had a 1.8 second 60 foot time and ran a 13.9 at 98 mph over the 1/4 mile. I haven't seen a time slip to prove it though.
Then there's their stereos with 6 1/2" splits in the doors, 6"x9" rears and 12" sub woofers.
They've all got 12,000 pound winches on their bullbars, but will probably never use them. The hardest work most of those utes would do, will be when they have a 10 foot tinny on the roof rack. One guy has a 15 foot fishing boat with a 75HP Mercury outboard. Late time he went out he got fined for doing 20 knots in a 10 knot zone. Apparently he got that sh#tty he threw his favourite 6 foot rod over the side, one of the other boys said he'd just rigged it up with some 20 pound line, a size 5 sinker and a 4/0 hook.
I'd rather go duck hunting with my trusty 12 gauge than go fishing. It is a combo gun though with a .22 barrel underneath, in case I see a stray hare or some such.
Oh and one guy is also into horses, has a couple of 16 hand standard breds that he drags around in a double horse float. I think he said he uses a 17" saddle with 4 1/2" knife edge stirrups, but I was only half listening.
He was having trouble blowing tyres on the float, but said once he started putting 40 psi in them instead of 30 psi, (with his 3 CFM compressor that he bought at Supercheap), problem solved. Then the lads are all into Snap-on tools, the price they pay for a 1/2" drive ratchet is unbelievable. I'd rather spend the money on a decent 4" angle grinder. Or I suppose I could put the money towards a new 23 HP Victa zero turn with a 46" cut that's on sale at Bunnings.
Sometimes they make me want toe them up the ar#e with my size 10s. I suppose if I wore leather gloves I could take one off and slap them up the back of the head with a size 7.
I don't stress too much though, they can have their Quarter Pounders from McDonalds for lunch, I prefer to eat healthier and usually grab a foot long at Subway. My only vice is the odd 16 ounce flat white at Zaraffas.
We're going on holidays soon, catching an A380 Airbus. Can't wait to feel the 280,000 pounds of take-off thrust from those RR Trent 900s, get up to 37,000 feet, and start cruising at 450 knots.
I'd rather spend the money on a new 80 inch TV, but Mrs G wants to go jetsetting, maybe she wants me to join the "mile high" club with her.
All in all though, I'm just glad I live in QLD where we don't ask for a beer in a pint glass like some other states.
We do still have a 3' 6" rail gauge up here though, thankfully some Muppet hasn't come along with a metric tape and decided to round it off to a neat metre, that could end up a little messy.

Oh you are terrible Greenpeace, but I like you!
Yes there are so much ingrained Imperial/SAE that it has become functional in a rational way. Ratchet drives sizes and wheel diameters are best in this 'cut and dried' fashion because it works(?).

Brendan.
ps If you cross a Police song with a Monty Python sketch; 'Every Little thing she does is Magic'/'Burn the Witch!'.