Trying to find some specifications DPC

[fraserde]

Hello, I've just had some concreting done which isn't the minimum depth below the DPC. In places it's above it

I've been told by the guy from the local council that it must be a minimum of 50mm when undercover or 75mm not under cover and wouldn't pass a building inspection but I want to show this to the guy who says he's never heard of it.

I've been searching the net and can't find these facts anywhere, I would be really grateful if somebody could point me in the right direction.

Thanks.

[silentC]

It can be difficult to find that kind of information in writing. In lieu of someone having a link, you could try asking the council guy if he knows where it is set down. Or you could try a private building inspector - but it may involve a fee.

Stands to reason that you'd want it below the DPC. I usually try to have finished ground levels at least 100mm below any slab or other spill over point, not that this helps you.

Do you have a contract with the concretor? The only way might be to get it inspected, have it failed, and then go through the legal approach. Could be there's an simple way of fixing it using a waterproofing membrane, but it shouldn't be at your cost.

[fraserde]

Thanks for your reply, I have no contract and I haven't paid any money.

From what I can make out most people want it as high as possible because of the step out from the doors and they may be used to doing it this way.

I used to be in the building trade before emigrating and as soon as I saw it I knew it wasn't right but wasn't sure of the specs here so called the council.

[SAISAY]

'scuse my ignorance, what is DPC???
Wolffie

[fraserde]

'scuse my ignorance, what is DPC???
Wolffie


Damp proof course.

[SAISAY]

Thanks
A day without learning something new is a day wasted :2tsup:
Wolffie

[Make it work]

Hi Fraserde, the guy from the council is spot on and knows the BCA well. It is on page 206, under the heading of Waterproofing of Masonry, section 3.3.4, it is probably available at the local library, possibly in the reference section, if so you can't borrow it, but you can copy it.

I can email you the page if you like, as a jpg file. :)

[fraserde]

Hi Fraserde, the guy from the council is spot on and knows the BCA well. It is on page 206, under the heading of Waterproofing of Masonry, section 3.3.4, it is probably available at the local library, possibly in the reference section, if so you can't borrow it, but you can copy it.

I can email you the page if you like, as a jpg file. :)

Thanks, but there's no need as I phoned back the guy from the council and he was nice enough to photo copy that very page for me.

Hopefully when I show this to the concreter he'll have to agree he's at fault although I wont hold my breath.

Thanks again.

[Brickie]

http://www.concrete.net.au/pdf/HousingWEB.pdf

Page 38

[fraserde]

http://www.concrete.net.au/pdf/HousingWEB.pdf

Page 38


Thanks

[fraserde]

The guy has just come round, the boss that is. He walked around the back looked at it and said it's a lovely job what's your problem? I told him about the minimum depth between DPC and finished concrete, he said it was rubbish I've never heard of it. I showed him the regs, he then said it's rubbish and to go and have a look at other concrete round here and most of them are that height. I said I haven't got to sell those houses.

He then started going on about the crack in my front drive and said I should be more worried about somebody trying to knock money of for that than the back, I obviously said that it had nothing to do with it.

He took some pictures and said he was going to speak to an engineer, still insisting it didn't matter what the regs say.

I asked him why he didn't dig down the two inches required and he said it would have been a lot more work which he hadn't charged me for, yet he'd already charged me for a bobcat to come and clear the old concrete so surely it would have took just one sweep with thathttp://britishexpats.com/forum/images/smilies/confused.gif

[Brickie]

Common sense tells you that by breaching the damp course you will get rising damp in the brickwork above it. :?

[fraserde]

Common sense tells you that by breaching the damp course you will get rising damp in the brickwork above it. :?
He said it runs away from the house, I said what about cappilary
action? He didn't know what that was and said it was rubbish when I explained. I then asked him what he thought the regs were for? I said it's obviously that distance for a reason.

He also argued that because the concrete was levelish with the weep holes any damp would get out ok

[Brickie]

Obviously youre dealing with a dill. :(

[fraserde]

Obviously youre dealing with a dill. :(
The thing is he seemed genuinely surprised when i showed him the regs, he probably does it all the time and has no complaints.

But I guess most people wouldn't know.

[Brickie]

But he should know, Id get get crucified by builders if I didnt know the bricklaying regs.

[journeyman Mick]

..............But I guess most people wouldn't know.

Most people in the building game with half a brain would know you have to keep the ground/slabs/whatever well below the DPC. Sounds like you're dealing with an absolute nong (or a pretty passable actor, who's trying to pull the wool over your eyes) At any rate, tell him as it doesn't comply with the regs you want it redone to comply and that you'll take legal action to recover any costs incurred by yourself in getting him to rectify. Ask him what his address is for service of legal documents, that might wake him up.

Mick

[fraserde]

Most people in the building game with half a brain would know you have to keep the ground/slabs/whatever well below the DPC. Sounds like you're dealing with an absolute nong (or a pretty passable actor, who's trying to pull the wool over your eyes) At any rate, tell him as it doesn't comply with the regs you want it redone to comply and that you'll take legal action to recover any costs incurred by yourself in getting him to rectify. Ask him what his address is for service of legal documents, that might wake him up.

Mick

I realise most people in the trade would know, but most off his customers wouldn't.

I see you're from Kurunda, I was there 10 days ago, tried to see Barron falls but there was a big cloud sitting in front, I was so relaxed and chilled, then came home to this:B.

Beautiful part of the world you live in, stunning.

[journeyman Mick]

You've got to be lucky to see the falls, as there's often cloud or mist in front of them when they're falling and during the dry season (we only have two seasons, wet & dry) thre's no rain, clouds, mist or falls :rolleyes:.

Mick

[autogenous]

picture?

which state? council?

I would say this is a state building by-law

[journeyman Mick]

picture?

which state? council?

I would say this is a state building by-law

He's in Melbourne (see first post). I would be fairly confident that this would be part of the BCA and not a local or state requirement, there's no way the DPC is going to do its job if there's a slab placed higher than it on the outside of the wall. If it's not going to work then the only way that would be allowed is if the DPC wasn't a requirement locally. I can't imagine that there'd be anywhere in Australia (except maybe the great sandy desert:wink:) that a DPC wasn't required.

Mick

[fraserde]

He has definitely breached the code, he still hasn't been back in touch so has obviously washed his hands of it.

Not the worst result in the world as I haven't paid for it and if any problems occur I can always have it cut back a tad away from the house and either filled with some stones or have some of those drains put in.

[fraserde]

After 2 months the guy has just knocked on my door with a report from an engineer which he claims covers me. He says as the engineer says it's ok and has put it in writing then i'm covered.

I think it's a load of bollocks, he claims the engineer says the building code is a guide line and not mandatory so we're not in any danger of it not passing a building inspection.

[silentC]

he claims the engineer says the building code is a guide line and not mandatory
Yeah? Try and tell a building inspector that. He'll laugh all the way to his car to get the red sticker...

However, if you have something from an engineer and it's fair dinkum, they'll probably accept it because it's then the engineer's responsibility when it stuffs up.

[fraserde]

Yeah? Try and tell a building inspector that. He'll laugh all the way to his car to get the red sticker...

However, if you have something from an engineer and it's fair dinkum, they'll probably accept it because it's then the engineer's responsibility when it stuffs up.

I just spoke to the building inspector and he said BCA say that it should be 50mm and 75 mm if it isn't they have to stipulate why it wasn't and have a performance based appraisal.

He also said there is no reason why any perspective buyer would have to accept any performance based appraisal.

[journeyman Mick]

Ask him if he and the engineer would be willing to sign a legally binding guarantee to pay you or any subsequent owners of the house for any water damage (no limit to $$ amount) for the life of the dwelling and for the term of their lives, caused by ingress of water via opeining in question. Gurantee to be legally binding on themselves as individuals, their estates, companies, subsiduaries etc etc etc. See how confident he is then.

Mick

[fraserde]

Ask him if he and the engineer would be willing to sign a legally binding guarantee to pay you or any subsequent owners of the house for any water damage (no limit to $$ amount) for the life of the dwelling and for the term of their lives, caused by ingress of water via opeining in question. Gurantee to be legally binding on themselves as individuals, their estates, companies, subsiduaries etc etc etc. See how confident he is then.

Mick
It's a bloody pain mate, he keeps saying how it would have cost me more if he had excavated the required 2", but then I said to him I didn't ask for a quote for a job and ask for the corners to be cut, I asked for a quote for the job done properly.

[zacnelson]

This sounds like a frustrating predicament!

I just have a quick question, how do you know exactly where the DPC is on the brick wall? I can't imagine it would be sticking out through the mortar? Or did you personally build the wall and therefore can remember which course of bricks it was in? (Please excuse my ignorance)

[fraserde]

This sounds like a frustrating predicament!

I just have a quick question, how do you know exactly where the DPC is on the brick wall? I can't imagine it would be sticking out through the mortar? Or did you personally build the wall and therefore can remember which course of bricks it was in? (Please excuse my ignorance)

I'm just down the road from you in Point Cook.

Yes I can see it, I also no where it is because we built the house (not with my own hands but I watched it)

[davo_scuba]

stick to your guns and don't pay it's not that easy when they start getting agro at you, but you sound like you have got it all under control. hopefully this will make them a bit more careful for all the jobs after you. (think he's trying to pull the wool over your eyes though) you might find that he doesn't own the company and it's all in his wifes or kids names etc so he's got no assets for such occasions that it all goes pear shaped.might be a small win for the normal bloke (trying to get a job you pay for is almost impossible).

[fraserde]

Well yesterday he refused to give me the document from his engineer, and I said I would need it for my wife to take to work. He said why where does she work?

I said at the biggest law company in Australia, he said what would they know about it, I said as a lot as she works in the engineering side of it.

I said that if I researched it with them and the building inspector and it was a legal guarantee that it was indeed down to them i would pay him.

The fax didn't get sent, he claims he'd run out of ink, maybe he has.....

[Brickie]

This sounds like a frustrating predicament!

I just have a quick question, how do you know exactly where the DPC is on the brick wall? I can't imagine it would be sticking out through the mortar? Or did you personally build the wall and therefore can remember which course of bricks it was in? (Please excuse my ignorance)

Sort of explained here. (http://www.brickwork.net.au/Cavity_Flashing.html)

[Terrian]

The fax didn't get sent, he claims he'd run out of ink, maybe he has.....

why does he need ink to send a fax :?

[fraserde]

why does he need ink to send a fax :?

Not sure but he still hasn't sent it.

Again not sure if it's a sign of his dis-honesty or incompetence:roll:

[Terrian]

Not sure but he still hasn't sent it.

Again not sure if it's a sign of his dis-honesty or incompetence:roll:

I go for options 1 & 2 :roll:

[fraserde]

I go for options 1 & 2 :roll:


He also said that half the concrete in Melbourne was poured like that and if everyone expected the BCA to be adhered too, where would we be.

I said I don't really care if 90% is dodgy, it isn't mine. Just because others put up with it why should I?

[autogenous]

Id be checking the other jobs around Melbourne.

If you had photos that would be good.

Is the slab under roof cover?

Is there an under slab membrane such as plastic?

Does that plastic turn up the back of the concrete between the wall and the slab?

Is there fall on the concrete? How much over what metres?

What was the MPA of the concrete?

What does the existing DPC consist of?

How high is the DPC above the ground?

How high is the concrete above the DPC?

If it is double brick and the principles of how cavity water egress is understood, really there should be no DPC course to the outside leaf of brickwork as that is the structure that it exits.

Is the house footings a slab step down?

Photos would be good.

[fraserde]

Is the slab under roof cover? some of it, it goes fromlevelish with the DPC from inside the alfresco to 45mm below outside

Is there an under slab membrane such as plastic? No I believe not

Does that plastic turn up the back of the concrete between the wall and the slab?

Is there fall on the concrete? How much over what metres? Plenty of fall ( the concrete was used to create it, around 2ocm's thick)

What was the MPA of the concrete? 25

What does the existing DPC consist of? Plastic

How high is the DPC above the ground? two bricks

How high is the concrete above the DPC? Levelish maybe a mm or two

If it is double brick. Single

Is the house footings a slab step down? Yes I think.

[fraserde]

The letter from his engineer.





I received from you by email a set of photographs of concrete paving which I am informed was carried out by your company.
The top surface of the concrete had an impressed stencilled pattern and was coloured with a grey pigment.
You have informed me that your client is claiming that the paving does not comply with the Building Code of Australia (BCA) because it less than the minimum distance below the damp proof course (DPC).
The dwelling I was informed was constructed of a timber frame on a concrete slab with a brick outer leaf.
The photographs sent to me show weepholes above the level of the paving.
The BCA in 3.3.4.5 Damp-proof courses - installation (c) (ii) states that DPC should be 75mm above the finished surface level of adjacent paved, concreted or landscaped area that slopes away from the wall.
This section of the BCA specifies the height of DPC above, what is implied here, existing paving, concreted or landscaped area. Also, there is no mention of weepholes being 75mm above the level of the paving.
The photographs received show weepholes. In some instances the weepholes are less than 75mm above the concrete paving.
Weepholes, or open vertical joints, are installed in the outer brickwork to allow water that had entered the cavity between the outer brick leaf and wrapped timber frame to escape. A plastic sheet is then fixed at the bottom to the wrapping material and incorporated into a lower mortar joint between two courses of bricks. The weep holes are vertical openings above that mortar joint which contains the plastic sheet. The vertical openings are between bricks where the mortar to form vertical joints has been excluded.
The plastic sheeting will be considered as a damp-proof course If it complies with other requirements of the BCA. If it's black polyethylene film which is what is used for the plastic film it needs to 0.5mm thick, of high impact resistance and low slip. It also needs to extend through the whole thickness qf the mortar joint.
But if the plastic sheeting acts to remove water from the cavity through the weephole, than it can not be an effective damp-proof course because water running down the plastic sheet to the weepholes is free, in vapour form, to move up the bricks.
This notion is confirmed in part 3.3.4.3 of the BCA, "Cavity ventilation and drainage". Here it states that weepholes must be created in the course immediately above and DPC or flashing... except, (iii), where a damp-proof course is installed in accordance with 3.3.4.5. Therefore, since there are weepholes, it follows that there a DPC is not required.
Firstly, it is not known if there is, in fact, a DPC below the weepholes, secondly given that there are weepholes it follows that there is no DPC because then weepholes would not be necessary if the DPC was done in accordance with the BCA, thirdly a DPC would not be effective, but more importantly, the paving as long as it is below the weepholes does not interfere with the function of the weepholes.
I noted that isolation joints were installed between the paving and brick walls and that saw cuts were placed at appropriate locations. The diagram provided to me shows that the saw cuts were placed at appropriate locations to be functional in controlling the occurrence of shrinkage cracks. I have been informed by you that no shrinkage cracking has occurred. The installation of the isolation joints and the location of the saw cuts (control joints) appear to comply with the guidelines of Australian Standard AS 3727 -1993 Guide to residential pavements.
Given the information I have received including the photographs and diagram and given the requirements of the BCA and guidelines of the above mentioned Australian Standard the paving has been completed in such a way so it does not violate any BCA requirements or Australian Standard requirements and does not interfere with the ventilation and drainage system of the cavity in place,
I trust this information is of assistance to you