Odd dpc method or normal?

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So i just want to ask, i have a couple of concerns so i feel the need to ask.

I have a bco inspection due, the lads who have done the brick work have got the structure up. Its all looking good but just a few things in the back of my mind.

At the outside dpc, the dpc strip has drifted slightly towards the cavity. I can see about 10mm of it sticking out inside, about 300mm along the wall. That means theres some mortar bridging the dpc.

They used dpc polythene 'skirts' / tails on the inside skin to tuck the floor membraine at a later date with the screed membraine, i know this is normal but it was layed directly on the brick below without a mortar bed. But they obviously put a mortar bed on top before laying a brick on top. There was no dpc strip like they used on the outside.

Is this anything to worry about. Id like to have seen it be a bed of mortar, dpc strip, polythene tails then a bed of mortar again but they said this is normal and done on new builds?

One last thing. The inner corner on one side the dpc polythene has ripped. Again got the 'its fine' but is it? Can it be fixed?
 
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There should be a DPC internally, as the DPM can't be relied upon on it's own.

Knock the snots off in the DPC in the cavity with a stick or something.

Polythene can be repaired
 
That reply was the kind of reply i knew i was going to get. I knew it wasnt right and should of argued it more.. i guess i just thought i was over thinking it. Thing is you trust someone you think knows more than you.

Its no snots i am worried about. On the outside skin they have used a 100mm wide dpc strip. Part of the strip, say 300mm or whatever long has run out into the inside cavity. So you can see a good 10/12mm overhang looking inside the cavity.

So there definitly should be a reinforced dpc strip inside. The woven looking stuff that has been used outside.
 

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Are you referring to that thing under the course of engineers on the right hand side of the photo? Is that a DPC?
 
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Yes, its sticking out from there onwards. The rest of the course its inline. The dpc they stepped due to floor levels so outside dpc is 1 lower than inside. Personally i would have left them at the same level but they should they couldnt due to tucking the screed membraine with the tails
 
Well is not ideal, poor workmanship, but not really a problem as long as there are no snots on it.
 
Ok woody. So going back to using just a dpc sheet as the inner skin damp, thats still a no-no? Thats my main worry
 
**** poor workmanship.

Lack of DPC to inner leaf is out of order. Misaligning the DPC to the outer leaf is very poor. And personally I always ask for the DPC to be laid on a mortar bed not on bare blocks/bricks but plenty don't bother so you might want to let that one slide.

And what's going on with that cavity batt in the opening reveal? Looks like rats are nesting in it!
 
Iv had to have a dreaded conversation with building control. He did say hes really not happy about it and definitly not ideal. Hes willing to pass it as long as its lapped properly when he visits. All i can hope is we dont get a difference of opinion on physical visit.

I do wish it was done the usual way so i dont have to have this conversation. It could of been avoided
 
I never understand this "it's ok building control will pass it" thinking.

The issue is that building control and the builder wil be long gone when problems potentially start - that's what clients should be concentrating their minds on .... "is the work acceptable to me in the long term?" not to someone who won't be living there, dealing with and paying for issues that may arise.

Ok as a risk based assessment it may well be that DPM might just perform if it's suitably thick, is laid on a smooth bed and not on sharp frogs, and if expansion movement of the wall is likely to be minimal, and the builders other work is generally of good quality. But those are a lot of factors which, combined, can spell danger.
 
I hear you woody. The builder has agreed to change it, but swears blind hes not seen it done another way, unless theres a change in level.

Bco have said its not ideal and prefer the other way but said its unlikley to be a problem. Its crap that theres so many things people do when theres a clear simple way of doing it.
 
but swears blind hes not seen it done another way
I'd not be so sure.

If you have done an apprenticeship or any proper training, then it's drummed into you and it just becomes instinctive how to lay a DPC. And then if any of the manufacturers guides or British Standards or NHBC guides are referred to, it's dead clear about how it should be done.

The way I look at it, and tell the contractors is, if they are coming to me as a brickie, chippie, plasterer or whatever they are telling me that they know their job and I'm paying for that. So I tell tell them right at the start "don't start moaning to me if I pull you up on something that you should know and that I am paying for, otherwise you will be correcting it and I wont be paying for it". And its such a very simple arrangement in my mind, and if something like this DPC thing happens then its either they don't know their job, or they are pulling a fast one and trying to bodge it to say money.
 
I never understand this "it's ok building control will pass it" thinking.

I think part of the problem is people misunderstand the role of Building Control. They are not there as a clerk of works to check quality. They are simply looking after public safety, will it fall down? will it burn down? will it leak heat? etc.

Even so they seem to have a very "light touch" approach theses days so I shudder to think what goes unnoticed.
 

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