Browse Forums Building Standards; Getting It Right! 1 May 19, 2015 6:43 pm Hi, I put this as part of my first post over in the Building a new House forum, but maybe here is a more appropriate spot. We're looking at purchasing a property with the express intention of knocking the existing place down and putting up a new house. The block is a rectangular 15 x 42 metres, and there is a sewer pipe running across the backyard. I've been to the nearest Sydney Water Quick Check agent and confirmed the Zone of Influence runs between 7.7m and 13.7m from the back boundary, as per drawing below: Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ And as you can see the proposed house layout comes up to within about 18cm of the Zone of Influence (although this may get down as low as 9cm). Would this normally pose an issue? Are you able to build right up to the edge of the ZOI? Logic would say yes, that's why it's a line, but not having been through the process I don't know. Any input would be greatly appreciated. Cheers! Re: Building CLOSE to Zone of Influence (not over) 2May 21, 2015 8:43 am Yes you are able to as long as you pier down in that area for your footings so you are past that ZOI. If you have a look at this thread here I have a couple of diagrams that may assist you. viewtopic.php?f=1&t=69324&p=1129658&hilit=concrete+encase+sewer#p1129658 You can actually pier down to within 600mm of the mains sewer but then you have to concrete encase the sewer at approx $1100 per lineal metre to do so - not a cheap exercise. Stewie Re: Building CLOSE to Zone of Influence (not over) 3May 21, 2015 8:46 pm Thank you Stewie D, appreciate the input. If the plans remain the same as they are now, we won't actually be entering the Zone of Influence at all, but will be coming extremely close. I guess I was just wondering whether they get picky about it when approving the plans, the Quick Check place I went said if it's clear it doesn't cross into the ZOI they just rubber stamp it, but if they're not sure they pass it on to a WSC and that can take longer. Maybe we add some additional piering at that end as a precaution or something. Does the proximity to a sewer line have any bearing on trying to do a demolition/build under the Complying Development guidelines? CDC is the only way we can get the house we want, under council DA guidelines the floor space ratio is too large so I'm hanging everything on being able to use CDC. Another question I had was that currently the entire backyard (including over the sewerage pipe and the ZOI) is concreted over, I assume this wouldn't be a problem ripping this up to replace it with just topsoil and grass as part of the whole knock down rebuild process? Thanks again! Re: Building CLOSE to Zone of Influence (not over) 4May 21, 2015 11:18 pm First paragraph , I'll say don't bother. If they say you're out of the ZOI then I wouldn't go spending your money unnecessarily. Secondly, it being there shouldn't affect the demolition of the existing house. Most sewer lines are 600mm - 1000mm deep so as long as the big excavator they use doesn't do anything stupid you should be fine. I'd make sure that the building company has the sewer drawn on your site plan and that it gets sent to the demo firm though. Thirdly, it won't affect it as long as they know as per the previous reasons. Do you know how deep the sewer is ? Edit : I'll answer my own question. Given that they have given you a ZOI of 6m wide and knowing that the angle of repose for most soils is between 30º for softer sand/loam soils to 45º for clays and stiffer soils I'd say that the SWB sewer must be down a couple of metres at least. Unless they have given you that wide easement purely for access?? Stewie Re: Building CLOSE to Zone of Influence (not over) 5May 23, 2015 11:36 am Thank you again Stewie, that's a tremendous help. The sewer is (according to the sewerage diagram included with the contract, if I'm reading it correctly!) 5'2" deep, which lines up with ~1.5m which is what the Sydney Water Quick Check guy told me. This sounds deep enough that it shouldn't be an issue but as you've probably picked up already I like to make absolutely sure of things (especially before forking out for a property!). Regarding why it's so wide, not sure, it may be the soil type possibly? Yes it's a ratio of 2:1 roughly. Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ I have sent the demo company my diagram from my first post above and so they're aware of it, and don't seem to have a problem, the only thing they've said is "you won't be able to build or dig in that area" which I'm thinking is a slightly oversimplified answer, but good enough, because I'm not planning on digging there, just around and "above" there I guess, to remove the pool and the concrete surface. Here is where I can tell the pool is based on Google Maps & SIX Maps: Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Going to try and get more accurate measurements this afternoon in person. Thanks again appreciate your input Re: Building CLOSE to Zone of Influence (not over) 6May 23, 2015 7:22 pm You seem to have all bases covered. A lot of people go into building a new house with their eyes wide open ( or is that firmly shut ) and run into strife. The more homework you do and the more informed you are the better you are able to make decisions. Good luck with it all. Stewie Hi All It has been a few weeks since my last update. The build has been progressing well. No major issues to report. The scaffolding was dropped today, gyprock will be… 96 356758 Hi , I'm currently going through this now within the Whitehorse council which has a similar set of restrictions. We're having to make compromises with our floor plan due… 3 30668 Yes it had a house on it. But Melbourne water only wanted something the original size of the existing house. We managed to fit a 45sq house on. 10 33655 |