Browse Forums Building Standards; Getting It Right! Re: Damp proof course 41Feb 27, 2014 10:29 am Hi Lex, The stormwater pipes aren't buried deeply enough. Near the ORG they are buried about 20mm below where finished ground level should be and near the downpipe that was cut, they are at ground level. The ground levels were never right and didn't comply with the BCA. Re: Damp proof course 43Feb 27, 2014 11:15 am ORG is overflow relief gully. It is an outlet in the ground outside your home designed to act as a release valve if there is a blockage in your plumbing. It needs to be 150mm below your lowest household drain - usually the shower drain. This is so, in the event of a blockage, the sewage will spew out into your backyard where it is easier to clean up than if it spews up into your house! The downpipe wasn't cut - that was my mistake when I saw the water gushing out. It was the stormwater pipe it is attached to that was cut - in two places actually. They weren't buried deeply enough so when the concreter cut up the concrete he had laid on top of them with a demolition saw, the saw went straight through the concrete and into the pipe. I can't blame him. The builder should have made sure the pipes were buried deeply enough. But he didn't. Instead he just covered them with dirt and then refused to admit that he had left the wrong ground levels around the house. Also - another important point - there is supposed to be 75mm between the top of your ORG and ground level. Once you allow for that separation in our case, you get pipes under 20mm of soil. Re: Damp proof course 44Feb 27, 2014 12:01 pm Hi Liliana, It is legal to use the flimsy 90 mm PVC storm water pipe rather than 100mm DWV pipe when there is a charged system but the better plumbers will use DWV. If the plans say 90 mm PVC storm water pipe, then the plumbers are not going to use and pay for the better DWV pipe out of their own pocket! EDIT: I have deleted my previously posted stormwater pipe size calculations due to AS/NZS 3500.3 Section 5 5.5 allowing plumbers to determine stormwater pipe design on urban allotments with less than 1,000 sq m in area by using "local practice and experience". 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp proof course 45Feb 27, 2014 12:11 pm Oh, thanks I don't know if we have the ORG then ... ... we do have some "access" thingy (covered with those plastic covers like a very large mesh) and that pipe goes straight down right to the ... well now I am not sure if it's the stormwater pipe or the sewage pipe!!! but anyway, the pipe that is placed under that little removable cover goes vertically down to the swtr/sewage(?) pipe which is about 60cm below the ground level. Is that it? But it's right up against the slab, so it does not make much sense to me because it would then overflow right around the slab, maybe under it as well. Oh hang on ... we do have anohter thing left like a mushroom sticking in our lawn which they call "sewage inspection?? access" or something like that. It is closer to the easement access pit which is at the back corner of our backyard. That pipe+cap thingy was supposed to be cut to the ground level (after landscaping), but we still haven't done it because the original plumbing "experts" glued the (otherwise) removable top, so now it's a much bigger job to take it down to the grass level. He apparently had the option of either glueing it or just attaching/screwing the top. Of course, he chose the option which is worse for us. My signature is distracting people from my wise posts ... Re: Damp proof course 47Feb 27, 2014 12:29 pm Hi SaveH20, Our plans say 100mm DIA Class 6 UPVC stormwater pipes. So should we have a DWV pipe even if it is no longer part of the charged system? What do you mean by "plus the additional gutter area"? Re: Damp proof course 48Feb 27, 2014 12:58 pm Hi Liliana, Thanks for the curve ball. Liliana Our plans say 100mm DIA Class 6 UPVC stormwater pipes. Class 6 pertains to PVC pressure pipe and what's more, they do make PVC class 6 pressure pipe in 100 mm. You can discount them requiring class 6 PVC pipe. I think that the plans have mixed up PVC storm water pipe, PVC pressure pipe and PVC SN6 DWV pipe. They probably mean 100 mm PVC SN6 DWV pipe even though the plans (also) state storm water pipe! Liliana So should we have a DWV pipe even if it is no longer part of the charged system? If the roof area drains more water than the compliance calculations allow 90 mm PVC storm water pipe to drain, then you must have larger pipe. Note that I thought that your pipes were 90 mm PVC storm water pipes but your plans say 100 mm (let's forget about the rest of their description!). What size are they? Liliana What do you mean by "plus the additional gutter area"? The roof drainage area is measured to the outside edge of the gutter. The guttering must be included in the roof area when doing compliance calculations. 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp proof course 49Feb 27, 2014 1:15 pm Hi SaveH20,
Nothing would surprise me anymore about our designer's incompetence. Apparently she even has illegal box gutter section drawings on the plans as well. I'm just going out to do a little digging. To measure the gutter, do I just measure width by length and factor that in? No, just reread your post - just width should do it. Re: Damp proof course 50Feb 27, 2014 1:26 pm The pipes that I can see are 90 and they are definitely not DWV. The gutters measured from the fascia to the outer edge (from underneath) are between 12 to 13 cm. But our roof pitch is 22.5 so what multiplier do I use? Re: Damp proof course 51Feb 27, 2014 1:36 pm Don't worry about it, not worth your trouble as the roof plan area will be close enough but the guttering is usually drawn on the plans. If the roof area is borderline, then we can include the gutter area. The roof has to overhang by at least 50 mm and the gutters are probably 125 mm. Do you know the roof pitch? If you want to PM me your roof plan area and pitch, I will PM back the factored area. The pipes are exposed but you might have to scrape away a bit more dirt to see some writing. Very interested to see what the plumbers used! It sounds like the designer hasn't used a storm water drainage professional and has done it herself. A professional would not have mixed up 3 different PVC pipes. Class 6 storm water pipe...now that's a classic!!! 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp proof course 52Feb 27, 2014 1:39 pm Liliana The pipes that I can see are 90 and they are definitely not DWV. Ok!!! Interesting! Liliana The gutters measured from the fascia to the outer edge (from underneath) are between 12 to 13 cm. But our roof pitch is 22.5 so what multiplier do I use? Add 70 mm for the gutters. 1.21 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp proof course 53Feb 27, 2014 1:41 pm I've dug away quite a bit of dirt but can't find any writing. I have measured it compared to the rainwater tank pipe which I know is 90 and I am pretty certain they are 90. I'll scan the roof plan but it will be in two parts- two big to fit on A4 screen.
We seem to be writing at the same time - we are in parallel universes. Re: Damp proof course 54Feb 27, 2014 1:51 pm I've sent an email with the roof plan but it doesn't say area and that is probably what you need. The area is 168.7sqm. Do you mean add 70mm or 70m? Just using roof area without gutters I get 441 lpm. That means DWV, doesn't it? Re: Damp proof course 55Feb 27, 2014 2:25 pm The Email hasn't come through yet. If the overhang is 50 mm and the gutters are 125 wide, you add 75 mm. It doesn't matter though as the 441 lpm calculation you did for the roof area alone is correct. EDIT: Previous calculations deleted as they are not required as per AS/NZS 3500.3 Section 5.5 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp proof course 56Feb 27, 2014 2:28 pm Okay so only if a single pipe drains the property. Well, in fact we have two. One on the north side and one going under the slab in the garage. Yes, I'll check with the VBA. There is an inspector who has been assigned to check the plumbers work; I can ask him. Re: Damp proof course 57Feb 27, 2014 2:34 pm If there are 2 pipes, then it is compliant. It should be regulatory for DWV pipes to be used with charged systems but DWV pipes are also not pressure rated! Any self respecting plumber will use them and the VBA prefers it. How can there be a pipe going under the garage when all of the downpipes in that area are charged and flowing the other way? EDIT: I remember from the tank thread that it was never determined where the tank overflow went. 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp proof course 58Feb 27, 2014 2:41 pm Apparently this drains to the front.
Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ It is situated behind the garage. I don't know why it is there but it is handy because we are going to pipe the tank overflow pipe to it. Re: Damp proof course 59Feb 27, 2014 2:46 pm But if nothing currently drains to it, then the drainage at the moment is through one pipe only and not compliant unless the tank drains to yet another pipe somewhere. My head hurts! 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp proof course 60Feb 27, 2014 2:49 pm No, then it definitely is not compliant at the moment. Your head hurts! I've spent the last year and a half trying to make some sense out of the mess here. I might as well have built the place myself. Then I wouldn't be surprised at the result. Have look at your house plans and you will probably find that brick articulation joint has been missed. Maximum allowable spacing is 6M or 5.5M for a wall with window… 17 20579 Hi all Am new to this forum. I want to get some ideas/info about how to manage an 80 year old factory restoration to convert to a residence. The factory floor is concrete… 0 6342 Hi We have a road close to our place and only an old flimsy wooden fence between us and the Neighbour closest to the road. Any ideas on a sound proof modular fence. Like… 0 7472 |