Browse Forums Building Standards; Getting It Right! Re: Downpipe Compliance - general discussion 41May 21, 2015 8:00 am Wow, thanks SaveH20. Thanks for the detailed reply. Another forum member is generously going to assist breaking up my PDF file so that I can post the house plan with DP (Down pipe) locations included. If I understand your reply, in my situation even without the 450mm eaves that will increase the roof area considerably as stated. It appears my average roof area as calculated without eaves is the one down pipe (I have 7 as used in this exercise) per 39.3 sq m already and that will only increase to low to mid 40 sq m when eaves added to the area. To comply the correct average area for where I live in Melbourne's north (Wollert) should not exceed 37 sq m per downpipe if the standard gutters and down pipes are used. The exercise used my areas rainfall. So one of two things need to happen if the correct application of the calculation is to comply. I either need larger size gutters and downpipes for the build or additional DPs added. Have I got that correct SaveH20? Re: Downpipe Compliance - general discussion 44May 21, 2015 10:50 am This one here... http://i904.photobucket.com/albums/ac247/goody591/House%20plans_Page_2_zpsweksomox.png If you click on your link above that takes you to your plan hosted on photobucket. On the right hand side you will see a heading called " Share links ". Scroll down until you see the tag IMG then click on the box alongside it with the code inside it. It will then turn yellow and say copied. Paste that line into your post here which will magically show your plan. Stewie Re: Downpipe Compliance - general discussion 47May 21, 2015 12:16 pm goody59 So one of two things need to happen if the correct application of the calculation is to comply. I either need larger size gutters and downpipes for the build or additional DPs added. Have I got that correct SaveH20? Yes, that is correct but it depends more so on the gutter size, not so much the downpipe. The 115mm quad slotted gutter is used a lot because it is produced en masse but it has a small carrying capacity. It will be interesting to see whether Simmonds have specified this gutter for your house. Water flow is fairly complicated as it flows in boundary layers (streamlines) with the core travelling fastest and water on the boundary layers barely moving, the reason why scum builds up on the inside of pipes. The same also happens with an airplane wing, the air on the wing is barely moving, if it was, it would result in boundary layer separation, the mist you see when jets execute 'sharp turns'. Flat bottom slotted gutters have a reduced available depth and this also results in an additional % of boundary layer drag and less flow efficiency, a critical factor unless the downpipes are reasonably close together. The best gutters to use for flow and self cleaning efficiency are the half round but they don't aesthetically suit all houses. I will look at the plans later tonight when I get time. 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: Downpipe Compliance - general discussion 48May 21, 2015 12:39 pm Thanks SaveH20, I will post in this thread again when further details are obtained. I have Title for land in two weeks but Simonds Homes can take soil tests and Land Contour surveys next week before Title in hand with permission already obtained from Places Victoria, the owners of Aurora Estate Epping North/Wollert. Re: Downpipe Compliance - general discussion 49May 23, 2015 11:00 am It appears that you roof drainage will require a gutter with a minimum cross sectional area of approximately 6,000 sq mm for Victorian compliance. This will allow a maximum factored roof catchment area of approximately 45 sq m drained to each downpipe. The average roof area drained looks like being approximately 43 sq m (slope factored). I have looked at the downpipe locations and I have to say that the locations are excellent, certainly far better than the usual unknowledgeable placement that proliferates most new houses in Australia. Your gutters will have high points at the middle of the front and back walls as well as approximately half way between the downpipes. Notice how each downpipe drains a relatively short run of gutter from each side plus there are downpipes close to the larger roof areas. This is in contrast to the usual poor design practice of fitting downpipes to the end of walls for aesthetics...which takes them away from the larger roof catchment areas. The front downpipes are at the end of the walls but the roof areas there are not large...nevertheless, you should not accept anything less than the minimum as required for compliance. 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: Downpipe Compliance - general discussion 50May 23, 2015 12:10 pm I very much appreciate the reply and the amount of time taken to give an expert opinion on my situation. So just one question for the compliance aspect and the calculated minimum cross sectional area of approximately 6,000 sq mm for Victorian compliance, does that compute to using the standard gutters the average Volume builder would use? What size gutter gives that correct calculation? Thanks. Re: Downpipe Compliance - general discussion 51May 23, 2015 1:07 pm Most Victorian new houses are built with non compliant stormwater drainage and most use 115mm quad slotted because it is cheap. There is also a 125mm quad gutter available from some manufacturers. The link below is to an earlier post that shows various Lysaght gutters plus a link to the Lysaght Victorian specification sheet, note how a manufacturer will show the cross sectional area in their specifications. viewtopic.php?p=1273577#p1273577 Also note the trimline slotted gutter with a 6,244 sq mm cross sectional area as a possibility for you to consider but Simmonds may use another manufacturer. It is more than possible that Simmonds will specify the correct gutter to meet compliance, not all builders build houses with non compliant roof drainage but many do. Just wait and see what they intend supplying. The good positioning of the downpipes at least demonstrates that they are aware of that commonly ignored facet of best practice. 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: Downpipe Compliance - general discussion 53May 23, 2015 6:22 pm I wouldn't do that because you don't know yet what gutters they are supplying. I would just ask as to the make and style of gutter and the size and type (metal or uPVC) of downpipe that they will be specifying. It is easy enough to then check the gutter's cross sectional area on the manufacturer's specification sheet. Also, are you having a rainwater tank? You will need 90mm round uPVC downpipes if you do. Round pops have better drainage characteristics than rectangular pops because the round pop presents a larger face towards the flow of water. 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: Downpipe Compliance - general discussion 55May 23, 2015 9:45 pm In Victoria, you are required to have either a minimum 2,000 litre water tank supplied by a minimum 50 sq m roof catchment area and connected to all toilets or a gas boosted solar hot water service as part of the 6 star requirement. Note that if the estate and/or house is also supplied by recycled water, then the above does not apply. Given that you are building with Simmonds and that I have dealt with several Simmonds new home buyers in the past who Simmonds have insisted must have either the rainwater tank or solar hot water option despite being connected to recycled water, if you will also be connected to recycled water, you need to be aware of the above. Note that I have seen numerous Victorian houses with water tanks that were not connected to a minimum 50 sq m roof harvest area. The worst I have seen was a new home connected to a downpipe that serviced 12 sq m of roof harvest area. 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: Downpipe Compliance - general discussion 56May 23, 2015 11:59 pm Aurora where I am building have Estate recycled water to a couple of my outside taps, to my two toilets and one in the laundry. We also have solar gas boosted HWS. We had to achieve 6 star rating. Re: Downpipe Compliance - general discussion 57May 24, 2015 9:10 am goody59 Aurora where I am building have Estate recycled water to a couple of my outside taps, to my two toilets and one in the laundry. We also have solar gas boosted HWS. We had to achieve 6 star rating. As SaveH20 said, everyone has to achieve 6-star rating. Re: Downpipe Compliance - general discussion 58May 24, 2015 9:31 am tlblhayward goody59 Aurora where I am building have Estate recycled water to a couple of my outside taps, to my two toilets and one in the laundry. We also have solar gas boosted HWS. We had to achieve 6 star rating. As SaveH20 said, everyone has to achieve 6-star rating. And I am all for that. I may go down the tank track but at this stage I am having landscaping of drought proof plants, artificial grass and gravel type areas. Melbourne's water is second to none so no need to replace the water we drink. If I went down the tank track I would get the products that SaveH20's Company has, I checked out his products on line and they are cheap top class engineering made for the DIY fers. Re: Downpipe Compliance - general discussion 59May 24, 2015 3:41 pm goody59 Aurora where I am building have Estate recycled water to a couple of my outside taps, to my two toilets and one in the laundry. We also have solar gas boosted HWS. We had to achieve 6 star rating. You are NOT REQUIRED to have either a 2,000 litre water tank connected to all toilets or a gas boosted solar HWS if you are connected to recycled water. Because you are connected to recycled water, it fulfills that part of the 6 star requirement. If for example a customer wanted an instantaneous gas HWS and the house will be connected to recycled water, a builder is wrong in telling the customer that they must have a solar HWS or else a rainwater tank if they want an instantaneous gas HWS. Did Simmonds homes tell you that you must have either a gas boosted solar HWS or a 2,000 litre rainwater tank connected to all toilets to achieve the 6 star requirement? 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: Downpipe Compliance - general discussion 60May 24, 2015 7:52 pm Just thought that people would like to know that the stormwater drainage Australian Standard (i.e. AS3500.3) has been updated... http://www.vba.vic.gov.au/media/latest- ... ail-22-may Building Standards; Getting It Right! It's all good. You can get both wye piece and the coupling with or without thread. The cost difference is negligible and means the plumber only has to carry the single… 1 4921 For anyone that comes across this issue in the future - Just did what aussieta said and found a plumber to inspect it and sign off on it. Was difficult to find someone to… 3 7036 |