Browse Forums Paving & Concreting Re: Concrete Perimeter around home 83Jul 28, 2016 10:47 am 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: Concrete Perimeter around home 85Jul 28, 2016 11:56 pm Very low weep holes also provide termite access but you have covers anyway. It would be a much bigger problem if it was soil and not concrete. The ORG level will be a difficult problem for the concreter. From the photos, required site drainage during construction was ignored and the concreter is just the builder's whipping boy. Cracking is the result of either movement...be it an earthquake or whatever and/or poor workmanship. Just remember that no major problem/cause has been found yet, for now it is investigate, learn and monitor. Compliant building materials are suitable for a range of conditions. Of interest, the excerpt that Liliana cut and pasted in her last post was from the MBA submission to an inquiry on non conforming products. The submission also detailed the very serious Infinity Cables debacle...up to 250,000 houses fitted with 4,000,000 metres of non conforming electrical cable that becomes brittle within a few years that can then cause shock or fire if disturbed. 2016 onward are seen as critical years. There have been many other non conforming products used over the years and the importance of having the services of a suitably qualified private building consultant who is also aware of such issues cannot be overstated. 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: Concrete Perimeter around home 86Jul 29, 2016 8:18 am SaveH2O Just remember that no major problem/cause has been found yet, for now it is investigate, learn and monitor. Thanks SaveH20, I have engaged the services of Building Expert to come and inspect the property so hopefully he will be able to help me further. I have also talked to a few forensic structural engineers who were happy to give me some advice given the situation and they were quite surprised about the cracks I was telling them as the house is only 4 months old. They have recommended to do the following: – a soil test to confirm the original site classification. – an independent assessment of the original engineer’s design. – a review of the site inspections carried out during construction. – recording of floor levels and crack widths as a datum for future movement. – a review of the weather patterns in the four months before and after your slab was poured. – a look at historic aerial photos to see if your house is built over any natural features such as trees or creeks or dams. – a plumbing test to see if your pipes are leaking or have been affected. – measurements if the as- constructed slab beam depth and slab thickness Re: Concrete Perimeter around home 87Jul 29, 2016 9:03 am A good list and the one below is excellent. jennifer_sml – a look at historic aerial photos to see if your house is built over any natural features such as trees or creeks or dams. Building expert has all of the right qualifications and experience, you are in good hands. It might also surprise you to learn that anyone can set themselves up as a building consultant in Victoria yet many new home buyers only check the prices and not the qualifications. Plumbers also sign off on their own work. Enter Truganina and the radius (I suggest within 10 km) to access data from all of the weather stations in your area. http://www.bom.gov.au/climate/data/stations/ http://www.bom.gov.au/jsp/ncc/cdio/weat ... num=087031 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: Concrete Perimeter around home 89Jul 29, 2016 5:28 pm Your local weather station probably won't have the long term average monthly rainfall but the Melbourne average is readily available and can be used as a reference against the actual rainfall. Most people would just use the Melbourne figures and these are readily available. I think that Melbourne had less than 10mm in February from memory. The amount of rainfall doesn't cause heave, it is the reactive clay absorbing water and expanding upwards that creates lift. Hydraulic lift is very powerful and heave can easily exceed twenty times the force of the house footprint per square metre. For clay to expand, the water needs to reach it and water flowing off a large roof area through an unconnected downpipe pop will deposit water off a large area to a small area. In other words, if there was 10mm of rain and the gutter pop diverted water off 40 square metres of roof to an area of 2 square metres, then how much rain actually fell on that small concentrated area? Your path was designed as a swale, a negligible amount of water would pass through the expansion foam between the wall and the path. Comparing any effect the path may have had on the sub soil moisture levels to the effect of not having the required site drainage during construction for a house built on highly reactive soil doesn't even approach apples and oranges. It would be an idea to take some photos of the path that show the swale...perhaps lay a straight edge across the path to show the gap. 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: Concrete Perimeter around home 92Jul 29, 2016 7:10 pm SaveH2O Your path was designed as a swale, a negligible amount of water would pass through the expansion foam between the wall and the path. Comparing any effect the path may have had on the sub soil moisture levels to the effect of not having the required site drainage during construction for a house built on highly reactive soil doesn't even approach apples and oranges. So although my concrete perimeter path is level the amount of water that would pass through the expansion foam between the wall and path is nothing compared to having the proper site drainage during construction? Also, I see the builder we have used has not put temporary downpipes on homes they are building around the area or graded a slope away from the home either. I think it would be safe to say they did the same to our build too. Re: Concrete Perimeter around home 93Jul 29, 2016 8:17 pm jennifer_sml So although my concrete perimeter path is level the amount of water that would pass through the expansion foam between the wall and path is nothing compared to having the proper site drainage during construction? IMHO...yes. I don't think that it is absolutely level going by the placement of the drains plus there is a lip on the boundary edge and the photo with the spirit level also shows a slight slope away from the house. Does a straight edge lay level with the surface when you lay it across the path? Ask the concreter about it when you see him next. The amount of water that could possibly seep through the expansion foam would be miniscule when compared to what downpipe pops can dump over small areas next to the foundation. jennifer_sml Also, I see the builder we have used has not put temporary downpipes on homes they are building around the area or graded a slope away from the home either. It would be a very good idea to take photos of those properties too. See if you can get some good shots of the slab's perimeter as well as the tell tale missing temporary downpipes but try to have some distinguishing feature in the shots for later identification. It doesn't take much rain for downpipe pops to create a quagmire on un-sloped highly reactive soil. 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: Concrete Perimeter around home 94Jul 29, 2016 8:33 pm What month did the roof go up? 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: Concrete Perimeter around home 95Jul 29, 2016 8:36 pm SaveH2O jennifer_sml I don't think that it is absolutely level going by the placement of the drains plus there is a lip on the boundary edge and the photo with the spirit level also shows a slight slope away from the house. Does a straight edge lay level with the surface when you lay it across the path? I laid the straight edge along different points of the foot path and most of it is level. There is a small lip on the boundry edge and I can see the concrete has pulled away from the fence leaving a small gap. There are 2 sections which I know it does slope towards the home a bit. From the side view the the concrete is sloped towards the trench drains. I went outside this afternoon when it was raining and saw one patch where a small amount of water did pond against the home (that was where the concrete sloped towards the home). But for everywhere else, the water seemed to be running to the drains. I went out again 15 mins after it stopped raining and the small amount of water where it sloped against the home was still there but did not see any water pond against the home. The areas where it slopes towards the home is also partially covered too under the main roof. Re: Concrete Perimeter around home 97Jul 29, 2016 9:04 pm January was the wettest month since June 2012. 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: Concrete Perimeter around home 98Jul 29, 2016 9:23 pm SaveH2O January was the wettest month since June 2012. Oh no, from the end of December till nearly the end January the house was not worked on as it was holidays, hence that's why down pipes only went up end of January I suppose. On the 29th January I went out to the site to meet a the fencer and I remember him commenting when he walked around the boundary to quote he felt like he was walking on quicksand as he was trying to get the mud piled up on his shoes off on the side of the pavement afterwards. The concreting went down 2nd week of March. There were a few cracks already at the beginning of March when we came for settlement inspection but was assured they were just movement cracks and very normal and there would be more so it would all get taken care of during 3 month warranty inspection. Ever since we moved in there have been more and more cracks but never really thought much of it. I mean our ss came over so many times between our settlement and warranty inspection to fix up little bits and pieces and never said anything apart from comment how good the concrete looked. Even upon our warranty inspection the warranty inspector said our concreting looked good and all the cracks were normal. It was not until I showed him one crack (which was the very first crack we noticed appeared before our settlement) that I was concerned about that he said he would send his structural engineer in. And that's how we got to this point. Me, spending day and night, restlessly, sleeplessly thinking about our how this could be happening! Re: Concrete Perimeter around home 99Jul 29, 2016 11:50 pm jennifer_sml No the land belongs to an estate company who we also bought our land from. Ok, make sure you keep an eye on it. If you decide to take photos of your builders other sites, try and get his signage in the shots too. And the cracks inside your home or outside etc, document those, take photos with a ruler next to the crack, date, what area etc. Re: Concrete Perimeter around home 100Jul 30, 2016 1:12 am jennifer_sml On the 29th January I went out to the site to meet a the fencer and I remember him commenting when he walked around the boundary to quote he felt like he was walking on quicksand as he was trying to get the mud piled up on his shoes off on the side of the pavement afterwards. Melbourne had rain that day, do you remember if there were large puddles pooling next to the slab? It is best if you jot down all of these little memories and make a time line. January's rainfall, supercharged by the roof drainage to concentrated areas, will be a focus...no doubt. Sub soil moisture samples are taken at different depths from different areas and compared. London to a brick that your moisture levels will be highest near the downpipes. I posted earlier that you needed to have the drainage pipes examined (camera) but I no longer consider these to be a suspect given the time frames and your short residency. Clay trench plugs however are a critical mandated requirement on reactive soils as per AS2870 and so the pipe trenches will need scrutiny if the cracks worsen and heave is recognised during the monitoring period. Hopefully your situation doesn't escalate to that. jennifer_sml Even upon our warranty inspection the warranty inspector said our concreting looked good and all the cracks were normal. It was not until I showed him one crack (which was the very first crack we noticed appeared before our settlement) that I was concerned about that he said he would send his structural engineer in. Who exactly was this "warranty inspector"? 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Yes, unless you are in a low intensity rainfall area or the area is protected from rain. Do you have access to NCC Part 2 or can you download it? I can email you a copy… 10 12916 i had the my concreters concrete right up to the fence. I have pits all along my path, so the water tends to drain away from the house and into the pits. There's only one… 7 13226 Grab a hose, insert it at the top of the inlet/down pipe and turn the water on and see where the water is escaping from. Then you'll know. 3 8810 |