Browse Forums Building Standards; Getting It Right! 1 Oct 07, 2014 2:43 pm This is one huge topic and may need a forum all of its own... but here goes anyway. I think it was time that the public knew. Are you building in an area where the soil is highly reactive clay? If so you might do well to find out everything you can on the topic so as to avoid heave or extreme shrinkage... or both. To put it simply you may need to spend considerably more to ensure that your slab performs adequately. Soil classifications such as P, H1, H2, H3, E can require an enormous amount of care so that your houses do not have serious structural problems later on. Even MD can be a problem as can a knock-down / re-build done too quickly... because where a house has been removed recently there is a dry soil area where the house footprint once was. Another problem can be droughts, particularly long-term droughts which we have just finished enduring 5 years ago. Then there are large trees removed recently and the planting of trees that will become large in the future to consider. There is also a great need to consider all drainage aspects of the site, sometimes in great detail. As I see it, the main problem is keeping the public aware of the possible problems and the end of their reliance on people who are not caring enough. The players involved in the final result are the Owners, the Building Surveyors, the Soil Report Writers, the Structural Engineers, the Architects / Draftspersons... and of course the Builders. When you have articles in the newspapers such as appeared in The AGE on June 8th... 'Thousands of Home Owners Facing Ruin' where the reporter stated that thousands of waffle pod slabs were failing... you begin to wonder how many of the abovementioned people cared enough to ensure that those homes with such slabs would be adequate in the long-term. It may have been most or all of them. (Everyone's heard the saying 'A chain is only as strong as its weakest link'.) Well thousands of homes are apparently not able to cope with the forces of heave and settlement in the short-term, let alone the long-term. So I thought it might be time to get this out in the open. Were the recommendations in the soil reports for instance followed to a tee. Any why are they only recommendations and not requirements. Perhaps a bit of extra legislation is needed to make certain that soil reports are followed right down to their last recommendation. And yes of course it will cost more in these problem soil areas, but it's surely worth it. There will be the need for bored piers, possibly concrete aprons, more agricultural drainage (hopefully not by owners), stronger slabs--- or slabs might not be appropriate at all perhaps. Now there's a thought. Perhaps timber floors are more suited to potential heave than slabs? And I believe there are maps of some areas that show where trees once were. They would be worth their weight in gold. Anyway I'm just offering this as a start to what might become a huge awareness campaign in problem soil areas. Leonardo_23 Re: Are you building in a problem soil area? 2Oct 07, 2014 3:23 pm It is a big issue, especially considering that many new subdivisions are usually Class P sites due to fill and reactive clay soils are quite common in Australia. I am lucky in that my land is Class S. My next door neighbour though has a class P due to low load in one of the bore holes, so a lot also depends on where the bore holes are drilled. Perhaps two drill holes, which is usually standard for site investigations, is not enough to get the full picture of the site. Then of course is the issue with slabs being under-engineered or the builder not completely following the engineer's recommendations. I work for Local Government in QLD and the Council Building Certifiers are talking that there could be a change in legislation which enables owner's to choose their own building certifier - certainly would help the "i scratch your back, you scratch mine" between some builders and certifiers. Perhaps that is the best way to solve the issue - more drill holes in site investigations and giving owners the flexibility to appoint their own certifier, removing the issue of builders using their own. But, that requires legislation change and does not help the existing or current issues... Dale - Building Newbie Proserpine, QLD Re: Are you building in a problem soil area? 3Oct 07, 2014 3:43 pm I agree dalemengel, Extra bore holes or mandatory map investigation or both. As to certifier, do you mean the building surveyor... because they have the power as last man standing in the documentation stage, of being able to override the design if they think that there is the need to take more precautions. For instance if the soil reporter recommendations were not made part of the design, or there is a large tree nearby or (shudder) a row of trees, then the building surveyor has a duty in a way of considering these issues, especially if the other documenters have not. Sometimes the poor builder, who can also insist that the design is not good enough can pull out, but that does not occur too often alas. In Victoria, we already "pick" (well usually the builder picks) the building surveyor, and sometimes these building surveyors are far removed from the area that the house is being built in, and have no local historical knowledge that a local council building surveyor has. This is often quite a mess, so let's hope that at least home owners become more aware Cheers Leonardo_23 Re: Are you building in a problem soil area? 4Oct 07, 2014 3:52 pm Yes, I mean the building surveyor/inspector. Up here they are usually called building certifiers, but the same job - to inspect the house during various stages to ensure compliance with the BCA, grant the decision notice (permit) to build etc etc. The builders can choose to use Council or a private certifier, so the builders have a choice. But I believe there is talk about giving more power to the owner - the owner chooses the building surveyor rather than the builder. Of course that wouldn't help in situations where the builder/developer buys the land, builds on it and then sells as a house and land package. Luckily I am in a small rural area, so don't usually have issues with local builders or surveyors as they simply can't afford any bad press as they rely solely on the area to generate income. Word travels very fast in a small area, so bad press has significant impacts. Different story with the larger, state/national builders but even then it comes down to the SS and the contractors/tradies. If you have good ones, usually no issue - but it can be a bit of a lottery as to which you will get! Dale - Building Newbie Proserpine, QLD Re: Are you building in a problem soil area? 5Oct 07, 2014 4:05 pm This subject has also been discussed extensively at the following thread: Protecting Your Slab viewtopic.php?f=31&t=70245 The Harder You Try - the Luckier You Get ! Web site http://www.anewhouse.com.au Informative, Amusing, and Opinionated Blog - Over 600 posts on all aspects of building a new house. Re: Are you building in a problem soil area? 6Oct 07, 2014 11:27 pm Thanks bashworth about the previous (and still current) thread... 'Protecting your slab'. I'll tune into that too. Did you see that there was a general meeting at St Kilda Town Hall yesterday. Pity I was committed to tennis. Did you happen to go ? That would be a terrific thread on its own also, don't you think? Let's get this enormous issue out there in people's faces. Good old homeone! I think there is a lot of room for a fresh approach, so let's see how this goes. I have quite a few ideas. So I think there is enough room for a similar thread on this topic, because it is perhaps the most important item for all home owners... the foundations of the house. Leonardo_23 Re: Are you building in a problem soil area? 7Oct 07, 2014 11:40 pm Hi everyone again, There is another important thread linked to this topic also which I should mention in line with bashworth's comment. There is another thread 'Pre-Slab Inspection started by Lilyana also worth a read, Cheers, Leonardo_23 Re: Are you building in a problem soil area? 8Oct 08, 2014 6:47 am I'm in Melton & in a highly reactive clay area, we had 5 bore holes & are getting a waffle slab.. Within our contract it has recommendations on how to avoid slab heave but yea they're only recommendations.. In order to get our structural guarantee we have to follow them though, so our landscaping will revolve around those recommendations.. Home Solution by Metricon - Luna 28 http://hayleyandjonshouse.blogspot.com.au/ viewtopic.php?f=31&t=73643 Re: Are you building in a problem soil area? 9Oct 08, 2014 11:11 am Leonardo_23 As I see it, the main problem is keeping the public aware of the possible problems and the end of their reliance on people who are not caring enough. that is it in a nutshell. The building industry "chain" has too many deficient links in it to provide complete consumer protection. This forum alleviates the problem soemwhat for those who take the time to learn from it. Leonardo_23 Were the recommendations in the soil reports for instance followed to a tee. Any why are they only recommendations and not requirements. Perhaps a bit of extra legislation is needed to make certain that soil reports are followed right down to their last recommendation. I dont think so. Soil reports , in Qld anyway, have a component where instructions are given to the owner about foundation maintenance if they build. Contingent engineering reports are based on this being followed as well. If the owner does not uphold those maintenance directions, then he/she is liable in any attributable failures resulting from that. We have seen this ruling in court cases. Leonardo_23 Anyway I'm just offering this as a start to what might become a huge awareness campaign in problem soil areas. Leonardo_23 Most Facets of this have been discussed extensively her already. Re: Are you building in a problem soil area? 10Oct 08, 2014 12:53 pm I agree quebtel, But you raised an interesting issue about footing maintenance and the onus being on owners to uphold them... same as in Victoria... where there is a sort of a buck-passing (cop-out in my opinion) against owners... and fair enough if they plant fast growing trees near their house... But until recently the CSIRO 10-91 pamphlet referred to in Vic soil reports actually told you about rows of trees and groups of trees and appropriate distances for these from houses. Now though the public have been dumbed down and the immediate CSIRO replacement BTF documents had no such information. I think this was because of existing trees on neighbouring properties and the onus then falling squarely on the shoulders of soil reporters, structural engineers, building surveyors and builders to take appropriate measures. There were also very few soil reports that contained these referred-to maintenance of footings guidelines. Courts can be unfair places, so it pays to have the best experts or you are going to lose most times, Cheers Leonardo_23 Re: Are you building in a problem soil area? 11Oct 08, 2014 12:56 pm Hi heychhhh, Sounds as though your builder is taking the reins of responsible advice... full marks! I've heard a few others are insisting on perimeter apron measures also. I wonder if they all place underlay under the concrete aprons though, because concrete is porous and not a good idea otherwise in long-term droughts for instance, Cheers Leonardo_23 Re: Are you building in a problem soil area? 12Oct 08, 2014 5:40 pm Also talked about on this thread Has anyone rectified slab heave successfully viewtopic.php?f=1&t=64836 Re: Are you building in a problem soil area? 13Oct 09, 2014 12:25 pm I was at the meeting Tuesday night. It was great to speak to others in the same position. Although our stories are all terrible there is strength in numbers. Please support the building compliance reform association, they work they are doing has the potential to bring about major changes to the current system of (zero) building control. Their website is http://www.bcra.asn.au They also have a Facebook page. Re: Are you building in a problem soil area? 14Oct 10, 2014 12:28 am Thanks Insider, I'll take a long look at that thread too... looks impressive number of posts. The thing about heave is that the building code states that heave must be considered but it rarely is in my experience... hopefully changing for the better soon. Personally I don't like highly reactive clay soils and suggest suspending the slabs so that heave cannot be a problem. Leonardo_23 Re: Are you building in a problem soil area? 15Oct 10, 2014 12:34 am Hi Velcro, How many showed up/ Did the ministers all agree or was there large disagreement that there had been failure in the system? I listened to Jon Faine one morning on ABC and he was going on about the fact that the largest cost facing new families was the cost of litigation in VCAT; but when he asked the HIA, Consumer Affairs and a few others he invited to the meeting they all disagreed vehemently about the figures and statistics was all that seemed to happen. One thing is for certain... there is a lot of trauma out there as regards poor building,.. hope the association gets somewhere... I might join to find out what's going on. Cheers Leonardo_23 Re: Are you building in a problem soil area? 16Oct 10, 2014 1:47 am With a statistic being shared at the meeting in st kilda by the bcra it revealed in 2011 alone around $88 mil was received in home warranty insurance premiums - yet only 3 separate claims were successful of claiming. Those 3 cases combined only came to $108,000 - what happens to all the rest? Meanwhile while the victims to this building fiasco continues to increase - NONE of those reaping the benefits of the building industry seem to be in a hurry to want to change it. Re: Are you building in a problem soil area? 17Oct 10, 2014 5:42 am Leonardo_23 Thanks Insider, I'll take a long look at that thread too... looks impressive number of posts. The thing about heave is that the building code states that heave must be considered but it rarely is in my experience... hopefully changing for the better soon. Personally I don't like highly reactive clay soils and suggest suspending the slabs so that heave cannot be a problem. Leonardo_23 Yes I agree and using something most builders wouldn't have heard of before and that is void formers but still there are bigger issues that need to be addressed as well. Re: Are you building in a problem soil area? 18Oct 10, 2014 10:10 am The thing about heave is that the building code states that heave must be considered but it rarely is in my experience... hopefully changing for the better soon. Personally I don't like highly reactive clay soils and suggest suspending the slabs so that heave cannot be a problem. Leonardo_23[/quote] Just to jump in on this thread. We are building on H1 class soil and, as owner builders, slab heave is exactly the type of thing we are hoping to avoid. We have gone for an Ultrafloor suspended slab. Costly but hoping the extra $$$ helps save problems down the track. Re: Are you building in a problem soil area? 19Oct 10, 2014 11:16 am I also attended the BCRA public meeting on Tuesday night. While not affected by the poor regulatory system in Victoria, I felt that it was important to show support for those that are. Senator John Madigan spoke with passion about his own apprenticeship and showed empathy and a depth of understanding of the situation. Conspicuous by their absence were the 10 other invited political and regulatory figures who's photos (mug shots) nevertheless adorned 10 seats that faced the audience. For several of the 10, the Victorian situation has occurred on their watch . Highly reactive soils and slab heave were not the main subjects, there are many areas of the industry where people have been let down. V-CAT has gone off the rails. To hear of people spending $200k - $300k and then having to abandon their case when they have run out of money was gut wrenching. Wasn't V-CAT set up to take pressure off the courts and serve as a low cost alternative and why are people forced to spend large amounts of money when a proper regulatory system should be protecting them? The building industry has many well organised and funded associations to protect their interests but new home owners have none. The BCRA needs support but public meetings like the one on Tuesday night should draw the support and expertise they need. The new Victorian Building Authority (VBA) was set up without the regulatory power that is needed. Why? http://www.theage.com.au/victoria/the-n ... 3al87.html The BCRA is a small group taking on a big job and it is important that the group grows in strength. It must be remembered that the founders are people who have being badly let down by the lack of consumer protection in the housing industry yet they have taken on this demanding task to try to help others with public education to help bring about needed reform. I would rather find myself next to those people in the trenches than the ones in the mug shots who seem to have deserted the cause. http://www.bcra.asn.au/ 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: Are you building in a problem soil area? 20Oct 10, 2014 12:04 pm SaveH2O V-CAT has gone off the rails. To hear of people spending $200k - $300k and then having to abandon their case when they have run out of money was gut wrenching. Wasn't V-CAT set up to take pressure off the courts and serve as a low cost alternative and why are people forced to spend large amounts of money when a proper regulatory system should be protecting them? Civil Courts dont do anyone favours, they are still the same fee charging arm of the state's judiciary if you want to use them, but the bulk of those fees would be solicitors fees. At the end of the day, trouble is to be avoided at all costs, and solicitors are to be avoided at all costs (for anything complex and protracted). CDC Housing Code 3 When to apply Floor Area external face of wall vs Gross Floor Area internal face of wall. Reading thru CDC Housing Code 3, lets take a lot 915sqm.… 0 16559 With that sort of soil type if you ask for a design to include piers then I would also include void formers. That way you should reduce the chances of settlement and heave. 7 4633 Even if it's not being sub-divided and you want to keep it as Torrens title, you will still need to talk to a town planner or Council themselves, to see if they will allow… 1 11035 |