Browse Forums General Discussion Re: Some Slab Protection Questions Please 4Sep 08, 2020 11:27 am Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Some Slab Protection Questions Please 9Sep 08, 2020 11:47 pm Lisa06 alexp79 You would use non porous fill such as compacted clay when grading away (i.e. clay lock). A good design will be to also install a layer of builder's film under the clay lock. And another important aspect is to decide where do you grade away to. Ideally, it should be grading away to a drainage. Hi Alex, Thanks for that info. Yes, I agree with the drainage. Is builder's film some sort of plastic? Yes, it is a film made of waterproof plastic, sometimes can be also referred as geomembrane. Re: Some Slab Protection Questions Please 10Sep 09, 2020 7:32 pm Harts Hi Lisa06 Australian Standands 2870-2011 5.6.3 Drainage Requirements – Buildings on moderately, highly or extremely reactive sites shall be provided with drainage systems designed in accordance with the following: (a) surface drainage shall be considered in the design of the footing system & necessary modifications shall be included in the design documentation. Surface drainage of the site should be controlled from the start of site preparation & construction. The drainage system shall be completed by the finish of construction of the building. AS2870-2011 5.2 Drainage design requirements - “Surface drainage shall be designed & constructed to avoid water ponding against or near the footing. The ground in the immediate vicinity of the perimeter footing shall be graded to a fall of 50mm minimum away from the footing over a distance of 1m & shaped to prevent ponding of water. Where filling is placed adjacent to the building, the filling shall be compacted & graded to ensure drainage of water away from the building. Hope this helps Thank you -it does. Re: Some Slab Protection Questions Please 11Sep 09, 2020 7:37 pm alexp79 Lisa06 alexp79 You would use non porous fill such as compacted clay when grading away (i.e. clay lock). A good design will be to also install a layer of builder's film under the clay lock. And another important aspect is to decide where do you grade away to. Ideally, it should be grading away to a drainage. Hi Alex, Thanks for that info. Yes, I agree with the drainage. Is builder's film some sort of plastic? Yes, it is a film made of waterproof plastic, sometimes can be also referred as geomembrane. Thanks for that. Is there anyway we can find out if the builder graded the land away from the slab correctly during construction? ie. right angle and fill-type etc? The land is certainly not graded away from our slab correctly but the builder will likely blame the first owner. Re: Some Slab Protection Questions Please 12Sep 09, 2020 8:10 pm Lisa06 Thanks for that. Is there anyway we can find out if the builder graded the land away from the slab correctly during construction? ie. right angle and fill-type etc? The land is certainly not graded away from our slab correctly but the builder will likely blame the first owner. "... fall of 50mm minimum away from the footing over a distance of 1m " clay should be well compacted (meaning it looks like it is being smoothed with something and tough when you press it) Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Re: Some Slab Protection Questions Please 13Sep 09, 2020 8:21 pm Lisa06 Hi Chris, Does any sort of guideline state that temporary downpipes are required on reactive soils? Our engineer plans don't mention temporary downpipes. Given that we are in lockdown for likely the rest of 2020, I don't think any students are going to be able to assist. Thanks. EDIT: Our engineer plans actually DO state that temporary downpipes must be used during construction!!! Interesting. So you can see how easy it is to miss critical information... guys on site overlook that information all the time.. It's not a hanging offence The saving grace is that others check the works as it proceeds and FUs gets rectified. Unless the engineer pointed out the consequences directly to the builder and he then ignored the details/instructions. Then the case of the Builder Failing in his "duty of care" is difficult, onerous and legally expensive to prosecute. OT, Student research programs requires Supervisory Guidance by a professor, Access to test facilities and the use of expensive software. Most private engineering practices don't offer that service for housing. Cheers Chris Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Some Slab Protection Questions Please 14Sep 10, 2020 10:57 am alexp79 Lisa06 Thanks for that. Is there anyway we can find out if the builder graded the land away from the slab correctly during construction? ie. right angle and fill-type etc? The land is certainly not graded away from our slab correctly but the builder will likely blame the first owner. "... fall of 50mm minimum away from the footing over a distance of 1m " clay should be well compacted (meaning it looks like it is being smoothed with something and tough when you press it) Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Ours looks nothing like that. There is just soil around the house and it looks like it's at a very slight slope. But it is certainly not compacted at all. Re: Some Slab Protection Questions Please 15Sep 12, 2020 6:38 am Just a point on those temporary light weight plastic downpipe hoses. In our case the builder installed them as soon as the guttering went up, but they were totally useless. Our block is exposed and when it rains it is usually also windy so the plastics just disconnected from the drainage points and were of no benefit. They were always just flapping in the breeze until proper downpipes could be attached. It was also impossible to grade away from the slab on one side because we are built to the boundary there. I now note (after handover) as we are about to start the landscaping, the yard gully points are also full of dirt from from having loose soil all around during the build, perhaps these should have been capped off after rough in as well. Yes, neither is termite damage that is not covered by your house insurance. 3 6590 Hi VK, Think it's worth investing time in an Owner Builder course to equip you with basic knowledge on Australian Building Industry and its regulations. Also, I suggest… 11 23285 |