Browse Forums General Discussion Re: H Slab - Screw Piles 4Oct 05, 2006 9:41 am Peter Clarkson - AusDesign Australia www.ausdesign.com.au This information is intended to provide general information only. It does not purport to be a comprehensive advice. Re: H Slab - Screw Piles 10Oct 06, 2006 4:22 pm I feel for you all & I'm not sure how to put this without sounding insensitive so I'll just say it & cop the flack.
One of the golden rules of land purchase is to buy subject to a satisfactory soil test (geotechnical report) . . . . now i'll duck for cover. Peter Clarkson - AusDesign Australia www.ausdesign.com.au This information is intended to provide general information only. It does not purport to be a comprehensive advice. Re: H Slab - Screw Piles 12Oct 06, 2006 7:02 pm Some builders are pleased if the soil test result is "P". It creates a variancy clause which they can exploit. Ask for a breakdown of costs of the footing snd slab design. Also why the preference for screw piers? in shallow fill bored piers are way cheaper. Also installation depth should be through fill and into natural ground to achieve torque equivallent to 5 - 10 tonnes capacity. They also are designed only for compression (in the residential slab) so reactive soiol movements require additional slab design considerations. Re: H Slab - Screw Piles 13Oct 07, 2006 10:13 am Pardon my lack of knowledge here, but wouldnt it be cheaper to use stumps or sub floor rather than all these expensive fills, compaction and screw piles? I realise that this has other implications such as energy rating and height of the building etc. However, many builders do not even want to consider building with stumps or sub floor. Why? I did ask them but the answer is always: Oh! but we don't do that. Re: H Slab - Screw Piles 14Oct 13, 2006 5:42 pm Timber floor construction has become more expensive than a concrete slab on the ground, or at least that is what most project builders will tell you. Most building companies are simply not geared up for it. So they don't offer it as an option. Yet timber floor tiles over a concrete floor is becoming very popular. The public wants what the public gets? I thought the public gets what the public wants. Re: H Slab - Screw Piles 15Jan 20, 2011 11:56 pm get afew opinions is my advise....we got told the same thing and would have been up for 20 grand on top of slab costs....we got afew more people out and both said we didnt need the screw piles...through my investigations....screw piles are needed on very sloppy blocks with alot of moisture and they will give more stability in the soil...so if your block isnt like this then do some research or get another opinion...its alot of money!!!!! Re: H Slab - Screw Piles 17Feb 06, 2019 11:02 am Sort off stumbled across this forum so will attempt to assist. The depth of pile should be according to AS2870 table 2.5. This table relates suction change (Hs) with climatic zone. In Mel the climatic zone is either 2 or 3 with screw pile depth min 2.3m or 2.9m. The requirement for screw piles is to go 1.25Hs As2870 G6.3) to get below the zone where movement can occur, however this requirement does not exist for concrete bored piers - something I hope will be consistent in the future. A good screw piling company will comply with the code. Screw pile price has come down quite a bit in the past few years and when you consider the uncertainty of final cost of concrete piers and potential weather delays. From my understanding, the industry was rattled a few years ago with waffle slabs and homes cracking - this may be a reason for a more conservative approach to classifying sites. There are good options for reactive sites, one of which is a suspended ground floor slab www.polyvoid.com.au which has a track record of minimal cracking from reactive soils and compares very well cost wise. I must declare that I work for www.katanafoundations.com.au and www.polyvoid.com.au - however I am a Professional Engineer so my first obligation is to the broader community to assist where I can. Mark Armstrong BSc (Eng) MIEAust CPEng Development Manager http://www.katanafoundations.com.au http://www.polyvoid.com.au http://www.biax.com.au Re: H Slab - Screw Piles 18Feb 06, 2019 3:20 pm Welcome to the forum Mark and it is proper that you have upfront declared interest in the companies where you work. That is a decent approach and I for one would have confidence in listening to what you have to say. Foremost Building Expert in Australia,assisting with building problems/disputes, building stage inspections,pre-contract review advice for peace of mind 200 blogs http://www.buildingexpert.net.au/blog Re: H Slab - Screw Piles 19Feb 06, 2019 3:38 pm building-expert Welcome to the forum Mark and it is proper that you have upfront declared interest in the companies where you work. That is a decent approach and I for one would have confidence in listening to what you have to say. Thanks - day one and I got a call and assisted where I could. My interest is really in assisting folk with getting the foundations right. Everyone spends lots of time looking at taps and tiles only to live in a home with cracks in it - that's not right. If it is a while after the build - like a wet spell after many dry years - it goes to the insurer and we never get to hear about it. That means little feedback to the code committees like AS2870. Look forward to productive discussions. Mark Armstrong BSc (Eng) MIEAust CPEng Development Manager http://www.katanafoundations.com.au http://www.polyvoid.com.au http://www.biax.com.au Re: H Slab - Screw Piles 20Feb 08, 2019 3:27 pm Engineer building-expert Welcome to the forum Mark and it is proper that you have upfront declared interest in the companies where you work. That is a decent approach and I for one would have confidence in listening to what you have to say. Thanks - day one and I got a call and assisted where I could. My interest is really in assisting folk with getting the foundations right. Everyone spends lots of time looking at taps and tiles only to live in a home with cracks in it - that's not right. If it is a while after the build - like a wet spell after many dry years - it goes to the insurer and we never get to hear about it. That means little feedback to the code committees like AS2870. Look forward to productive discussions. brilliant and simple concept,start looking at what is between and under your walls and structures,this is what is to me the MOST IMPORTANT PART OF NEW BUILDS,stone etc is a luxury that you put in well after structure, trouble is emotion of what people see rules their heart,but poor structure can ruin lives,well said Mark. If what you describe is correct then the brick wall has been dry lined with villa board. That basically means that the villa board is glued to the brick wall with… 3 6084 Hi all, Trying to workout the minimum stepdown required between slab for my house and the outdoor alfresco area. Garage is 100mm lower than rest of the house and plan was… 0 3649 Thanks for the insights, that makes perfect sense, and yeah, I will be leaning on the experience of the excavator operator entirely. 6 11035 |