Honestly it sounds like too much on top for a M waffle slab? N3 rating only adds $2500. Can someone please help? Does this price sound right? Should we be paying council fee etc? I thought that would be in contract?
As a guide our slabs with concrete piers cost us around $250/sqm, screw piles are a lot cheaper at around $70/ lineal meter, so assuming each pile is 3m piling would be circa $6000 plus GST and builders margin.so a 200 sqm slab would cost us around $40-50k. Not sure if this info will help
The N3 rating mainly relates to the bracing and tie downs of your frame to your slab. I would be happy to send you the relevant tables from AS1684 if you like so you can see what is needed.
Its hard to tell if you are being overcharged or not without knowing what they had allowed for in the original quote for the slab.
I know they didn't allow for screw piles which we need 28. The contract has allowed for a "base" being $39,343.50. The 15k extra was to cover us if we needed a h1etc. Would I as a lay person be able to understand the table?
honestly no you wouldnt and even as a builder its a crock of s*%t. Project home builders are the only ones who do this soil classification as a way of extracting more money from poor consumers,
Qualiity builders pier as standard as we know we are liable for the structure for 6 years. I only know about soil classification as I worked in the project home sector for a time, but for the other 20 years of my career I have never come across another builder who would even know what this means!
Basically they are saying you have P for problem soil meaning that it has most likely been filled and you need to pier to rock, which should be standard for all builds anyway.. Personally I am not a fan of screw piles. They are ok but we have had some homes sink in P soil back in my project home days