Our first tender included $7500 for screw piles under Foundation Modifications. We complained this was way over their initial site cost estimate, and the builder came back with a revised tender which included $2500 for bulk concrete (instead of the $7500 screw piles).
We just received our contract, and in that, the $2500 has been increased to $7000 "due to angle of repose, rigid slab, modified waffle pod slab and structural computation design"
Questions ...
1. screw piles vs bulk concrete - which one is better in terms of performance?
2. if the builder refuse to reduce this charge, should we ask them to go back to screw piles, as the price diffrence is now only $500?
3. what is angle of repose?
4. can they have a rigid slab and a modified waffle pod slab in the same house?
5. is the above explanation justify tripling of the bulk concrete cost?
Ours is S class slab on P class site (sandy soil, with engineered fill of 500-1000mm)
Any advice would be apperciated.