Browse Forums General Discussion 1 Jun 18, 2013 2:16 pm We're in the blue mountains and a lot of the blocks we're looking at are either partly solid rock or have lots of boulders. The soil itself is very sandy. The house we're renting is built directly on the rock so I'm guessing it can be done somehow! We are going to have a steel flooring system like spantec rather than a slab and I'm wondering if anyone has done this on rock and whether the presence of the rock incurred additional costs. I have emailed a flooring system company about it but they won't give any indication without looking, and we haven't bought a block yet. We're just needing an idea of whether this will cause a huge issue or not. Re: Building on rock 2Jun 18, 2013 5:04 pm You will have to establish if the rock is a shelf or floaters and this is usually done by test drilling. The problem is that you should have a pretty good idea of the house plan and it's location on the site because the drill holes need to be done at the actual footing locations otherwise you are wasting your money. The test drilling company will then recommend the type of footing best for the site. The whole point of this is to get the whole house onto the same foundation material so it doesn't have differential settlement. If half of your house sits on rock and the other is on say sand you will get a lot of cracking. There are ways to overcome different soil types such as bridging and piers but all this adds cost. So in answer to your main question: yes it will cost money in design and execution. But don't be deterred if it's a dream site get an engineer who is familiar with the area to advise you before you buy. Hi all, I have been looking at land in South Australia, that is on a slope however most of the core excavation is complete, with a flat area to place a house. The agent… 0 1379 Thanks for your reply. I will just wait and see I guess. Trying to get some more information from our builder. 9 29919 |