Site survey and soil test
A Geo-technical engineer will conduct the testing and will deliver a report on your block of land. The site survey records key features on both your block and the area neighbouring your lot. The soil test will determine your slab classification, as well as indicate if any rock removal is expected.
Your new home needs to be built on level ground. The land is levelled by a combination of cutting soil away from the higher end of the block and/or adding new fill to the lower areas. The fill must be compacted properly to ensure your land is stable. If this can’t be achieved satisfactorily, concrete piers will be put in place to make it stronger. Where required by the council, crossover protection may also be used. If there are rocks underneath the surface, these will be removed and taken away where appropriate.
These are used to retain the earth on your land if required. In the case where a block of land is too close to a boundary and we can’t fully cut or fill it, we will need to build a retaining wall that holds the soil and ensures a flat building platform can be achieved.
Where soil conditions are not stable to a satisfactory level, or if your house is in close proximity to mature trees or easements, an engineer may specify the use of concrete piers in the ground to support the house foundations. To do this, holes are dug until they reach solid foundations and concrete is poured into them to achieve stability.
The engineering company determines your slab classification in accordance with the soil report. In some instances there may be a need to increase the stiffness of the slab, which can be achieved by increasing the steel mesh size, and the amount of concrete used.