While a lot of Cantabrian lifestylers are lucky to be blessed with flat land for their block, if you live out toward Akaroa, Sheffield or closer to the hills then there's a chance where you want to build your house, or shed,isn't perfectly flat.
Building Into the Slope
For gently sloping sites, the most cost-effective approach is often to cut into the hillside to create a level building platform. This allows for a concrete slab foundation, but depending on the steepness, you may also need a retaining wall to support the higher ground. A qualified engineer must design this wall, and it will need to be included in your building consent and inspected by the council. We can handle all of this.
One thing to factor in is what happens to the soil that’s removed. Small amounts can usually be kept on-site, but if major excavation is required, you may need resource consent to truck the spoil off-site, which can add significant costs.
Building Out of the Slope
On steeper sites, it can be more practical and cost-effective to build out from the slope using a timber pile or pole foundation instead of cutting into the hillside. This method disturbs less soil and avoids major excavation work.
With this approach, the timber floor is supported by piles or poles that are specifically engineered to suit the soil conditions. The poles can either be:
✅ Driven (rammed) into the ground – No spoil removal required.
✅ Set into drilled holes and surrounded by concrete – More stable in certain conditions.
The choice depends on soil structure and site accessibility, and your engineer will help determine the best option. In some cases, cross-bracing may be needed between the poles to add stability.
A Combination Approach
Some builds use a mix of both methods. For example, you might excavate a level platform for a concrete garage floor while the rest of the home is built on timber piles. This can be a great way to maximize cost-efficiency while working with the natural slope.
Plan Early for a Smoother Build
Sloping sites come with unique challenges, but with the right approach, they can result in stunning, elevated homes with great views. The key is early planning—consult with an experienced builder and engineer as soon as possible to explore the best foundation options for your site.