Site planning on a gentle slope with filling

Maybe we should really consider reducing the planned 20cm above street level, good point.

Then terraced descending as described (but maybe with a 2*80cm offset).
I had calculated with 400m³ of lava, with compaction that should be about 700 tons, which are accounted for.


The neighbors have the worst of both worlds: basement, surrounded by fill and still anchored beside/behind the house, which we wanted to avoid :D With a basement without fill, the house would either look like a tower or sit below street level, which was too risky for us after the flood disaster in 2021. But basement was dropped anyway due to the requirement "age-appropriate living on one level must be possible." We had other priorities in the floor plan; the question of the design of the rest of the property was then secondary, until now.

The house and the garage 30 cm lower. Then in my opinion, you still have a 3% slope to the street.

That is then 0.3 * 20 * 30 = 180 m3 less fill.

How much does it cost you to deliver and install 1 m3 of load-bearing fill material?

There are many hillside houses, and if properly planned, it should be no problem during heavy rain. Of course, barrier-free access is somewhat in conflict with having 2 levels. But a hillside garden is like that too. With terraces and stairs, somewhat less so; with a 45-degree slope, quite a lot.

For the driveway, I would consider whether the lowest point could be in the middle and then the water diverted past the house with a cross slope.

Top edge of finished floor on the ground floor is applied for at 479.00m, street level is on one side 478.93m (water flows down from a cross street there when it rains) and on the other side 478.60m. To go to 478.70m, a slope from the house to the side would have to be created.


Completely agree. The garden would then only be viewable from the upper terrace at the house in old age, if climbing stairs eventually becomes impossible. But we probably won’t get around that.
The driveway with a gutter is a good idea, it could also divert the water from the cross street in case of a lower house position.

I will probably draw this a bit cleaner again tonight and think about it, thanks for your input.

I didn’t mean just a gutter, which quickly gets overloaded or clogged with dirt during heavy rain. I meant a proper cross slope. Our house is also below street level and neighboring properties that are higher. The plan is to really divert water around the house if necessary. A gutter will still be placed in front of the door as a precaution, but actually, everything is planned so that it would work without the gutter.

If you construct the garage driveway with the slope of the terrain (5.5%), you can build the house and the garage about 75 cm lower. This makes the outdoor area significantly easier. Please remember to roughly prepare the outdoor area beforehand. Because you can no longer get past the house with an excavator.

Why did you black out the heights at the boundary?