Load-bearing capacity of L-stone and water drainage at 45° slope

It doesn't really sit on a throne; on the right, we let it taper off into the neighbor's slope, on the left the neighbor sits a bit higher, so that the whole thing should appear harmoniously sloping again. Down below there is plenty of space to the houses, which are so tall that we ourselves can only see over them from about 305m upwards. And behind us, there are again such tall houses that the tip of our roof just reaches their ground floor. Our predefined single-family house is simply not up for discussion... But I wouldn't want to steer the thread in the wrong direction now.

Even though we will not have children, we have, of course, thought about the 2m wall; the first thought was to put a fence on top of the wall and the second thought was somehow to try to plant something that requires little or no maintenance. Hence the idea of additional bushes that should prevent a fall. I have to admit that I have absolutely no knowledge of plants; currently, I only look down on many flat roofs, all of which are greened, and I thought to myself that these plants have probably never been cared for and still look nice, so they should certainly be able to thrive on such a slope as well.

It sounds almost unsolvable here, which is why it seems we should actually already hand over the money for the garden landscaper before the wall comes. Just wanted to hear your opinion (also regarding the statics of the wall). I had hoped it wouldn't be so hard to find plants for this and thought to lay some sort of trough made of some gravel along the wall at the bottom (i.e., at the top edge of the L-stones) and then a kind of soakaway at the lowest point where it can collect. But the flow velocity down the slope does not change because of this, of course, and at first probably shoots over the wall...

You just have to take a look at the noise protection walls along highways or dikes as a comparison; they usually should not have a 45° slope. Despite construction by specialist companies and professional planning, something regularly slips there. The difference is that it can't fall on your head as a 2m high wall, but only on the shoulder. I believe that this specific problem is not for forum collective intelligence, but for an expert.

At a 45-degree angle, you need to create a base for plants in which both substrate and roots can find support. And they must take root very quickly and deeply. Then, on the south side, where the sun burns everything away. There isn't much that can manage that, and it will be very labor-intensive. You don't want to plant a blackberry hedge. Or just ivy. The slope needs a substructure, like a dike or a noise barrier on the highway, plus the pressure from the building. The earthworks contractor should make a clean plan for this with a cost estimate, and with that, I would go to a landscaper who is experienced with hillside construction.

Do you have crampons? You need them if you want to maintain a 45 degree slope above a 2m ledge. Bare earth is bad to step on there and grass is even worse, but crampons hold very well. The construction is a nightmare to maintain

The thing with the planning and the earthworks is a bit tricky; we had five on the property now, three of them were the three biggest in the region, or rather within the operational radius of our property. I drew a model for illustration using a CAD program for mechanical engineering, which doesn’t really have much to do with architectural drawings (in other words, it just looks ugly and technical). Unfortunately, the gentlemen were very enthusiastic about it and made it clear to me straight away that they don’t have anything that cool :eek:.

I’m going to find a landscape gardener who can plan and see what comes of it.

I wouldn’t have thought that the plants would be such a problem, let alone that they require maintenance. What kind of plants are those on the flat roofs? They are rather very flat and wide (so little surface area), only get rainwater, grill in the sun all day, and receive no love at all…
I thought the statics of the wall and the water were my main problems :rolleyes:…

As so often before, building a house is a total surprise box…

Thanks for your honest answers, still learned something here again!

Flat roofs are not slides. Your 45-degree slope is. You would also need to provide irrigation for the entire slope area so that the plants grow well enough to hold the slope. A heavy rain on dry soil and your slope ends up in the neighbor's yard. The same can also happen if too much is watered. In the neighboring town, a street was closed a few years ago because a defective irrigation system led to a “landslide.” (Although we wondered why the owner didn’t notice that several cubic meters of water were pumped into the ground more than planned.) Long story short: question the statement of the earthworks contractor that this is not a problem. That can simply mean building is no problem, afterwards it's none of their concern. As my father would say, I can also build you a hammer out of chocolate. You will be able to build the slope in that shape, but you should know the effort involved.