Driveway planning for large sloped property - 25% gradient

Does your driveway go up to the house? How long has it become and how extreme is the maximum slope? Would you build it the same way again?

The driveway reaches up to house level, which is 10.5m above the street. I don’t know the exact length at the moment; it’s between 80 and 110m depending on where you measure up to. The slope is not linear, the steepest part is right at the beginning of the driveway but probably doesn’t exceed 20%. I haven’t measured it. Initially, we planned to keep the whole thing less steep and shape the last section with stairs to the house. I am really glad that we had so much excavation to build up a bit on the eastern hillside and then manage to climb higher with a somewhat larger curve. Currently, the driveway is gravelled, which does not work well in the two steep spots. Guests and delivery services are unable to drive up without spinning tires. So next year we will tackle it again and think about what to do. We don’t want to fully pave the whole area.

With appropriate earthworks it will work, but as already mentioned, that will cost.

That should not be underestimated, but also not calculated in isolation, because if you already have excavation from the house and can use it, you have positive effects on another budget side like transport and disposal. Besides the earthworks, the hillside supports are not trivial either – no matter what you use: it always costs a lot.

Is outside the building permit area.

You just have to ask whether you get approval. Sometimes you wonder what is allowed and what is not again.

How about a straight driveway with a turning area (red), carport (black), and a staircase (blue) to the house?
The turning area, of course, executed at grade...

€: You could basically dig the road into the slope. Support it uphill side with a concrete wall or L-bricks, on the slope side do a little sloping. The resulting triangle could then be planted.

€2: You could then plant a hedge on the L-bricks as a privacy screen to the garden.

The idea is quite similar to my last sketch:


Only that, of course, mine still has a curve and the garage is turned into the building area. Could really also be a good idea.
The straight down part is also no problem. You rarely drive the road north. There is a path going down, but I think it is not open for regular traffic.

The driveway goes all the way up to house level, which is 10.5m above the street. I don’t know the exact length at the moment, it’s between 80 and 110m depending on where you measure to. The slope is not linear, the steepest part is right at the beginning of the driveway, but it should be no more than 20%. I haven’t measured it.
At first, we planned to keep the whole thing less steep and design the last part with stairs up to the house. I’m really glad that we had so much excavation material to build up a bit on the slope side in the east and then still get higher with a somewhat larger curve. Currently, the driveway is gravel, which doesn’t work well on the two steep spots. Guests and delivery services are not able to get up without spinning tires. So we will revisit it next year and figure something out. We don’t want to seal the whole area completely.

You shouldn’t underestimate that, but also don’t calculate it in isolation, because if you have excavation material from the house anyway and can use it, you have positive effects in another budget area like transport and disposal. Besides the earthworks, slope supports are not without cost either – whatever you take: it always costs a lot.

That’s quite a stretch you have there. You can compensate a good height difference over that distance.

Were you allowed to just use the excavation material like that? I’ve also heard that not every soil quality can be used for building up (e.g. under the driveway). Sure, in a normal, undeveloped garden that’s probably no problem, but if we need something under the house or under the driveway, to my knowledge it has to be a certain quality, right?

Slope stabilization and soil report will also be an exciting matter. We want to do that only once it’s clear how the driveway will actually be realized.
The neighbor on the undeveloped side also has substantial “embankments” (which are almost vertical) and go down about 3 meters. They are heavily overgrown (small trees and shrubs). Therefore, I’m hopeful that the soil is quite good in terms of stability (if you can call it that).
According to the first statement by the geologists, it is probably sandstone there, overlaid by mixed-grain slope sediments… hope that’s good?

Depending on the place of residence in Lower Franconia, winter services should not be neglected. On the Main, it's not much of an issue, but in the Rhön and Spessart, it should be taken into account.

try using grass pavers in that area or just paving the driving lane, as is often seen on field paths

try paving with grass pavers in that area or just the driving track, as is often seen on field paths

I have also thought about the driving tracks, we’ll just take a bit more time until we have the right idea. It works fine as it is.

: We moved and used the stones and soil on the property and no one thought to ask "may I do that." In relation to the size of the property, the excavation was not that noticeable. It looks as if it had always been that way.

Sorry, I misinterpreted the slope. Of course, that won’t work with my picture... My dentist, who has since become a good friend, built the house before ours in terms of time. He recommended the architect to us... With his house, however, the slope is exactly reversed compared to ours, so like yours . I can't provide any pictures, but I'll briefly explain it in text.

The street is located to the east. The driveway leads over the southernmost part of the property (flat) to about the middle. The driveway is about 3m wide. The lowest floor (basement) is set back about 6m compared to the ground floor above. You can park under the ground floor over almost the entire width of the house (about 4 cars). Additionally, two more cars can stand in front on the driveway before the house. The basement contains an entrance area (cloakroom) and access to the cellar room. There is also a freight elevator. The ground floor has the "official" entrance, three children's rooms, bedroom, bathrooms, utility room. On the upper floor is the open-plan room (kitchen, living, dining room) as well as a WC and a pantry. The freight elevator has three stops. In the basement cellar room, in the utility room on the ground floor (for grilling in the garden), and in the pantry on the upper floor.

I hope I was able to convey it reasonably well and that you can get an idea of it.