Floor plan, house layout EFW 150m2, basement + granny flat - feedback desired

What conditions would have to be in place for the granny flat to remain in the basement?

A slope in the building window of about 2-3m, so that the basement becomes an underground floor with garden access without excavation. But you don't have that. So I wouldn't build it either. Half-heartedly planned buildings are usually rubbish and later repurposed because nobody needs them. So I certainly wouldn't voluntarily lock myself in that basement hole. My consideration here would be a small annex as a granny flat, probably in the northwest, to keep the access simple and level. Behind it, the house possibly on split-level height for an optical and perceived separation - all without a basement. However, it is difficult to assess whether the property is sufficient for that. I see no dimensions except the meager 650 sqm from #1. I understand that you want more garden and therefore prefer to plan the basement. But in the end, you have neither the garden, as it is eaten up by excavations, retaining walls, and railings, nor do you have a proper apartment where people like to live, because nobody really wants to live in a basement. So be careful with bad compromises, because in the end, you have only spent money and actually have nothing.

Hello Hanse987,
Thank you for your opinion. What would work for you? Does the apartment have to be out of the basement? Would it help to raise the basement? What about the design doesn't work? From pure rejection, I can hardly get any input that would help us improve the overall situation.
Do you have a granny flat or have you yourself ever lived in a basement and speak from experience?

I think this is quite easy to answer. As long as you like living together with someone in the same house, each party should be equally happy about the newly created living space. Just ask yourself whether you would move into this basement room with your family and accept the same arguments—surely you wouldn’t!
I myself lived this way for over 20 years and my parents first finished their apartment on the upper floor with over 90 sqm including a south-facing roof terrace, even though certainly a smaller one would have sufficed. But it was important to me that they should not have one iota less living quality than we did. Had I not had this attitude, I would have rather looked for a nice apartment to rent nearby for them. It is a frequent topic or problem here in the forum that older people are wanted to be included in the house, but they usually are not given equally comfortable apartments, for whatever reason.
I would tell the architect that the older person should have a really nice apartment there, equally comfortable, with sunshine and also some view as well as adequate rooms; it certainly doesn’t have to be lavish but on equal footing in terms of living quality.
Your own must-have list including many calculated tax advantages here is endlessly long, which is completely fine; however, I have not seen a list (even if smaller) for the needs of the older person.
Having to hear that mine was even worse before would not be nice and would make me, as an older person, immediately drop out of further planning.

A cellar remains a cellar. If you want and can design it like in the pictures, that would help. But the floor plan is still not good.

Assuming the granny flat is removed. What about the floor plan on the ground floor / upper floor needs improvement?

Living space in the cellar is expensive. The exterior facilities really cost money.

I’m trying to understand this by the price per m2. Simplified 40m2 granny flat at 3000 EUR / m2 = 120k + stairs 20k + terrain 25k? plus excavation and disposal (which I consider already included with the cellar) and maybe some buffer = 165 - 190k. Is that about right?
Then that would effectively be around 4-5k/m2.

How high is the groundwater level?

Quote from the geotechnical report

No waterlogging, layered water or groundwater was encountered during the drilling process. An impact of groundwater on the building is not to be expected. However, after heavy rainfall and/or correspondingly wet weather periods, an increased occurrence of waterlogging as well as an increased supply of water from surface water must be expected.

... (and more)...

There is no influence of groundwater or floodwater at the building site. The determination of a design water level (HGW/HHW) is not relevant for planning in this case. An impact of groundwater or floodwater on the building is not present in this case. According to the water and soil conditions at the building site, waterlogging effects on the building must be expected due to poorly permeable soil with kf < 10^-4 m/s.

Attached is the summary.

Basically: First of all, thank you all for all the input. It’s not like anything here surprises us so far. We’ve already discussed everything ourselves and partly pushed things back and forth.

[*]Omit the granny flat in the basement, move the house closer to the garage
[*]Omit the basement altogether (we like this option the least at the moment because then we would have to move the utility room and other spaces entirely upstairs)
[*]Swap living/dining -> then the kitchen would be in the southwest and the living room in the southeast
[*]Access the "all-purpose room" around the corner or via two doors
[*]Expand the study with a 1m bay window facing the street.

At the moment, we just can’t find a good solution where everything somehow fits. That’s why compromises obviously arise here and there. We also have the feeling that the architect is at the end of his rope. What would you suggest? Back to square one and start over?

And regarding the detailed questions:

If you raise the basement, the safety measures are reduced. With the architect’s design, raising it only slightly works because the garage at the boundary must comply with the 3m height. Without the framework, you can raise it more.

Assuming the framework would be removed. What would be the basic recommendation then? Max out the height and go up +80cm?
And what would be the approach? Model the 80cm above the 5m line or only partly above it plus 1-2 steps?

With a granny flat, the parapet would then be about 1m low and closer to the photos we based our idea on. Would that fundamentally change the situation?

My thought would be a small extension as a granny flat, probably in the northwest, to keep the access simple and level. Behind it, the main house possibly on split-level for an optical and felt separation – all without a basement. However, it’s hard to assess whether the plot is sufficient. I don’t see measurements except the sparse 650 sqm from #1.

Look here. The initial post only allows 10 pictures. Next time I’ll happily compile them as a photo album instead of releasing them bit by bit.
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Split-level makes the fun expensive, more complex and prone to problems again. Why not just use a basement?
If we separate it by one level in the garden, we just shift the modeling from left to right. And then the granny flat is a compromise with lighting because northwest and so is the main apartment. That sounds like no fewer compromises to me.

I understand that you want more garden and therefore prefer to plan the basement. But in the end, you have neither the garden, since it gets eaten up by excavations, supports, and railings nor a proper apartment where you want to live, since nobody really likes living in the basement. So be careful with poor compromises, because in the end, you only spent money and actually have nothing.

Assuming there was no granny flat. What poor compromises do you see in the ground floor and upper floor?

Because the room with a width of 285 cm is only suitable for a double bed at most, but a wardrobe no longer fits in.

We discussed in one draft whether to extend the room with a 1m bay window towards the street. Investment probably around 10k. My understanding is rather that you all agree that the room will never be suitable as a bedroom in old age. So it remains a study/guest room/storage space.
Actually, we wanted to place such a room in the northeast of the house. But then the all-purpose room would be more or less in line and that fits us even less.

I would omit the pantry and then swap living/cooking so that cooking/eating is at the terrace. You have the basement for the larger supplies. Windows would need to be adjusted a bit.

We also did a quick and dirty version with the architect once, but kept the current study as is. From a usability point of view, we find it difficult to omit the pantry. Currently, we have a small chamber outside and must walk 20 steps in one direction every time. The way to the basement would be even longer.
In the end, we mainly decided against it because of the living room’s orientation towards the southwest and would rather accept the somewhat longer direct route from the island to the terrace.

I think this is fairly easy to answer. If you want to live together with someone in the same house, each party should equally be able to look forward to the newly created living space. Just ask yourself whether you would move into this basement room with family and accept the identical arguments. Surely not!
I myself lived like this for over 20 years, and my parents first had their apartment finished upstairs with over 90 sqm incl. a south-facing roof terrace, even if smaller would have also sufficed. But it was important to me that they should have no less living quality than we do. If I hadn’t had this basic attitude, I would have preferred to look for a nice rental apartment nearby for them. It is a more frequent topic or problem here in the forum that elderly people should be brought into the house but mostly are not given equally comfortable apartments for whatever reason.
I would tell the architect that the older person should have a really nice apartment there, just as comfortable, with sunlight and also some view as well as appropriate rooms; it certainly doesn’t have to be generous but equally in terms of living quality.
Your own must-have list including many calculated tax advantages here is endlessly long, which is totally fine; but I haven’t seen a list (even if smaller) for the needs of the older person.
Having to hear that I had it even worse before wouldn’t be nice and as an older person would make me immediately give up further planning.

Isolated, that resonates. You also write these principles in other posts. It’s not that we don’t want it. We simply can’t manage it in three drafts. Maybe we are fixated on the idea from the start that the granny flat should be in the basement. And then compromises simply come about here and there.
If we transfer that to the planning, you probably also made some compromises so that it is acceptable for parents/in-laws. That seems a bit contradictory to me compared to the final product. If we move the granny flat to the ground floor, there’s less garden left. If we split the southeast/southwest flank, again a compromise.

Regarding the basic attitude towards family, the situation from our point of view is different. I claim that the attitude fits. We just don’t derive equality from it. We are at a different life stage. We always assume one person for the granny flat who is in the final stage of life. Now that means < 30 sqm from the 5th floor in the city center. Eventually, it means grandma/grandpa out of a house that is already too big. No siblings, no guests.

The requirements are basically

[*]35-50 sqm
[*]separate entrance for one’s own privacy
[*]own bedroom, currently not available
[*]light in the all-purpose room – and we struggle with that in our case with the drafts
[*]preferably some green space for plants, raised beds
[*]currently no car because they can easily get around on foot
[*]close to family

I have now also gone through all the Claudia-W, MarlenP, and Hausma threads again. Incredible, what input you have provided there :O We are reconsidering what that would mean for us. What I find a little lacking in the threads compared to us is the slight slope. Both neighboring houses use the basement floor. Admittedly, their plots are longer and the building extends further into the slope. With us, it would be right on the boundary. From the northeast side, we can virtually place everything on the ground floor. If you skip the descent/passage, then the granny flat gets the garden behind the garage.

At some point, it means Grandma/ Grandpa 2 have to leave a house that is already too big anyway. No siblings, no guests.

What or who do you mean?

Swap living/ dining -> But then the kitchen is in the southwest and the living room in the southeast.

In the end, we decided against it mainly because of the orientation of the living room towards the southwest.

Why do you think the living room is better placed in the southwest? Do you need most of the light in the sofa corner? Do you need proximity to the terrace for watching TV?
Actually, you need most daylight where you also spend time during the day. In summer, the terrace and garden replace the dining and living area. You only sit on the sofa once the sun has set.
The kitchen belongs to the terrace, where you constantly go from outside to the fridge in summer.

The storage room/pantry is barely replaceable with three tall cabinets given these dimensions.