ᐅ Floor Plan Design for a Single-Family House with a Basement on a Sloped Site
Created on: 22 Mar 2025 13:41
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57Christian
Hello everyone,
we are currently planning to build a single-family house with a basement on a sloped site and would appreciate your feedback.
Development plan / restrictions
Plot size: 517 sqm (approximately 5,567 sq ft)
Slope: yes
Site occupancy index: 0.3
Floor area ratio: 0.3
Number of parking spaces: 0/1
Number of floors: 1.5
Roof type: gable roof
Maximum heights / limits
Other requirements: roof pitch 28-45°. Knee wall height 75 cm (30 inches), defined slightly differently
Client requirements
Basement, floors: basement + ground floor + attic living space
Number of people, age: currently 3 people (2 adults + 1 child). Planning should include child #2.
Space requirements on ground and upper floors
Office: family use or home office?
Overnight guests per year: not relevant, occasional
Open or closed layout: rather open
Conservative or modern design: rather modern
Open kitchen, kitchen island: yes, kitchen island if possible
Number of dining seats
Fireplace: currently under discussion
Balcony, roof terrace: terrace facing south + terrace facing west planned
Garage, carport: 1 garage, with space next to it for carport / garage (optional, future)
House design
Who designed it: general contractor from the area
What do you like especially? Why? Open living area. All requirements accommodated. Option for a second garage.
What don’t you like? Why? Currently considering removing the second bathroom in the attic and instead adding a shower on the ground floor.
Price estimate according to architect/planner: 500,000 excluding land, additional costs, civil engineering, and landscaping.
Preferred heating technology: heat pump
If you have to give up something, which details / extensions
- can you give up: separate bathroom for the children in the attic
- can’t you give up: open living area, large bathroom upstairs
Why is the design like this? It is the first design from the contractor. Other plans were partly similar.
we are currently planning to build a single-family house with a basement on a sloped site and would appreciate your feedback.
Development plan / restrictions
Plot size: 517 sqm (approximately 5,567 sq ft)
Slope: yes
Site occupancy index: 0.3
Floor area ratio: 0.3
Number of parking spaces: 0/1
Number of floors: 1.5
Roof type: gable roof
Maximum heights / limits
Other requirements: roof pitch 28-45°. Knee wall height 75 cm (30 inches), defined slightly differently
Client requirements
Basement, floors: basement + ground floor + attic living space
Number of people, age: currently 3 people (2 adults + 1 child). Planning should include child #2.
Space requirements on ground and upper floors
Office: family use or home office?
Overnight guests per year: not relevant, occasional
Open or closed layout: rather open
Conservative or modern design: rather modern
Open kitchen, kitchen island: yes, kitchen island if possible
Number of dining seats
Fireplace: currently under discussion
Balcony, roof terrace: terrace facing south + terrace facing west planned
Garage, carport: 1 garage, with space next to it for carport / garage (optional, future)
House design
Who designed it: general contractor from the area
What do you like especially? Why? Open living area. All requirements accommodated. Option for a second garage.
What don’t you like? Why? Currently considering removing the second bathroom in the attic and instead adding a shower on the ground floor.
Price estimate according to architect/planner: 500,000 excluding land, additional costs, civil engineering, and landscaping.
Preferred heating technology: heat pump
If you have to give up something, which details / extensions
- can you give up: separate bathroom for the children in the attic
- can’t you give up: open living area, large bathroom upstairs
Why is the design like this? It is the first design from the contractor. Other plans were partly similar.
K a t j a schrieb:
So it seems that one of us is still struggling with the elevations. If you want a terrace behind the house and another one on top of the garage, through which patio door do you plan to access the rear terrace? From the attic? Or do you intend to excavate the hill behind the house and end up sitting in a huge hole?
I sketched it out:
Assuming you place the garage in the basement and align the height with street level, then the basement would be completely embedded in the hill. Above that would be the ground floor, which would still be more than half covered by the hill. A terrace at the back would then be more accessible from the attic. (Note: these are just sketches to get a sense of the slope)
[ATTACH alt="Christian-Straßenansicht.jpg"]90914[/ATTACH]
[ATTACH alt="christian westseite.jpg"]90913[/ATTACH]
[ATTACH alt="christian ostseite.jpg"]90912[/ATTACH]
Of course, the driveway doesn’t necessarily have to be at street level. The car can handle some height difference as well. But we’re probably talking centimeters rather than meters. (Maybe someone here who’s a car enthusiast can tell us the maximum slope a vehicle can manage without scraping?)
Please correct me if I’m misreading the slope. I’m estimating a height difference of 7m (23 feet) across the property. @hanghaus2023 Could you take a look? You seem to have experience interpreting "slopes."
How have the neighbors built? Do they also have two terraces behind and next to their house? May I ask which software you used for modeling?
H
hanghaus202324 Mar 2025 11:51Thank you @K a t j a, I completely missed your post.
A 35% slope is quite steep.
What does the reference height of 368.77 m (1,209 ft) refer to? I probably overlooked the eaves height restriction??
A 35% slope is quite steep.
What does the reference height of 368.77 m (1,209 ft) refer to? I probably overlooked the eaves height restriction??
57Christian schrieb:
That should allow for a maximum of 2 or 3 meters (6.5 to 10 feet) further back.What do you mean by that? The car clears 80cm (31.5 inches) over 5 meters (16.5 feet). I think that’s already close to the limit. The ground floor is exactly at the rear (southern) ground level. The depth of the south terrace will have to be fully excavated, and the hill stabilized accordingly.
Well, that sounds plausible to me at first, except for the budget.
ReXel83 schrieb:
May I ask which software you used for the modeling? That is "Architect 3D Ultimate." However, the version is quite old, from about 10 years ago.
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57Christian24 Mar 2025 19:29The car has to climb 80cm (31.5 inches) over 5m (16.4 feet). I believe that’s already close to the maximum. The ground floor is exactly at the rear (southern) terrain level. The depth of the south-facing terrace will therefore need to be fully excavated and the slope retained.
Well, that sounds reasonable to me, apart from the budget. Exactly. That’s what I meant with the 20% gradient. (80cm (31.5 inches) over 5.5m (18 feet)) and then another 2-3m (6.5-9.8 feet) behind the house.
We are well aware that the earthworks will be expensive. So far, we have received estimates ranging from 40,000 to 60,000.
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57Christian24 Mar 2025 19:3357Christian schrieb:
So far, we have a few initial drafts from other providers. One design that we actually liked is attached. However, in the attic floor, everything feels a bit tight due to the second bathroom. We would probably adjust that area.
Of course. We thought this should be possible here. Access past the house, past the front door, into the garden. In all the other previous designs, the front door was located in the basement on the eaves side. That would have meant always taking the stairs from the basement to the ground floor to get to the garden.
The terrace above the garage is just an additional feature. The main terrace faces south, that is, at the back of the house.
What does that mean? I thought you always have to maintain a 3m (10 feet) distance from the neighboring property unless you have a special permit.
Yes, that was how the other plans were implemented as well. We are still unsure which option makes more sense for us.
Yes, that’s a good point. Right now, we assume we will mostly enter through the garage, but we need to reconsider that.
I agree. It hadn’t occurred to us before. Thanks.
Regarding the price: So far, it has only been communicated verbally. But we know of a similar house built by this general contractor within this price range.
The knee wall definition is attached. The development plan states WA + I + o I understand that we should fundamentally revise the plan from the first post. Are there any major inconsistencies or essential changes we should make in the other version I shared?