Single-family house, 1.5 stories, 155 sqm

Hello everyone,
we would like to share our draft with you to get feedback and suggestions for improvement and to identify any potential issues.
With the optimized draft, we want to approach construction companies and request offers. All surveyed architects have a too long waiting time; since we need to apply for funding in spring, that unfortunately would not work time-wise.

What do we want to build?
Single-family house with a maximum of 160 m² according to the living space regulation (so the terrace counts proportionally) to qualify for funding.

Development plan/restrictions
Plot size: 645 m²
Slope: yes, slight. Over the total length of the plot of about 28 m, approximately 1.5 – 2 m rising from the street (south) upwards
Floor area ratio: 0.4
Floor space index: 0.8
Building window, building line and boundary: 2.5 m top and bottom (viewed from the street) is the building boundary, roof overhangs may protrude up to max. 1 m beyond the building boundaries while complying with the setback requirements of the state building code BW. Garages may be constructed outside the buildable areas.
Edge development: Neighbor’s garage west on the border, see site plan. Both neighbors east & west have already built; on the other side of the street south is still a free building plot. North is a field and no development planned.
Number of parking spaces: 2, preferably double garage
Number of floors: 2 possible
Roof shape: freely selectable
Style: freely selectable
Orientation: SW
Maximum heights/limits: max. height of 8.5 m measured from the ground floor floor level to the highest point of the roof construction (for roofs up to 7° only 7.5 m height)
Further requirements: ground floor floor level max. 0.5 m above street level; photovoltaic mandatory (BW), cistern mandatory (approx. 6 m³)

Client requirements
Style, roof shape, building type: classic gable roof house, 30° roof pitch, 1.4 m knee wall
Basement, floors: no basement, 1.5 floors
Number of persons, age: 3 persons, 32, 28, 0
Space requirements on GF, UF:
GF: living-dining-kitchen approx. 45 m², office/guest approx. 10 m², utility approx. 8-10 m², shower bathroom approx. 4 m²
UF (all net room area): bedroom approx. 14 m², bathroom with utility room approx. 16 m², 2x children’s rooms each approx. 16 m²
Office: family use or home office?
Since we currently plan only one child, the office on the GF should serve as a storage & guest room, the second "children’s room" as an office. Guests approx. 15/year, home office approx. 3 days/week
Open or closed architecture: open
Conservative or modern construction: more or less modern
Open kitchen, cooking island: yes
Number of dining places: normal 4, extendable up to 12
Fireplace: no
Music/stereo wall: no
Balcony, roof terrace: no
Garage, carport: yes, double garage if possible with min. 6 x 7 m (WxL)
Utility garden, greenhouse: no
Further wishes/special features/daily routine, also reasons why this or that should or should not be:

[*]From the sofa, the kitchen should not be visible (when sitting on the sofa)
[*]Living-dining area with kitchen should be the "heart" of the house
[*]Shower bathroom and stairs (if possible also guest room) should not be accessible through the dirt area in front of the entrance door
[*]Sufficient cloakroom space
[*]Washing machine & dryer in the bathroom on the UF, because that’s where the laundry occurs, but separated from the children’s rooms by the hallway
[*]Gable or dormer facing southeast (street side) due to the view
[*]Waiver of dormers etc. for cost reasons
[*]Terrace mainly in the southwest to also get evening sun. This will later be roofed with a pergola. A 3 m lift-and-slide door would be my dream
[*]GF with at least 2.5 m room height, UF 2.4 m ok

House draft
Who created the design: Do-it-Yourself
What do you particularly like? Why?

[*]Spacious living-dining-kitchen area, kitchen not visible from the living room
[*]Light-filled living rooms
[*]Subsequent separation of the living room possible by, for example, glass elements
[*]Parking space in the living room available
[*]Modern through open staircase
[*]Stairs accessible from living area (natural path to bathroom or bed)
[*]View axis entrance → garden through window behind the stairs, without having a view of the entrance door from the rooms
[*]Implementation of fundamental wishes (number of rooms, orientation of rooms, functionality, etc.)
[*]Little actual corridor space on the GF

What do you not like? Why?

[*]No separation to the UF possible
[*]“Head clearance” up to the first stair landing critical
[*]Overhang in front of the left children’s room lost space
[*]No window in the shower bathroom on the GF
[*]Dirt corridor & relevant rooms separated
[*]If a second child ever comes, little storage space
[*]Relatively large with approx. 155 m² (-> expensive)
[*]Exterior view, but this is not our main focus for now
[*]Terrace southwest, but possible terrace door for lift-slide element too small (currently 1.5 m), therefore this element planned next to it on the south side (3 m planned)
[*]No pantry, here I would provide a small cabinet & fridge-freezer combo in the utility room if space permits somehow
[*]Very long driveway
[*]Unfortunately relatively close to the neighboring plot in the southwest

Price estimate according to architect/planner: -
Personal price limit for the house, incl. equipment: €520,000 for everything except outdoor facilities, but must be reduced through own contributions.
Preferred heating technology: still open, no fossil fuels possible, probably air-to-water heat pump.

If you have to do without, which details/extensions
can you do without:

[*]Spacious guest/work/storage room
[*]Shower on the GF

can you not do without:

[*]Utility room on the UF
[*]Side entrance to the house
[*]Spacious living-dining-kitchen

Why is the draft the way it is now?
We visited three construction companies, received partly good plans (but too large), and partly standard drafts that did not fit at all. Therefore, we dealt intensively with floor plans and tried to create a draft where we have to make as few compromises as possible. Due to our wish to enter the house from the side and to have the living-dining-kitchen area arranged as an L on the southwest of the house and the two children’s rooms facing south with a waiver of dormers and dwarf gables, we did not find any 1.5-story drafts from, for example, prefabricated house providers.
After many other drafts, in the end, we drew this one, which we basically like best and which is just still okay in size. The bay window for the stairs will certainly lead to additional costs, which we hope to reduce by waiving a flat roof and extending the roof.
The floor height of the GF is only an assumption; the stairs are planned for a floor height of 2.83 m, tread 26 cm, riser 18 cm.

In addition to hints and comments on the floor plan, we also ask ourselves the following questions:

[*]Is the size of the living area including stairs statically possible without problems?
[*]How complicated & expensive would ventilation for the shower bathroom on the GF be?
[*]Is the “head clearance” for the stairs sufficient?
[*]Is it worth having knee wall windows as planned in the children’s room? We see advantages in better light incidence for a small seating area and ventilation options through a tilt window

Thank you already for your help! I am happy to provide any information available to me if needed.
Please be kind, this is my first post and

Over the total length of the plot of about 28 m, it rises about 1.5 – 2 m from the street (south) upwards

Is there a site plan with elevation points or does this slope really extend evenly over the entire length?

What stands out on the plan:

[*]Technical connection room as far away from the street as possible ... and access for cables is built over, either by the driveway or by the floor slab
[*]Driveway very long = high costs
[*]The position of the stairs I find more than unfortunate, it would be better in the north for a desired southwest orientation of the house.
[*]Considering that space is somewhat tight, an incredible number of corridor or purely walking areas (living/dining area to the stairs) have been created
[*]Staircase in the bay window as planned is probably not technically possible, you would have to see the height section there
[*]Sofa position rather uncomfortable with back to the walking area between floors
[*]Dining table expanded for 12 people then also blocks the access upstairs
[*]Garage with 6 m external width more than tight for 2 cars and bicycles, which then have to be led past the cars.
[*]Where are the garbage bins?

Generally to reconsider

[*]Ventilation concept - controlled residential ventilation
[*]House location on the plot
[*]Side entrance generally requires a small platform or step and this becomes very tight with the driveway to a double garage for 2 cars.
[*]Is photovoltaic planned? East and West?

What don't you like? Why?

[*]No separation from the upper floor possible [*]“Headroom” up to the first landing of the stairs is critical [*]Overhang in front of the left children's room is lost space [*]No window in the shower bathroom on the ground floor [*]Dirt corridor & relevant rooms separated [*]If a second child should come eventually, little storage space [*]Relatively large at about 155 m² (-> expensive) [*]Exterior view, but so far that is not our main focus [*]Terrace southwest-facing, but possible terrace door for lift-and-slide element too small (currently 1.5 m), hence this element planned for 3 m right next to it to the south [*]No pantry, here I would provide a small cabinet & fridge-freezer combo in the utility room if space-wise somehow possible [*]Very long driveway [*]Unfortunately relatively close to the neighboring property in the southwest

If you don't like all that, I can only recommend the trash bin. It needs to be redesigned. Why plan it like this if you already know you don't like it? There are so many floor plans online. Why not take a standard design from a prefab house builder? First start with measuring the plot. Roughly 1.5-2 meters is not enough for planning. If necessary, the geoportal can help. If you want help here, you should show or mention the development plan. Please no link. 155 m² is, in my opinion, not within the budget.

Is there a site plan with elevation points or does this incline really extend evenly over the entire length?

First start with surveying the property. Roughly 1.5–2 m is not sufficient for planning. If necessary, the Geoportal helps.

Thanks to the tip from hanghaus2023 with the Geoportal, I measured and the incline is not completely even. From the street to halfway through the property it is 0.5 m and to the northern end another 0.9 m height difference. Unfortunately, there is no plan.

[*]Technical connection room as far away from the street as possible ... and access for cables is overbuilt, either by the driveway or by the floor slab
[*]Very long driveway = high costs

Unfortunately, that is true, we have noticed it as well. The position of the house and the garage was chosen to have as much south-facing garden as possible and no shadow areas caused by the garage. Would you put the garage in front of the house to create a corridor for the cables next to it?

[*]I find the stair position very unfavorable, with a desired southwest orientation of the house the north would be more suitable.
[*]Considering that space is somewhat tight, an incredible amount of hallway or pure walking areas (living/dining area to the stairs) have been created
[*]Staircase in the bay window as planned is technically probably not possible, you would have to see the height section there
[*]Sofa position rather uncomfortable with the back to the walking area between floors

The stair position definitely does not have to be at the shown position. We have also considered a north orientation, but then we could not find a floor plan that meets the remaining requirements. Positioning in the north always led to a very wide floor plan, which in turn would come at the expense of the terrace area in the west.

The walking/hallway area in the dining/living area is due to the option for a table for 12 people. Of course, not ideal.

Which section would be necessary to make an assessment regarding the implementation of the stairs?

The sofa position could still be adjusted (e.g. under the window).

[*]Garage with 6 m external width is more than tight for 2 cars and bicycles, which then have to be led past the cars.
[*]Where are the garbage bins?

How wide would the garage have to be then?

Regarding the garbage bin location, we had a discussion and came to the conclusion that they will probably be accommodated near the street in a box...

[*]Ventilation concept – controlled residential ventilation
[*]House location on the property
[*]Side entrance usually requires a small platform or a step, and that becomes very tight with a driveway for a double garage for 2 cars.
[*]Is photovoltaics planned? East and West?

Probably decentralized ventilation for cost reasons. Do you have a recommendation here?

House location as described above.

The area immediately in front of the garage should still be leveled to house/garage level, then we wouldn’t need a step anymore, right?

Photovoltaics must be installed according to the obligation in BW, where exactly this is prescribed here, we still need to check carefully.

If you don't like any of it, I can only advise the trash can. It has to be redesigned.

Why plan it that way if you already know you don't like it?

There are so many floor plans online. Why not take a standard design from a prefab house builder?

First start with surveying the property. Roughly 1.5–2 m is not sufficient for planning. If necessary, the Geoportal helps.

If you want help here, you should show or name the development plan here. Please no link.

155 m² is in my opinion not within budget.

The points we mentioned are not things that are no-gos for us, but points where we possibly still see room for improvement or hope for tips.

Unfortunately, we did not find a standard design that fits us better from the many catalogs searched. Suggestions are welcome here.

Can we send you the development plan?

How many square meters do you see within our budget?

First of all, my recognition for your well-prepared thread, and even if the house probably won't be feasible like this. In various places, however, you can see that you have already made a lot of considerations.

How complicated & expensive would ventilation for the shower bathroom on the ground floor be?

That alone would be inexpensive to solve, but if you sensibly install a controlled residential ventilation system, the problem is solved anyway. However, I think the floor plan will be changed many times, so I would only worry about such things when the time comes. My attempt would be to get the central controlled residential ventilation into the budget; if necessary, you have to cut back, but maybe there are other points that can be dropped as well.
In fact, I also see it like , that you might be able to find a suitable floor plan online, since your requirements are not special and the plot does not seem to be a problem, except that it has a north side. Our neighbors also have about north side.

House location on the plot

I also believe that this is an important decision. I wouldn't afford an expensive garage; a generous carport with adjacent storage room can be implemented significantly cheaper and in my opinion also nicer; plus more own work can flow in there, or it can be expanded step by step as money becomes available.
I think the mentioned budget must first be clearly defined, including really all ancillary costs, otherwise they are castles in the air.
I also think it makes sense to at least look at the neighbors’ house placement and also how and what they have solved in some respects and how it looks in reality.

First of all, my respect for your well-prepared thread, and even if the house probably won't be feasible as it is. However, in various places you can see that you have already put a lot of thought into it.

Thank you very much for that – I have indeed already invested a lot of time and have read a lot here in the forum. Do you have some concrete points as to why the house probably won't be feasible?

That alone would be easy to solve, but if you sensibly install a controlled residential ventilation system, the problem is solved anyway. However, I think the floor plan will be changed many times over, so I would only worry about such things when the time comes. My attempt would be to get the central controlled residential ventilation into the budget; if necessary, something else will have to be cut, but maybe other points can be found to reduce.

How much budget should be planned for a controlled residential ventilation system? We had an estimate of 22,500 € from one of the builders; is that realistic? We hoped to save or at least reduce it by using a decentralized ventilation system; another builder spoke of about 8,000 € (but actually letting the exhaust air flow out of the rooms through air outlets – which doesn't sound very energy efficient to me, but I haven't really dealt with ventilation yet).

I actually agree with @hanghaus2023 that you might still find a suitable floor plan online, because your requirements are not special and the plot also does not seem to be a problem, except that it has a north-facing side. Our neighbors also have roughly a north-facing side.

I'll search again for floor plans. However, many have the staircase in the dirty area in front of the front door or the front door on the north side with the living area in the south, both of which are a no-go for us. Nonetheless, we would still appreciate criticism of our floor plan! A garden in the north would of course make everything significantly cheaper, but we actually want to avoid that. The house will stand at 800 meters above sea level, so summers are (still) not so hot and the decision is justified differently than if you live lower.

I also think this is an important decision. I wouldn't afford an expensive garage; a generous carport with adjacent storage room can be implemented significantly more cheaply and in my opinion also more nicely; you can also put more of your own work into it or build it gradually when money is available.

To save costs, we would initially only have the foundation built and build the garage later ourselves, for example as a timber-frame structure. How we will handle the garage roof is still uncertain. Or wait for a promotional garage. A carport would only be an option if it's really impossible, since we have harsh winters at 800 m above sea level and want to avoid scraping.

I think the mentioned budget must first be clearly clarified, including all incidental costs, otherwise it's castles in the air.

We will, if possible, have an appointment at the bank next week to better assess the financing.

By the way, we also received a cost estimate from one builder for 163 m² at 540,000 € including incidental costs (fixed price). This builder has already built about 15 houses in this area and can hopefully assess it quite well.

I also think it makes sense to at least look at the neighbors' house placement and also what and how they solved some things and how it looks in reality.

Most neighbors placed their house far back, and the garage/carport to the right side of the house. Only our direct neighbor still has a few meters of space in the back and placed the garage on the side in front of the house. I'll try to sketch the house in Paint.