ᐅ Floor Plan Design for a Single-Family Home of Approximately 250 sqm with a Separate Granny Flat

I already feel a bit anxious writing this, anticipating the inevitable criticism of our design, but I’m posting it anyway. We struggled somewhat with the software, so much of the presentation is still quite provisional. Our main goal is to find out whether what we’ve basically planned could work. We’re primarily looking for feedback on functional planning errors. Style critique is sure to come since our design is unlikely to suit most people’s taste here—but that interests us less (we like what we like, and that probably won’t change). Although tastes vary, I’ve learned a lot from other threads recently and hope that “the usual suspects” might also take a look at our design. Thanks in advance!

Development Plan / Restrictions

Plot size: 960 m² (10,333 sq ft)

Slope: no

Floor area ratio: 0.2, maximum buildable footprint however <175 m² (1,883 sq ft)

BUT: the 1977 Building Use Ordinance applies

• § 19 IV: Ancillary structures according to § 14 are not counted towards the allowable footprint. The same applies to balconies, loggias, terraces, and structural elements as far as they are permitted within setback areas or distance zones under regional law (here: Bavaria) (…).
• § 21a III: Covered parking spaces and garages are not to be counted towards the allowable footprint as long as they are less than 0.1 of the plot area.

Floor space index: -

Building envelope, building line and boundary: 5 m (16 ft) from the road on the south and west, 3 m (10 ft) from neighbors on the north and east

Edge development: no

Number of parking spaces: 1.5 per dwelling unit

Number of storeys: 1 + attic

Roof style: no fixed style, but roof pitch regulation with 2 options

Option 1: 22–26 degrees

Option 2: 33–44 degrees

Architectural style: no specification

Orientation: flexible

Maximum heights / limits: in red the official restrictions of the development plan, in green the generously granted exceptions we are aware of (several times approved). The neighbors recently submitted a building application aiming for slightly higher eaves and knee wall heights—this will serve as a reference for us.

For roof option 1 (22–26 degrees pitch): ridge height max. 8 m (26 ft) (or 8.15 m / 27 ft), eaves height max. 4.0 m (13 ft) (or 5.20–5.30 m / 17–17.5 ft), knee wall max. 115 cm (45 in) (or 2.20–2.30 m / 7–7.5 ft)

For roof option 2 (33–44 degrees pitch): ridge height max. 10.5 m (34 ft), eaves height max. 3.5 m (11.5 ft), knee wall max. 40 cm (16 in) (exceptions probably possible but no figures known)

Definition of eaves height: Top of rough ground floor slab to intersection of exterior wall with the bottom edge of the rafters

Definition of knee wall: Top of rough attic floor slab to intersection of exterior wall with the bottom edge of the rafters

Client Requirements

Architectural style, roof shape, building type: a new build that does not look like a typical new build

Basement, floors: no basement (high groundwater level, no living space planned underground), two full stories (which are effectively possible due to generous exceptions from the development plan)

Number of people, age: my mother (70+), my husband and I (late 30s), 2 cats, 1 dog, 1 child planned

Space requirements on ground and upper floors: On the ground floor a self-contained apartment for my mother and kitchen / living / dining / utility for us;

Office: 2 offices (both approx. 50% and 80% remote work)

Guest stays per year: about 2–3 weeks

Open or closed layout: open on the ground floor

Conservative or modern building style: conservative

Open kitchen, kitchen island: yes to both

Number of dining seats: 6–8

Fireplace: yes (gas fireplace)

Music/sound system wall: no

Balcony, roof terrace: balcony would be nice

Garage, carport: spacious double garage

Utility garden, greenhouse: rather no

Other wishes / special features / daily routine, including reasons why some things are desired or not:

• Covered terrace / loggia / outdoor seating with reliable but as discreet as possible insect protection (lakeside location, regular mosquito issue) & fireplace (probably gas as well)
• A rather unpopular opinion here, but we explicitly do not want roller shutters or venetian blinds. We currently have them despite many south-facing windows and never use them (feels like a vault). Instead, we plan air conditioning (powered by photovoltaics) and larger trees.
• Gas stove (I just can’t get comfortable with induction)
• Washing machine & dryer on the upper floor
• In one office, a small niche for an exercise bike (turbo trainer)

House Design

Who designed it: DIY

What do you like most and why?

- Style inspired by classic American Colonial architecture

- Living area centered around the fireplace

- Porch with insect protection, fireplace & privacy

- Kitchen island with plenty of workspace

- Small “secondary kitchen” to temporarily hide dirty dishes / cooking mess

What do you not like? Why?

I wouldn’t exactly say “dislike,” but we have doubts about the following points:

• Passage between garage and house might be too narrow?
• Entrance and staircase possibly not spacious enough?
• Staircase: can’t properly design it in the software, but according to a stair calculation tool it should work. Is the space requirement adequate? Are the asymmetrical runs a problem?
• Bedroom in the self-contained apartment is borderline small
• Bathrooms: enough space?
• Utility/technical room: large enough?
• Could a mechanical ventilation system with heat recovery possibly be installed in the crawl space attic?

Personal price limit for the house, including fittings: we’re budgeting €3,000 per m² plus additional costs and landscaping, but have significant equity and thus some flexibility upwards; also plan a lot of personal work.

Preferred heating technology: heat pump with geothermal probe

If you have to give up something, which features/finishes
- Could be sacrificed: balcony
- Cannot be sacrificed: no compromises on the self-contained apartment

Why is the design like it is now?

We originally wanted to buy a house with old-style charm but found nothing suitable. Although we like modern, minimalist architecture, it’s not for us personally.

I’ll help a bit with the images.

Thank you very much, ypg! May I quickly ask where my mistake was? In the rules, I only find this: "Images must be uploaded online exclusively via the forum's own upload function." Sorry, I’m obviously blind and missing something....

CornforthWhite schrieb:

The style inspired by a classic American Colonial

Looks like someone has been watching too much HGTV.

Yes, that's really an unusual style nowadays—but it’s definitely refreshing to see something like that.
Provided it’s allowed where you are?!

@Steffi33 built this style as a bungalow. It’s also shown here in the forum. Steffi will probably be happy to share a link to her thread.

CornforthWhite schrieb:

Passageway between garage and house possibly too narrow?

Yes! At least in my opinion. But what bothers me more is that the entrance has to be clearly signposted so everyone can find it. How is the secondary apartment supposed to be accessed on foot or by vehicle? Only the northern neighbor benefits from the elaborate entrance...

How many parking spaces do you need per dwelling unit where you live?

CornforthWhite schrieb:

We are planning with €3000 per sqm plus additional costs plus landscaping,

€3000 per sqm (approximately $280 per sq ft) applies to a basic standard house without many corners, with a normal number of windows and standard fittings.

CornforthWhite schrieb:

Thank you very much, ypg! May I briefly ask where my mistake was? In the rules, I only found this: "Images may only be uploaded using the forum’s own upload function." Sorry, I seem to be blind and must be missing something....

You can find the upload option under your post window while you are writing (on the right: reply preview, highlighted in blue), on the left it says attach file, highlighted in white.

This is an interesting non-standard house design. I’m trying to imagine how it would feel to live there and for whom. The "American" influences are clearly noticeable – a lot of private space for the master bedroom, the living room as part of the passageway to the kitchen, spaciousness in some areas as if enclosed space costs nothing, and a classic arrangement of kitchen, dining, and living areas – plus the covered terrace.
I can imagine that living in this house would be very comfortable, and I am familiar with the "American way of life" from personal experience, even though I wouldn’t build like this myself. Please take the following points just as input.

1. The granny flat (or accessory dwelling unit) has some peculiarities that many would dislike. It is very narrow and has no coat storage area. Above the living room, a child lives, and there is a room with a bicycle – is that a fitness roller? I’m concerned about noise.

2. The living area does not receive direct natural light. If that is intentional, the design is perfect in that respect.

3. The butler’s pantry is a great feature, but depending on its intended function it might be a bit small.

4. The window in the utility room looks appropriate from the outside but poses a challenge for installing the necessary equipment inside. I would have to “fit that out” carefully.

5. The bathroom area follows the “en suite” concept but the proportions are somewhat tight. The child shares a large bathroom with guests and has a long way to get there.

6. Given the generous master bedroom, I would consider placing a bathtub, for example, near the large balcony door.

7. The child’s bedroom might be a bit dark. I always recommend planning windows from the inside out, rather than based on the façade view – but I understand the visual requirements for the house as a whole. Try to add slightly larger windows on both sides of the gable of the granny flat.

8. In Germany, we cannot build houses of this form under standard conditions. In the USA, with traditional wood-frame construction (which only roughly compares to our timber construction), it’s quite different. Assuming you can manage with €3000 per square meter is ambitious. Since you are financially flexible, you can consider these points later. From my perspective, forming a clear intention should come first.

9. The passageway between garage and house is completely fine as long as there is a wider access to the garden elsewhere.

10. The round gable windows are really nice.

This could become a very beautiful house. A wood façade would suit it very well.

hanghaus2023 schrieb:

I don’t understand why people want to disregard rules.

For me there are no issues with the attachments – not even in the first post. Why make it an accusation immediately?

ypg schrieb:
Someone must have watched too much HGTV.

Yes, this is a really unusual style nowadays – but it is refreshing to see something like this.
As long as it’s allowed where you are?!

I do actually enjoy watching HGTV sometimes, but my inspiration comes from elsewhere. I lived in a similar house myself many years ago and liked it a lot. The zoning plan is flexible here, so there’s nothing against it.

ypg schrieb:
@Steffi33 built this style as a bungalow. It can also be seen here in the forum. Steffi will probably be happy to share her thread.

I’ve also already seen and admired that house here, including the very pretty garden.

ypg schrieb:
Yes! Just to my taste. But I find it much worse that the entrance has to be clearly signposted so everyone can find it. From where is the secondary apartment supposed to be accessed or entered? Only the northern neighbor benefits from the elaborate entrance…

The secondary apartment will have access and a parking space from the other street (this is a corner plot) right along the boundary with the eastern neighbor. We just haven’t added that to the plans yet. It should be possible to get permission – there was already a preliminary building inquiry for the plot with two single-family homes, each with access and parking: one in the northwest (where the garage is now) and one in the southeast next to the neighbor.

Ideally, not many people should come to the main entrance – we are introverted and value privacy. Mailbox and camera will be placed right next to the garage at the entrance. I understand your point about the hidden entrance that’s not very visible, but primarily I want to enjoy it myself with nice flowerpots and so on.

We’ll probably need to reconsider the space required for the access. How wide do you think it should be, at a minimum?

ypg schrieb:
How many parking spaces do you need per dwelling unit?

1.5 parking spaces per dwelling unit, so 3 in total.

ypg schrieb:
€3000/sqm applies to a standard cookie-cutter house without many corners, with a typical number of windows and standard fittings.

As I said, we are still quite flexible regarding budget, but want to do all interior finishing work ourselves. We already have a turnkey offer for a very similar (smaller) house at €3300/sqm (with quite reasonable fittings) from a provider who, according to previous clients, stayed well within budget. So I don’t think we’re that far off if we do a lot of the work ourselves. My husband is very skilled with his hands, and we already have good experience from previous renovations.

ypg schrieb:
You’ll find the upload function below your posting window while you write (on the right: reply preview, highlighted in blue), on the left “attach file” in white background.

Thank you!

wiltshire schrieb:

This is an interesting non-standard house design. I’m trying to imagine who would live in it and how. The "American" influences are quite clear – a lot of private space for the master bedroom, the living room acting as a passageway to the kitchen, generosity in some areas as if the enclosed space costs nothing, and a classic layout of kitchen, dining, and living areas – plus the covered terrace.
I can imagine that living in this house would be very comfortable, and I am personally familiar with the "American way of life," even though I wouldn’t build that way myself. So please take the following points just as input.

1. The granny flat has some peculiarities that many might dislike. It’s quite narrow and lacks a cloakroom or entryway. A child lives above the living room, and there is a room with a bike – is that an exercise roller? I’m concerned about noise levels.

First of all, it’s nice that not everyone completely dislikes the design!

Are the rooms in the granny flat really that narrow? I’m currently comparing it with our old older apartment, which mostly had rooms of similar dimensions, and I found it quite livable. But we might be mistaken. We liked that you could see straight through the granny flat when the bedroom door was open. My mother really likes the granny flat as it is, but of course it should also be rentable later on, so your point is definitely valid. I’m not sure right now how to redesign it without disrupting everything else, but we will think about it. The missing cloakroom entryway also bothers me, but I’m not yet sure how to address that. Maybe a small vestibule instead of the little porch outside the door, and reducing the house size somewhere else to gain the necessary square meters.

Unfortunately, there is no child yet, but that’s also a good point. Maybe it really would be better to swap rooms. The bike is an exercise roller. My husband has used one before (with a noise-absorbing mat underneath) even in an old period apartment, and the neighbor didn’t hear anything, but we should definitely check if that could be an issue – good point.

wiltshire schrieb:
2. The living area does not get any direct daylight. If that’s intentional, then the design fits perfectly.

We are fully aware of that and it’s fine for us; perhaps even cozier for relaxing on the sofa, watching movies, etc.

wiltshire schrieb:
3. The "Butler’s Pantry" is a great feature, but depending on its intended use, it might be a bit small.

Yes, we also find it borderline small, but probably just okay for what we need. It will have a second sink to hide dirty dishes from view. Also, the fridge/freezer and dishwasher (to reduce noise and odors) will go in there. The tall cabinets currently shown on the exterior wall will have to be removed for that. Plus, it should allow a quick drop-off of groceries from outside so you don’t have to carry bags through the living room. It doesn’t need to do much more, as storage should be reasonably sufficient in the kitchen.

wiltshire schrieb:
4. The window in the utility room looks good from outside but will pose challenges fitting in all necessary equipment inside. I would "lay out" that room carefully.

Yes, we definitely need to do that. We roughly estimated what needs to fit in there, and it seemed possible, but it still needs a detailed check. The window will probably have a fixed-closed roller shutter and mainly serves the exterior aesthetics.

wiltshire schrieb:
5. The bathroom area reflects the "ensuite" concept but has somewhat unusual proportions. The child shares a large bathroom with guests and has a long way to get there.

Originally, we planned a kids’ bathroom above the flat’s bathroom, which would be between the child’s room and the guest area. Maybe we’ll reconsider that option. Having both bathrooms in one corner worked better for the other rooms. We will definitely review this again.
Do you think the bathrooms overall are too small? We are definitely not "wellness-type" people who want a large spa-style bathroom or spend hours there, but of course, we don’t want to build a relatively large house and then have bathrooms that feel too small.

wiltshire schrieb:
6. With such a spacious master bedroom, I would consider placing a bathtub, for example in front of the large balcony door.

Many people would probably love that, but having a bathtub in the bedroom is not our thing at all.

wiltshire schrieb:
7. The child’s room could be a bit dark. I always recommend planning windows from the inside out rather than based on the façade view – but I understand the aesthetic demands for the house as a whole. Try to place slightly larger windows to the right and left of the gable on the granny flat.

We had once related the room size to the window area and thought it was okay (don’t remember the numbers right now), but we will revisit the two small windows.

wiltshire schrieb:
8. In Germany, you cannot build such house shapes at standard conditions. In the USA, with classic wood frame construction (which is only loosely related to our timber construction), it’s quite different. Assuming a budget of 3000€ per square meter is ambitious. Since you are financially flexible, you can consider this later. I think forming your intentions first is the right sequence.

We have a quote for a stylistically quite similar house from a larger Swedish house manufacturer (production in Sweden, but they have several completed projects in our area) for 3200€ turnkey. They explicitly offer "New England" style. So I think our price won’t be too far off. We want to contribute own work, e.g., closing walls, plastering, painting, laying parquet and tile floors, preparing electrical work, and designing and buying photovoltaics ourselves, only having it installed, so hopefully that will save some money.

wiltshire schrieb:
9. The passage between the garage and the house is perfectly fine as long as there is a wider access to the garden somewhere else.

Wider access to the garden is not a problem; there are several from different sides.

wiltshire schrieb:
10. The round gable windows are really nice.

This could become a very beautiful house. A wooden façade would suit it very well.

Thanks! It is indeed planned to have a white wooden façade with narrow horizontal boarding.