ᐅ Floor Plan Design for a Single-Family Home of Approximately 250 sqm with a Separate Granny Flat
Created on: 26 Jan 2025 21:52
C
CornforthWhite
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
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:
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:
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.
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.
W
wiltshire28 Jan 2025 09:58There are always several viable solutions. This is a place to exchange good ideas. It would be a shame if it turned into a "who is right" debate.
CornforthWhite schrieb:
I understand that the entrance to the main apartment here is not very popular, but you'll have to explain to me what exactly is wrong with the porch (which, on a corner plot, is supposedly even more problematic than on the previously misunderstood plot). It’s quite simple—for me, a porch always serves as a statement, preferably facing the street, often with "rocking chairs." Here in the north, without direct access, I just find it an unattractive entrance situation, almost as if the house had shifted on the plot.
For the entrance to the granny flat or secondary unit, I think it doesn’t really matter whether it is on the right side of the plot (east), from the bottom of the plan (south), or the top of the plan (north).
W
wiltshire28 Jan 2025 12:02haydee schrieb:
I think some people will want to enter the house through the terrace. It looks like an entrance if you don’t see the official one. I also believe this will be a common shortcut—which isn’t a problem if you are aware of it. Therefore, I wouldn’t recommend installing patio doors here, but rather a proper exterior door suitable for everyday use.
kbt09 schrieb:
Simply put, a porch always makes a statement to me, often facing the street, often with "rocking chairs." The front porch is part of the culture in many American homes. It provides a way to welcome people without inviting them fully inside, which has many advantages, especially in rural areas. This style has also spread into more densely populated towns. And yes, with larger houses, such an entrance can serve as a “statement” feature. In this particular design, I wouldn’t consider it as having a “statement” function. If the view toward the street remained unobstructed, people could sit there like Statler and Waldorf in their balcony.
K
Kreisrund1 Feb 2025 15:26CornforthWhite schrieb:
I have a nice view of the garden from the dining area; in the sofa area, I actively prefer not to have large glass surfaces and find it cozier when it feels more enclosed. Not everyone has to like it that way, but it’s not as unusual a layout as is sometimes claimed here and was actually copied from a very expensive architect-designed house that we really like. So it seems a professional once considered it an acceptable design choice.If that’s how you want it, go for it! Personally, I can imagine that in very hot countries, having a dark and cool room as a retreat could be a real benefit. That might even explain the architect’s decision. Right now, in the north German winter, I appreciate every ray of light in the living area and wouldn’t like to spend much time in such a room during the day. But that could be very different where you are… For me, a house is definitely inseparable from the location where it is built.