ᐅ Urban villa with gable roof, including a separate apartment, a finished basement, built to KfW 40+ energy efficiency standard, and geothermal heating system

Good evening!

Keywords to start: townhouse with pitched roof, KfW40+ energy standard, geothermal heating with ground probe, photovoltaic system at least 10 kWp + 5 kWh battery storage, living basement with external stairs and laundry room + basement room for a granny flat, converted attic. Turnkey price 580,000€ including basement and carport.

This year we will be building a house with a granny flat for renting out to the parents-in-law just outside Hamburg. The floor plan is a preliminary draft created by ourselves. We hope to get valuable ideas and suggestions from you to optimize the layout, since we have become too close to the project. We are not yet fully convinced by the townhouse design, as it feels a bit impersonal. However, the lack of sloped ceilings and the large attic space provided by the pitched roof are appealing. We are considering adding a veranda facing the street and window shutters to give some character. The interior will be designed in a rustic country house style.

We already have a quote, which we plan to accept. However, the floor plan and possibly the house type may still be adjusted.

We have attached screenshots of the development plan, infrastructure plan, house graphic, floor plan, cross-section, and garden plan.

We look forward to your ideas and thank you in advance for your time!

Development Plan / Restrictions
Plot size: 774 sqm (8,331 sq ft)
Slope: No
Plot ratio: 0.25
Floor space index: Unknown
Building envelope, building line, and boundary: See development plan screenshot
Number of parking spaces: 3 mandatory, minimum 45 sqm (484 sq ft)
Number of floors: 2
Roof type: Any, between 15° and 50°
Architectural style: No restrictions
Orientation: No restrictions
Maximum heights / limits: Eaves height max. 6 m (20 ft), ridge height max. 9.5 m (31 ft)

Owners’ Requirements
Style, roof form, building type: No fixed specification. Townhouse has the big advantage of no sloped ceilings upstairs and large attic space if built with pitched roof rather than hip or pyramid roof.

Basement, stories: Living basement, ground floor, first floor, and converted attic
Number of occupants, ages: 2 adults in early 30s and 1 child; we plan to have at least 3 children.

Space requirements on ground floor and first floor:
Main residence: At least 55 sqm (592 sq ft) living/dining/kitchen + hall + shower bathroom ~70 sqm (753 sq ft)
First floor: 3 children’s bedrooms each at least 13 sqm (140 sq ft) + bathroom 13 sqm (140 sq ft) + corridor ~62 sqm (667 sq ft)

Granny flat: At least 75 sqm (807 sq ft), 2 bedrooms of 13 sqm (140 sq ft) and 10 sqm (108 sq ft), living/dining/kitchen about 35 sqm (377 sq ft), one bathroom at least 6 sqm (65 sq ft), and a guest toilet of 2 sqm (22 sq ft)

Office: Family use or home office? Both
Overnight guests per year: 20
Open or closed layout: Rather closed; floor-level windows only on first floor facing west and northwest (due to street in southwest, none facing south)
Conservative or modern construction: Rustic
Open kitchen, kitchen island: Yes
Number of dining seats: 10 with extendable table
Fireplace: Yes, but planned for later due to cost
Music/speaker wall: No
Balcony, roof terrace: Not desired
Garage, carport: Carport
Kitchen garden, greenhouse: “Self-sufficiency” garden and chickens

Two terraces facing southwest and northwest.

House Design
Who designed it: Us, the owners.
What do you particularly like? Why? The granny flat only has access via the laundry room and its own basement room accessed by external stairs. A lot of usable space was gained on a small footprint through the basement and pitched roof. We like the two terraces which provide afternoon and evening sun.
What don’t you like? Why? “Square, practical, good.” A townhouse feels a bit impersonal, but 1.5-story design offers too little space in the attic and the sloped walls are inconvenient.
Price estimate according to architect/planner: Turnkey 580,000€ according to the quote, including living basement, geothermal heating with ground probe, photovoltaic 10 kWp + 5 kWh battery, KfW 40+
Personal price limit including equipment: 600,000€
Preferred heating system: Geothermal heat pump with ground probe

If you had to give up something, which details or expansions
Could you give up: Kitchen island, possibly the pitched roof but rather reluctantly
Cannot give up: No basement is a no-go

Why is the design as it is?
Standard design by planner? Own design

What is the most important/fundamental question about the floor plan in 130 characters?
We hope to receive valuable ideas and suggestions for optimizing the floor plan.

Hello,

I’m not an expert, but two things stand out to me.
If you need three parking spaces, usually tandem parking (parking spaces placed one behind the other) is not allowed. You should check this.

How large is the house supposed to be? To me, it looks like about 12×10m (39×33 feet)? That might be tight regarding the floor area ratio (FAR). 774×0.25 = 193
193 - 45 (parking spaces) - 3×15 (small terraces) - 120 (house) = -17, and you still need to account for paths, a shed, and a chicken coop. Here, too, I would check to what extent construction over the allowed area is permitted.

Best regards

The offer seems unbeatable for the building volume as drawn!

A rough calculation would be about 110 sqm (1,184 sq ft) of living space each for the ground floor and first floor, plus nearly 60 sqm (646 sq ft) of basement with living quality. That totals 280 sqm (3,014 sq ft) at a minimum of 2,000 €/sqm (about 186 USD/sq ft), currently more likely in the range of 2,300–2,500 €/sqm (around 215–234 USD/sq ft) for a standard build, not KFW40+ standard, with additional basement area and a roof that can at least be converted later.

Heat pumps with drilling add roughly 15,000–20,000 € (about 16,500–22,000 USD) extra, photovoltaic systems with battery storage are likely in the same range, and additional insulation and other windows would be extra on top.

Is this a fixed price or an architect’s estimate? I don’t want to crush anyone’s dreams, but this sounds too good to be true before walls and everything else are finalized.

Parking spaces lined up one behind the other are sometimes accepted, but not guaranteed.

Jan-Philip schrieb:

We already have an offer, which we will accept. However, the floor plan and possibly the house type are still being refined.

We don’t know exactly what it will be yet, but we’ll sign just to be safe. 😳

Jan-Philip schrieb:

City villa with gable roof, KfW40+ standard, geothermal energy with ground probe, photovoltaic system at least 10 kWp plus 5 kWh storage, basement with external stairs and laundry room plus cellar space for a separate apartment, finished attic. Turnkey price including basement and carport: 580,000 € .

With that stated square meterage, no way!

Jan-Philip schrieb:

Fireplace: yes, but later, since it’s expensive.

Will it be cheaper later? 😎

I can hardly make anything out on the plans. Leave out the laminate, provide clear dimensions, and please show the levels separately.

If I add up the floor areas of the ground floor, upper floor, and attic, I already reach 320 m² (with basic fittings x €2,100 / m² = €672,000) plus a basement living area, plus KfW40+ standard, plus photovoltaic system and carport for €580,000?

Good luck!

I’m asking, where is north? Is that information included in the zoning plan? How did you come up with the idea to design a house like this? I don’t see an eave height of 3.5 m (11.5 ft) anywhere. You should start over. Or better yet, have someone design it who actually knows what they’re doing. 🤨

MM1506zzzz schrieb:

When I add up the floor areas of the ground floor, upper floor, and attic, I already get 320 sqm (3,444 sq ft) (with standard finishes x €2,100 / sqm = €672,000) plus a finished basement, plus KfW40+ standard, plus photovoltaics and carport for €580,000?

Good luck!

That changes if you eliminate a floor. :p