ᐅ Single-family house with 190 m² living area and a 55 m² basement apartment, situated on a gentle slope

Hello everyone,

I have planned a house here that largely meets our ideas and requirements. However, we are still unsure about the exterior appearance. Costs and technical reliability also play a role in this decision.

Description:

• 1.5-story construction
• Plot size: 1,150 m² (12,379 sq ft)
• Living area: approx. 190 m² (2,045 sq ft)
• Granny flat: approx. 55 m² (592 sq ft)
• Building size: 10.75 m wide and 15 m deep (35 ft 3 in by 49 ft 3 in)
• Due to the plot width of 19 m (62 ft 4 in), the double garage is integrated into the house but structurally separated.
• Garden orientation: East-Northeast
• Built with an architect and individual contracting of builders

Two variants have emerged that differ mainly in the roof and roof shape:

• Setback floor with flat roof and parapet
• Setback floor with shallow pitched roof (16°) and eaves

For variant 2, I expect additional costs of about €20,000 to €30,000 due to the extra roof structure, the absence of a concrete ceiling, and the relatively expensive roofing materials.

Visually, we prefer this variant, and it also offers better protection against moisture.

However, this layout is quite unusual. Since I have been dealing with it for some time, I might have gotten used to it – therefore, I am interested in your opinion on this.

The facade could be entirely executed as an external thermal insulation composite system (ETICS) in white, or the basement level could be clad in brick (red-black or light gray-black) – an additional cost of about €25,000.
The eaves will be clad from underneath, with no exposed wood.

I designed the draft myself and created a 3D model (in countless variations), and have since hired an architect. However, this architect has other ideas that we do not like – so that part is currently a bit challenging.

In addition, I would appreciate your assessment of the costs.
I have currently budgeted €780,000 for construction and €120,000 for additional costs. The plot is already owned.

Thank you in advance for your constructive comments.

Andixxx schrieb:

I designed the plan myself and created it in 3D (in countless variations) and have now hired an architect. However, the architect has different ideas that we don’t like – so things are a bit stuck at the moment.

Also, I would appreciate your assessment of the costs.
I have currently budgeted €780,000 for construction and €120,000 for additional costs. The plot is already owned.

Thanks in advance for your constructive comments.

I can understand that. Designing it yourself and then possibly showing it to the architect? I’m actually glad that the architect has their own ideas. But without knowing the architect’s plans, what can one say? Structurally, it doesn’t seem fully thought through. Is the area below a terrace or a carport?

Some information seems to be missing that the questionnaire could clarify.

https://www.hausbau-forum.de/threads/grundriss-planung-unbedingt-vor-beitrag-erstellung-lesen.11714/

Please include the zoning plan / development plan and an elevation drawing. No links, as they are not allowed here.

Andixxx schrieb:

I designed it myself and created countless 3D versions, but now I have hired an architect. However, their ideas don’t appeal to us… that’s where the problem lies.

I find it difficult to evaluate the design, meaning the floor plan, because I’m missing dimensioned drawings — not the bird’s-eye view, but the 2D layouts. At first glance, the structural planning doesn’t seem well thought out. Also, I notice a built-in technical room? A too narrow? walk-in closet, a guest bathroom? without windows, so it’s also built inside rather than facing outside... these are technical flaws that should be avoided professionally. Right from the start, there’s a lot that could be improved. The problem is that you have spent so much time with your design that it’s hard to let go because you’re attached to it.

There is a better subforum for floor plan discussions here:
https://www.hausbau-forum.de/forums/grundrissplanung-grundstuecksplanung.237/
And @hanghaus2023 has also posted the link to the related questionnaire.

And yes: taking work away from a professional usually doesn’t make sense, since they have much better tips, studied options, and practical experience that a layperson, even if they can use a software or tool, doesn’t have. Experimenting is fine, but the architect should have free rein.

Andixxx schrieb:

I would also like to hear your opinion on the costs. I have planned 780,000 for construction and 120,000 for additional costs.

It definitely looks quite complex. In addition to the 245 sqm (2,637 sq ft) of living space, there’s also the double garage, which adds usable area. Visually, the house doesn’t match the standard construction method that you would estimate at 3,000€/sqm (approximately $280/sq ft). So, the 780,000€ (roughly $870,000) is probably insufficient.

I reviewed the photos and the post again.

Andixxx schrieb:

For option 2, I calculate additional costs of 20 to 30 thousand euros due to the extra roof structure, the missing concrete ceiling, and the relatively expensive roofing.

...which I now consider quite minor given the overall construction budget.

Andixxx schrieb:

The facade could be entirely insulated with ETICS.

I would not use ETICS. We have ETICS ourselves, which was the go-to solution for low-budget construction 12 years ago. It has proven problematic. Therefore, I would recommend a monolithic construction method.

Andixxx schrieb:

Garden orientation east-northeast

Honestly, I cannot tell from the photos what the original terrain slope is. Is this a sloped plot due to the design? Is that a retaining structure on the side, or does it simply mark the end of the visualization? Is the secondary apartment designed because of the slope or artificially exposed? Will material be filled in or excavated? Since none of this is explained, it also raises questions about the room orientations and the location of the garage.

Here are additional details about the building project:

Development Plan/Restrictions
No development plan
Plot size: 1150 m2 (12378 sq ft)
Slope: Street on the right about 1.6 m (5 ft) lower, rear about 3 m (10 ft) lower
Floor area ratio (FAR):
Plot ratio: 0.4
Building envelope, building line, and boundary: Depth just under 25 m (82 ft)
Adjacent buildings: Old building on the left and a detached house planned on the right as well
Number of parking spaces: 3
Number of floors: 1
Roof design: not determined
Style: Modern
Orientation: Garden facing East-Northeast
Maximum height/limits: Based on neighboring buildings approx. 8.5 m (28 ft)

Homeowners’ Requirements
Style, roof design, building type: Modern
Basement, floors: Yes
Number of occupants, age: 2, 50 years
Space requirements for ground floor and upper floor: 190 m2 (2045 sq ft)
Office: Family use or home office? Office room, hobby room, guest room
Number of overnight guests per year: 30
Open or closed architecture: Open
Traditional or modern construction: Traditional
Open kitchen, kitchen island: Yes
Number of dining seats: 6
Fireplace: Yes
Balcony, roof terrace: No
Garage, carport: Double garage and carport
Utility garden, greenhouse: Yes, also
Other wishes/special features/daily routine, including reasons why certain things are desired or not

House Design
Who designed it: Own design with input from architect
What do you particularly like? Why? Open ground floor, entrance area open to above, access to garage, small utility/pantry next to kitchen, basement includes a granny flat initially used as hobby and guest room, large garage and carport, …
What do you dislike? Why? Flat roof … for aesthetic reasons. Low-pitched gable roof was unusual and expensive
Cost estimate according to architect/planner: 825 kEuro total building and ancillary costs
Personal budget limit for the house, including fittings: approx. 900 kEuro
Preferred heating system: Heat pump / fireplace

If you have to forgo something, which details/finishes
- what you can do without: Carport, covered terrace, finishing the granny flat in the basement
- what you cannot do without: Ground floor and upper floor should be completed. Bathroom and outdoor areas handled independently

Why is the design as it is now?
Standard design from planner? No
Which requests were implemented by the architect? Layout of ground and upper floors as well as entrance area
What do you consider particularly good or bad about it? Due to the sun orientation, the garden side faces sunrise and the street side sunset, and the sloping site allows good positioning and layout of the rooms

The property is located on a slope, slanting downwards to the right and to the left. For this reason, there is the possibility to install windows on the right side of the house and to use the right half of the basement as a separate apartment (hobby room, guest room, etc.).

In the overall view with the property for sale, the elevation profile of the plots can be seen. This corresponds to the data from the survey.