ᐅ Semi-detached house in Hamburg with a general contractor on own land, two plus full attic floors, no basement
Created on: 26 Jul 2025 12:27
1
1689owen
I’m looking for feedback on anything we might have overlooked. Tips on processes and organization are also helpful. (Details about the location, plot, and contractors involved will be shared later to keep things anonymous for now.)
We want to build a duplex and hire a general contractor (GC) for this. Each party has about €40,000 (approximately $44,000) available. The scope of self-performed work will differ slightly between the two parties but will mainly be limited to painting (including plastering and all related work) and flooring (excluding bathrooms). The attic may possibly be finished as self-performed work.
We have a few requirements:
According to the plans, we may build two full stories. We want to retain as much garden space as possible and, for this reason among others, would like to add a fully functional attic. By “fully functional,” we mean it can be used as living and working space and forms its own separate part of the apartment—not an open area connected to the stairwell (for example, the parents’ bedroom would be here). We were advised that having a concrete floor between the upper floor and attic would be sensible to achieve this. The attic could also be raised with a knee wall (dormer wall), which would greatly improve the interior height. Since the plans don’t specify maximum ridge, eaves, or gable heights, it will likely be restricted only by required setback distances. The setback to the neighboring plot is currently set at 3 meters (about 10 feet) for driveway, bike storage, and garage as border construction. This leaves a good garden area on the other side of the house.
kfw300 program:
This is very helpful for financing, almost essential for us. However, it comes with certain requirements that may cause additional costs. Which parameters would you recommend adjusting here?
Current status:
We have discussed financing preliminarily and set a budget framework. We already own the land. We are currently in talks with several GCs (ranging from smaller architecture firms, medium-sized companies, to larger firms like Baudirekt). We plan to decide on a GC in about a month. The options each GC offers will understandably influence our decision. We also still need to clarify whether we truly need and can afford a fully finished attic or if a pitched roof attic that could be finished later would suffice. A basement would probably be more expensive and provide less livable space than a full attic, so it is no longer a serious option. We plan to consult two or three more GCs to get feedback on possibilities and pricing.
Please feel free to ask any questions! This is already a lot of help. Maybe there’s even some additional advice out there. Thanks!
We want to build a duplex and hire a general contractor (GC) for this. Each party has about €40,000 (approximately $44,000) available. The scope of self-performed work will differ slightly between the two parties but will mainly be limited to painting (including plastering and all related work) and flooring (excluding bathrooms). The attic may possibly be finished as self-performed work.
We have a few requirements:
- Each party: 2 adults (bedroom, office) + 3 children (individual bedrooms)
- Total house footprint around 165m² (approximately 1,775 sq ft). A preliminary building inquiry has already been made.
- Noise protection necessary due to aircraft noise.
- Full attic living space
- kfw300 program
- Solid construction
- Brick facade
- Pitched roof
- Central ventilation system
- For both parties: rooms should not be too large (e.g., child’s room 10m² (110 sq ft), office 8m² (86 sq ft)); only one large open area for living and kitchen.
- Each half of the building should be easily separable in the future into an accessible unit (basement) and an apartment (upper floor + attic).
According to the plans, we may build two full stories. We want to retain as much garden space as possible and, for this reason among others, would like to add a fully functional attic. By “fully functional,” we mean it can be used as living and working space and forms its own separate part of the apartment—not an open area connected to the stairwell (for example, the parents’ bedroom would be here). We were advised that having a concrete floor between the upper floor and attic would be sensible to achieve this. The attic could also be raised with a knee wall (dormer wall), which would greatly improve the interior height. Since the plans don’t specify maximum ridge, eaves, or gable heights, it will likely be restricted only by required setback distances. The setback to the neighboring plot is currently set at 3 meters (about 10 feet) for driveway, bike storage, and garage as border construction. This leaves a good garden area on the other side of the house.
kfw300 program:
This is very helpful for financing, almost essential for us. However, it comes with certain requirements that may cause additional costs. Which parameters would you recommend adjusting here?
Current status:
We have discussed financing preliminarily and set a budget framework. We already own the land. We are currently in talks with several GCs (ranging from smaller architecture firms, medium-sized companies, to larger firms like Baudirekt). We plan to decide on a GC in about a month. The options each GC offers will understandably influence our decision. We also still need to clarify whether we truly need and can afford a fully finished attic or if a pitched roof attic that could be finished later would suffice. A basement would probably be more expensive and provide less livable space than a full attic, so it is no longer a serious option. We plan to consult two or three more GCs to get feedback on possibilities and pricing.
Please feel free to ask any questions! This is already a lot of help. Maybe there’s even some additional advice out there. Thanks!
N
nordanney26 Jul 2025 18:441689owen schrieb:
However, a general contractor (GC) who follows their own procedures might prefer to make their own (re)planning, which could cost me extra, so I end up paying twice in some parts and stuck with the additional costs. Or where am I mistaken? Yes. If you tell them you want the planned house, then that’s what you will get. The GC is just an executor who does what you want. The one who pays calls the shots. And if you want 17 rooms of 8sqm (86 sq ft) each in the house (and the architect designed it that way), then that’s what the GC will build. The GC doesn’t care whether your house ends up ridiculous or outstanding. They just build it.
1689owen schrieb:
Maybe like this (all sqm figures are rough estimates):
Ground floor: living-dining area with kitchen (30 sqm (323 sq ft)), utility room (8 sqm (86 sq ft)), guest bathroom (one party with shower) (5 sqm (54 sq ft)), the rest (14 sqm (151 sq ft)) divided between hallway and another room (guest/office). 30 sqm (323 sq ft) for 5 people is already quite a tight squeeze.
I’m not a fan of sticking to fixed square meter targets – a poorly planned 15 sqm (161 sq ft) room can offer less usable space than a 10 or 12 sqm (108 or 129 sq ft) room. But a dining table definitely needs space around it for seating, a family sofa should be bigger than the KLIPPAN from Ikea, and a kitchen needs adequate cabinets as well as counter space.
However, you’re forgetting the staircase. 8 sqm (86 sq ft) utility space might be enough for a KfW40+ standard, but you’ll probably also need space for laundry and a broom.
1689owen schrieb:
and a proper heating system, etc. Without that, it wouldn’t be a livable space.
ypg schrieb:
Challenge issuedActually, I initially intended to discuss general aspects first. Now we have some figures (and the estimate is only to show that we have considered square meters per floor). Based on what you, @ypg, wrote, one room would definitely need to be moved to a higher floor. That would mean the attic (roof space) would have to be used as living space. And this thread is, among other things, precisely about the question of whether and how we need, can afford, or can design the attic for living purposes. Also, about any tips you might have on how to proceed with this.
Regarding other matters (e.g. KfW 40+ standard and financing framework), I have already written something above; I am waiting for comments on that first.
nordanney schrieb:
Yes. If you tell the general contractor that you want the planned house, then you will get it. The GC is just an agent who does what you want. The one who pays calls the shots.Interesting. Do Baudirekt and Viebrockhaus, for example, consider themselves such agents? I would assume that Viebrockhaus only builds its own homes. Or are they not general contractors and I have confused the terms here?N
nordanney26 Jul 2025 19:451689owen schrieb:
Interesting. Do they consider themselves … etc. as subcontractors? I would assume that Viebrockhaus, for example, only builds its own houses. Or are they not general contractors, and I have mixed up the terms here? They are mainly providers of their own houses. The typical general contractor is a construction company or a carpentry firm. Usually local providers.
Viebrockhaus & Co.: Prefabricated house manufacturer
General contractor: Local carpenter
For clarification
nordanney schrieb:
The typical general contractor (GC) is a construction company or a carpentry firm. Preferably local providers.
[...]
For clarification Thank you!
Then there is also the question of whether we should approach a traditional GC or a company that builds their own houses with our ideas. Maybe some adjustments could lead to something more affordable that still meets our requirements to some extent. (Viebrockhaus would probably not be an option for us – by the way.)
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