ᐅ Single-Family Solid Construction House with 142 m² Living Area – Questions About Floor Plans and Construction Costs

Hello everyone,

After browsing the forum a bit and mostly reading along, I would like to share our building project and ask for your opinions on our floor plan idea and the roughly calculated costs so far. The house will have the following key features:

• Solid construction detached single-family house with approximately 142 sqm (1,528 sq ft) of living space and a gable roof
• No bay windows/balconies etc.
• Building location: Saxony/Chemnitz
• A "normal single-family house" for 4 people plus a guest/office room
• Slightly sloping plot from north to south – about 700 sqm (7,535 sq ft) in size

We have put together the following floor plan, which best matches our current ideas:

What do you think? Some users have mentioned that it is not ideal for the staircase to be right next to the front door. I can understand the argument about dirt being tracked in. However, this layout seems to us to be the best option in terms of minimizing space used by the entrance area and stairwell. Increasing the house’s external dimensions would also significantly increase costs.

Regarding the guest room, we prefer to have it on the ground floor. We are also thinking ahead to when we get older and would then have a potential bedroom on the ground floor. That is also why there is an additional shower in the guest bathroom on the ground floor.

We have not given much thought to the windows yet. The windows shown on the floor plan are therefore not final, and we would appreciate any ideas or suggestions.

Concerning the overall costs, we would like your opinion on how realistic the following breakdown is:

205,000 € house price (= 1,450 €/sqm (135 USD/sq ft) – offer already received)
30,000 € additional building costs
15,000 € specification buffer + extras
10,000 € materials for outdoor facilities, mostly done by ourselves
-------
260,000 € total costs excluding land costs

Do you see any potential to reduce these costs? It all seems a bit high to us overall. We would also be grateful for any further suggestions.

Regarding the floor plan:
Ground floor: I find the solution with the staircase in the hallway area ideal. The dirt brought in is not an issue for me—perhaps also because we have a small entrance vestibule and do not walk around the house with shoes on (a no-go for us).
I would suggest, if you don’t have a basement, possibly placing the utility room adjacent to the kitchen, with access from the outside via the garage/carport. We considered partly using the utility room as a pantry. For the dining/living area, be careful not to have a too narrow, elongated layout, as in my opinion, this can lead to 1) a lot of wasted space and 2) difficulty in spatially separating the living and dining areas; an offset layout (e.g., with a bay window) looks nice, but of course, this is just MY opinion.

Upper floor: There isn’t much against it, but from what I understand so far, a slanted wall angled along the way should be avoided as much as possible. I can’t assess the impact on the structural engineering, but it doesn’t look aesthetically pleasing either.

Costs: I think the house price is realistic, but the question is what is included: KfW70 standard? Brick or plaster façade? Shutters? Manual or electric? What kind of windows (e.g., floor-to-ceiling yes or no, tinted yes/no)? Solar for hot water? Sanitary fittings from Villeroy & Boch or generic brands? Wooden or concrete staircase? Is everything else standard? I would say that for €1,450 per square meter (around $1,575 per square yard), you can reasonably expect a certain level of equipment.

Construction additional costs (NBK) are realistic; we budgeted €22,000 (approximately $24,000) and are currently on target or even below. For exterior work, I would estimate around €20,000 (about $22,000), including carport and outdoor fencing. That’s based on my experience.

The staircase is probably too short. 15 steps x 26cm (10 inches) = 3.90m (12.8 feet).
The orientation doesn’t fit at all. On the nice south side, there are the bathroom, guest toilet, and utility room.
The slanted wall is also not acceptable. Walls at 45° should be avoided, but a 70° wall is definitely not an option.
I also have doubts whether a single load-bearing wall like that will be sufficient.

You should include the windows and the interior layout/furnishing in the planning right from the start.
Only then can you see if the floor plans work well both inside and in the external elevations.

Your cost estimate is still missing at least the materials for flooring and painting works.

Self-drawn... Do you have an architect? What kind of design is this?

I also think the space for the staircase is too small. The guest room will likely be too small to be used as a double bedroom later on.

I find the slanted wall on the upper floor quite problematic, and the bathroom layout is not ideal either. When you enter, you immediately face the shower, which you’re not even sure fits there (due to the roof slope?), and the rest of the space is largely wasted.

I believe Baumann was referring to the basic aspects, meaning the general layout. It should be clear that the staircase doesn’t fit and that lengths and widths might need to be adjusted. However, this doesn’t require changing the fundamental layout. That’s how I understood it. The floor plan seems to have been created with MySweetHome or another free software. That’s also how we approached the matter.

@Baumann: Do you have a fixed price per square meter with free floor plan design, or is that how the 1450€/sqm (per square meter) comes about?

Thank you all for your opinions. I’ll start by quoting aytex:

aytex schrieb:
I think baumann was referring to the basic elements, meaning the general layout. It should be clear that the staircase doesn’t fit and that lengths and widths might need adjustment. However, the fundamental layout doesn’t have to change. That’s how I understood it. The floor plan seems to have been made with MySweetHome or some other freeware. That’s the approach we took as well.

Exactly. We are still very early in the planning phase. The floor plans were created with the program SweetHome3D and are obviously not accurate down to every centimeter. They are primarily intended as a basis for the general room layout. And arranging the rooms, especially when you want to include a guest room, is not so simple.

aytex schrieb:
I think the house price is realistic, but the question is: what exactly is included? KfW70 standard? Brick or plaster façade? Shutters? Manual or electric? What kind of windows (e.g., floor-to-ceiling or not, tinted or not)? Solar thermal for hot water? Sanitary fixtures from Villeroy & Boch or generic? Wooden stairs or concrete stairs? Everything else standard? At €1,450 per square meter (approx. $135 per square foot), you should expect a certain level of equipment.

KfW70 standard is not included, plaster façade, manual shutters, windows not yet decided, air-source heat pump, although we want gas combined with solar thermal (which reduces the price somewhat), recessed wooden stringer stairs, brands for sanitary fixtures not yet discussed, painting and flooring work including materials are included, everything else standard, although “standard” is always relative. I think something can still be achieved for the €1,450 per square meter (approx. $135 per square foot), or additional features can be added for that price.

Musketier schrieb:
The staircase is probably too short. 15 steps x 26cm (10.2 inches) = 3.90m (12.8 feet). The orientation doesn’t work at all. On the beautiful south side are the bathroom, guest WC, and utility room. The angled wall is also not good. 45° walls are already to be avoided, but a 70° wall is a no-go. I also doubt that a single load-bearing wall is enough.

You should incorporate windows and living area design/furniture into the planning from the start. Only then will you see if the floor plans work both inside and in the external views.

Your cost breakdown still misses at least the materials for flooring and painting work.

The staircase is meant to be quarter-turn. I thought 3m (9.8 feet) length would be sufficient. We had measured something similar once at a show home’s example staircase.

You’re right about the room orientation. I initially wanted to mirror the ground floor rooms (along an east-west axis). However, we plan to attach a double carport on the south side of the building (otherwise it doesn’t really work elsewhere). That would block the southern sun anyway.

The angled wall can definitely be removed if it helps with the structural engineering. We would discuss that further with the architect. I intend to upload floor plans with furniture, but I’m not at my PC right now. Regarding painting/flooring work, see my earlier comments.

backbone23 schrieb:
The guest room will probably be too small to serve as a master bedroom later on.

I also find the angled wall upstairs terrible, and the bathroom is not ideal either. When you enter, you walk directly toward the shower, and it’s unclear if it even fits there (roof slope?!). Otherwise, there’s a lot of wasted space.

You’re right, the guest room wouldn’t be a large bedroom for later use. We are also not entirely happy with the bathroom. Do you have an alternative suggestion? In general, finding the right floor plan is not easy. Changing one room immediately affects the adjacent rooms, which in turn affects the next room, and so on.

aytex schrieb:
@Baumann: do you have a fixed price per square meter with free floor plan design, or how do you arrive at the €1,450 per square meter (approx. $135 per square foot)?

Originally, we asked the builder for 130 square meters (approx. 1,400 square feet) before deciding to add a guest room. The offer, broken down, was almost exactly €1,450 per square meter (approx. $135 per square foot).