Cost estimate, bungalow 130 m2

Hello,

we are planning to build a small single-family house (Baden-Württemberg, south of Freiburg)

No basement, ground floor, currently only an attic (not developed)
Living area about 95 m2
The plot is fully serviced, flat

Strip foundations
Ytong 36.5 cm + exterior plaster + brick slips (external walls)
Ytong 24 cm / 11.5 cm (plastered interior walls, load-bearing / non-load-bearing)
Roof frame (double) with clay roof tiles
Wood beam ceiling insulated from above
PVC windows, standard white doors, patio window with electric shutters
Parquet in all rooms except WC, bathroom, storage room, dining and part of hallway (here of course tiles)
No smart home, very standard electrical equipment

So, nothing spectacular and relatively simple to build. Since a friend of mine is an architect and I work in the construction industry, we can save on planning / building permits. We want to do separate contracts if we can stay within the budget.

My assessment:

Additional construction costs (insurance, surveying, building permit, construction power etc.) 20,000
Excavation for foundations and channels: 10,000
Shell construction (foundations, walls, wood beam ceiling, roof): 130,000
Facade: exterior plaster and brick slips 20,000
Electrical 20,000
Heating 25,000
Sanitary: 20,000
Interior plaster: 20,000
Doors, shutters and windows: 30,000
Bathroom and tiles: 20,000
Parquet: 10,000
Kitchen: 10,000
Outdoor staircase: 5,000
Outdoor area: 10,000 (here we want to do practically everything ourselves)
Painting work: if it’s worth it, we want to do it ourselves

350,000 euros

I have already started sending the specifications to individual companies, but many companies either have no time to prepare a non-binding offer or only in a few months. Separate contracts will certainly be stressful and more difficult to manage, but maybe there will be more quality in the end.

Plans below. Thanks a lot.

Finally, a down-to-earth counterproposal to the increasingly common bigger, more expensive, fancier approach here.

I really like it, also the floor plan.

I consider the cost breakdown plausible overall. Possibly overestimated.

I would estimate incidental construction costs at around €30,000-40,000, and less in other areas.

If you exclude kitchen, outdoor facilities, and incidental construction costs, I would be at about €300,000. That would result in a price per square meter of €3,000. I think €2,500/sqm is achievable with the simple equipment.

Well, to be honest, in my opinion, this is not a typical house in Germany. In the country where we were born, this is a comfortable single-family house for parents with 2 or 3 children. Sounds strange, but we wouldn't feel comfortable in a bigger house. But of course, to each their own.

A developer gave me a flat rate of 400,000 euros for such a house. I think that's quite expensive. I hope to find individual craftsmen and maybe build cheaper (shell construction, interior plaster, screed, heating, electrical etc.).

I have already started sending the specifications to individual companies,

Based on this very, very self-made draft? - that could be a shipwreck of the first order.

350,000 euros

Ridiculously expensive for such a tiny house without extras.

Based on this very, very hand-drawn draft? - that could be a first-class shipwreck.

Actually, I meant a construction description with roughly defined areas and volumes. That should be sufficient for a rough cost estimate.

Calculation according to DIN 276 looks very unreliable to me, since the current construction costs are very high.