Building description for a single-family house with a basement

Hello,

I am currently in the planning phase for the construction of a single-family house. I would like to briefly list the construction description of a potential company here.
What additional costs should still be expected? Is the construction description usable, or do I still need to pay attention to important things?

Construction Description

Scope of Services:
Preparation of the Construction Site

[*]Complete site setup including construction power, construction water, WC, crane, machines and equipment, alignment grid, etc.
[*]Remove topsoil and store it on the side for later use
[*]Excavation of soil for building pit soil class 3-5 (easy to difficult soils to excavate)
[*]Sewer connection on the building plot
[*]Wastewater and rainwater pipes inside and outside the building, drainage and sealing
[*]Water and gas connection from the meter device inside the building

Shell Construction

[*]Strip foundations in concrete C 20/25 assuming load-bearing soil without groundwater
[*]Concrete slab C 20/25, incl. reinforcement, on capillary-breaking gravel layer and separating layer
[*]Exterior walls ground floor / upper floor made of highly thermally insulating porous warm masonry bricks 42.5 cm thick, other wall constructions possible
[*]Walls in basement / ground floor / upper floor made of solid brick masonry (soundproofing between rooms!!!)
[*]Impregnated rafter roof truss, wooden cladding with diffusion-open boarding membrane, roof tile covering in red or anthracite
[*]Gutters and flashings in titanium zinc
[*]Precast concrete element ceilings with in-situ concrete topping above basement / ground floor / upper floor
[*]Wooden beam ceiling above upper floor at knee wall
[*]Chimney; Schiedel/Erlus brand chimney moisture-resistant or equivalent
[*]Reinforced concrete balcony with sealing and sloped screed, fine stoneware tiles

Interior Finishing

[*]White plastic windows, triple glazing with thermal insulation glass Ug=0.5 with safety fittings, 3 surrounding seals, floor-level windows in the lower area with fixed glazing
[*]Basement: Plastic windows with triple glazing
[*]Window sills inside granite, outside aluminum white anodized
[*]Aluminum front door of choice with stainless steel push handle, security door fittings and lever protection
[*]Roller shutter box thermally separated, revision opening outside, roller shutter made of plastic with ventilation slots in all living rooms with horizontal lintel
[*]Plastering: outside silicone resin plaster colored, full-surface mesh smoothing on machine lightweight plaster. Inside: lime-cement or lime-gypsum plaster
[*]Central heating for hot water, in ground floor and upper floor, gas condensing boiler, weather-controlled regulation, night setback, hot water storage, photovoltaic and solar preparation (=lines + control cables to upper floor), pellet heating, heat pumps, solar technology, residential ventilation etc.
[*]Also combined with gas heating, Kermi flat panel radiators with thermostat valves, underfloor heating, towel radiator in the bathroom
[*]Sanitary facilities in white, acrylic corner bathtub or shaped body bathtub 80*180. Acrylic low-profile shower tray with built-in thermostat mixer tap. Single-lever fittings (concealed). Frost-proof external water tap (self-draining)
[*]Electrical installation: supply from house connection protection of utility company, extensive equipment (e.g. 70 sockets), door intercom system, empty conduit system for antenna / IT etc., Busch-Jäger Reflex SI program, foundation earth electrode according to VDE
[*]Interior doors with real wood veneer, surface natural beech, alternatively CPL doors (lightfast, scratch-resistant, stain-resistant, abrasion-resistant) with rounded edges, stainless steel lever handle set or surcharge
[*]Wall and floor tiles, or fine stoneware tiles of choice, laying included in total price
[*]High-quality floor coverings according to plan. Prefinished parquet, laminate
[*]Elegant cantilevered staircase solid beech, wooden handrail, stainless steel rods or surcharge
[*]Thermal insulation made of mineral fiber in the upper floor between rafters (23 cm), vapor barrier, drywall panel covering, hatch
[*]Washable solvent-free interior paint, reinforced concrete ceilings with textured wallpaper structure in the ground floor
[*]Floating cement screed on thermal insulation in the apartment and basement
[*]Garage similar to residential building

Additional Services (included in the purchase price)

[*]Building application and submission plan
[*]Local construction supervision and site management
[*]Certificate of airtightness of the building
[*]Blower door test as quality proof
[*]Energy certificate with corresponding evidence (thermal protection, system technology)
[*]Thermal protection according to the new energy saving ordinance

Thank you very much for your effort.
Stephan

May I ask what criteria you used when selecting the GUs?

It is difficult to answer because we do not know everything you want that is not mentioned in the description.

Things that immediately stand out to me
- Utility connections (BU works "from the meter")
- Transport and disposal of the excavation
- Is the excavation suitable for backfilling? If not, the basement must be filled with bulkheads
- What does "tiles of choice" mean? Have you given a price range or does the tile purchase completely come out of your own pocket and the BU only handles the installation? Same for the floor
- There is practically nothing about the basement. Who takes care of the insulation in the basement? Light wells? Basement stairs? Electrical work in the basement?
- More detail on the electrical topic. 70 sockets in how many rooms? Make a room program of how many sockets you need where (e.g. kitchen 6 free sockets, stove, fridge, dishwasher) and total them. Only then can it be assessed if 70 sockets are suitable for you. Same for lamps
- Regarding heating, it is not clear to me where underfloor heating and where radiators will be installed. Both are mentioned
- "Garage analog" is also very unclear. You will hardly have parquet flooring installed there
- Surveying and soil report

It's just a rough overview. The details are missing.

Example:
Empty conduit system for antenna/IT The antennas and network cabling including sockets are added on top. How many meters of empty conduit and what thickness are included? Not that the builder assumes one empty conduit from the utility room to the living room and you want empty conduits for the whole house. Are there flush-mounted boxes at the end of the empty conduit?

This runs through the entire description!

A construction description without plans is incomplete.

Thank you very much for your tips.

Regarding the question of what a general contractor (GU) needs to bring with them for us:
Solid construction
Regional provider (For me, this simply has the advantage that the companies, electricians, heating engineers, etc. know our systems. If I ever want to remodel something or something breaks, they are familiar with it)
Good experiences (We can look at houses in the immediate vicinity and talk to the homeowners)
Budget (Many prefabricated house companies are simply way too expensive; we have about €300,000 just for the house construction. You don’t get far with the big providers if you want a basement. Additionally, we leave a €50,000 safety reserve for anything unforeseen. If we don’t need this money, it either goes into the outdoor facilities or into special repayments on the loan)

On the phone, we already talked about a floor plan for a 150 sqm house + basement and the price would be around €315,000 (so €2100 per sqm including the basement, including flooring, kitchen, bathroom). We were advised to calculate €350,000 as a safety margin because no soil survey, etc. has been done yet. After the call, we decided that 150 sqm is too large for us and will talk about a house floor plan of 138 sqm on Wednesday (if I base it on the €2100 per sqm, I hope to get down to €290,000)

We are building without underfloor heating because we personally find it uncomfortable. I know no one believes us, but we simply want normal radiators.

Primarily, I was looking for a rough assessment. We have the first personal meeting with the construction company on Wednesday and I just wanted to clarify many things that I might not have noticed. That’s why I gave you the construction description like this.
It already helped me because I can already ask about landfill costs, sockets, network sockets, basement, flooring budget, etc. on Wednesday.

If you think of anything else that should definitely be asked, I would be very happy.

Best regards
Stephan