Hello! We are in the very early planning stage of our single-family house. Without adding specific connections and electrical planning details yet, we created a floor plan with doors and windows to roughly calculate all the areas. Below, I have listed some cost estimates for which I am quite uncertain and would appreciate some advice.
The plan is to build a single-family house in Brandenburg (near Berlin) with a built-up area of 11.7m * 10.37m (38.4 ft * 34 ft) including a basement with a waterproof concrete shell ("white tank"). The construction style is solid with a high-quality clinker brick facade (with a distinctive color rather than a standard red tone). In terms of energy measures, besides the solid two-shell construction with good insulation (e.g., mineral wool) and correspondingly insulated roof, basement/foundation slab, and windows, only a geothermal heat pump will be installed, which is very well suited for this region (constant year-round ground temperature above 10°C (50°F) from 25m (82 ft) depth). From a cost-benefit perspective, I am not very enthusiastic about photovoltaic or solar thermal systems. Also, we do not want a mechanical ventilation system or similar because we have found them all disturbingly noisy so far (including the one in our current rental apartment), at least I do; my fiancée is a bit less sensitive.
I would now like some feedback on how realistic these estimates are:
Deep drilling approximately 100 meters (328 ft) total = 3,900 EUR
Heat pump, e.g., geoTherm Plus with a seasonal performance factor above 4 = 7,000 EUR
Bamboo parquet approx. 190 m² (2,045 sq ft) = 5,700 EUR
Tiles (approx. 190 m²) including tiled walls and high-quality tiles in the entrance area = 7,600 EUR
Insulating material approx. 250 m² (2,691 sq ft) with 14 cm (5.5 in) thickness = 2,500 EUR
Facing bricks / clinker bricks approx. 250 m² = 7,500 EUR
Poroton perforated bricks + interior plaster approx. 250 m² = 12,500 EUR
Underfloor heating approx. 250 m² (including partial heating of basement rooms) = 12,500 EUR
Basement with waterproof concrete shell approx. 80 m² (861 sq ft) usable area = 60,000 EUR
Windows and doors, roughly 25 pieces = 8,750 EUR
Additional construction costs (utility connections to the street) excluding official fees and construction water/electricity = 15,000 EUR
Altogether, my calculation (which also includes furniture, energy consulting, and similar items) comes to just over 200,000 EUR in material costs. However, as I mentioned, I am still quite uncertain about some of the above estimates.
For labor costs (wages), I have assumed a maximum of 15 skilled workers over a construction period of up to 6 months (with a construction time guarantee) amounting to 180,000 EUR. Is this a realistic assumption? Are significantly more or fewer skilled workers usually involved?
How would you rate the Vaillant appliances?
Thank you in advance for any support!
The plan is to build a single-family house in Brandenburg (near Berlin) with a built-up area of 11.7m * 10.37m (38.4 ft * 34 ft) including a basement with a waterproof concrete shell ("white tank"). The construction style is solid with a high-quality clinker brick facade (with a distinctive color rather than a standard red tone). In terms of energy measures, besides the solid two-shell construction with good insulation (e.g., mineral wool) and correspondingly insulated roof, basement/foundation slab, and windows, only a geothermal heat pump will be installed, which is very well suited for this region (constant year-round ground temperature above 10°C (50°F) from 25m (82 ft) depth). From a cost-benefit perspective, I am not very enthusiastic about photovoltaic or solar thermal systems. Also, we do not want a mechanical ventilation system or similar because we have found them all disturbingly noisy so far (including the one in our current rental apartment), at least I do; my fiancée is a bit less sensitive.
I would now like some feedback on how realistic these estimates are:
Deep drilling approximately 100 meters (328 ft) total = 3,900 EUR
Heat pump, e.g., geoTherm Plus with a seasonal performance factor above 4 = 7,000 EUR
Bamboo parquet approx. 190 m² (2,045 sq ft) = 5,700 EUR
Tiles (approx. 190 m²) including tiled walls and high-quality tiles in the entrance area = 7,600 EUR
Insulating material approx. 250 m² (2,691 sq ft) with 14 cm (5.5 in) thickness = 2,500 EUR
Facing bricks / clinker bricks approx. 250 m² = 7,500 EUR
Poroton perforated bricks + interior plaster approx. 250 m² = 12,500 EUR
Underfloor heating approx. 250 m² (including partial heating of basement rooms) = 12,500 EUR
Basement with waterproof concrete shell approx. 80 m² (861 sq ft) usable area = 60,000 EUR
Windows and doors, roughly 25 pieces = 8,750 EUR
Additional construction costs (utility connections to the street) excluding official fees and construction water/electricity = 15,000 EUR
Altogether, my calculation (which also includes furniture, energy consulting, and similar items) comes to just over 200,000 EUR in material costs. However, as I mentioned, I am still quite uncertain about some of the above estimates.
For labor costs (wages), I have assumed a maximum of 15 skilled workers over a construction period of up to 6 months (with a construction time guarantee) amounting to 180,000 EUR. Is this a realistic assumption? Are significantly more or fewer skilled workers usually involved?
How would you rate the Vaillant appliances?
Thank you in advance for any support!
B
Bauexperte18 Jul 2012 13:07Hello Chris,
That can certainly be considered a standard house – here the building specifications (BB) should provide more clarity. From my experience, however, I am quite confident that my assessment will be very close to reality after the building specifications are adjusted to personal preferences; assuming the actual living area built will be around 200 m² (2150 sq ft).
You are typical German in that regard: when we are told about noises, we actually hear them.
Twenty years ago, skilled craftsmen still installed ventilation slots in the window reveals; nowadays, that is no longer allowed.
Great.
Kind regards
Chris82 schrieb:
For example, I have an offer for a turnkey house with 180 m² (1940 sq ft) including a basement without a waterproof concrete tank for 260,000 EUR.
That can certainly be considered a standard house – here the building specifications (BB) should provide more clarity. From my experience, however, I am quite confident that my assessment will be very close to reality after the building specifications are adjusted to personal preferences; assuming the actual living area built will be around 200 m² (2150 sq ft).
Chris82 schrieb:
Regarding ventilation ... yes, that is currently a major topic of discussion for us. I have not come across a silent system even in model homes (where I believe they make an extra effort to showcase their features).
You are typical German in that regard: when we are told about noises, we actually hear them.
Chris82 schrieb:
However, I must also say that my father has had a solid masonry house for over 20 years (36.5 cm (14.4 inches) external wall, although I don’t know the exact composition).
Twenty years ago, skilled craftsmen still installed ventilation slots in the window reveals; nowadays, that is no longer allowed.
Chris82 schrieb:
But as you correctly say, we will have a professional energy consultant advise us again.
Great.
Kind regards
How airtight is your father’s house? How often and what is cooked, how many people need to shower, and how much laundry has to be dried—these are all factors that influence indoor humidity. If you want to tilt the windows open, simply switch off the ventilation system. This can be done automatically with a pressure monitor or window sensors, or manually via a control panel in the living area (if you prefer not to go down to the basement). You will likely have the system installed in the basement; model homes usually don’t have a basement. Or do you hear the ventilation slots?
Modern houses are built to be extremely airtight, and there is always a risk of mold growth if you have many plants or ventilate irregularly. But as with everything, there are pros and cons.
I also hope you understand that “turnkey” does not always mean the same thing. There are significant differences in what construction companies include under this term. As far as I know, the term is not legally defined or regulated. Be sure to carefully check the building scope description and have it reviewed to see what is missing. Once you know what is missing, ask for the costs and get everything in writing. Anything not documented is considered not agreed upon. People can say a lot during initial conversations.
Modern houses are built to be extremely airtight, and there is always a risk of mold growth if you have many plants or ventilate irregularly. But as with everything, there are pros and cons.
I also hope you understand that “turnkey” does not always mean the same thing. There are significant differences in what construction companies include under this term. As far as I know, the term is not legally defined or regulated. Be sure to carefully check the building scope description and have it reviewed to see what is missing. Once you know what is missing, ask for the costs and get everything in writing. Anything not documented is considered not agreed upon. People can say a lot during initial conversations.
Turnkey does not always mean turnkey – that is truly the case. There are huge differences in some points of the building and service specifications. Especially regarding site excavation, temporary construction power, and water supply, there are completely different commitments or sometimes none at all.
In our apartment building, a ventilation system is installed. It is incredibly annoying. There is no way to turn off the fans (probably because it would negatively affect other apartments, I assume). In rooms with ventilation (kitchen, guest toilet, and bathroom), an extremely loud fan noise can be heard (any chance of hearing fresh air flow is completely lost). I took the trouble to unscrew the cover to take a look. Looking at the filters made me feel sick; they apparently have not been changed since construction (we haven’t lived here long, and the ventilation seemed practical when we moved in to preempt the question of why we took the apartment despite this annoyance). On top of spending an additional 10,000 EUR (around 11,000 USD) on such a ventilation system, there are constant maintenance and servicing needs that don’t require having windows open. With, let’s say, higher-quality systems, it’s not as extreme as in our apartment, but I can still clearly hear a ventilation noise as loud as a typical office PC. If you switch off the ventilation, you hear nothing anymore. So it is not just imagination. Regarding cost savings, you can forget about ventilation systems with heat recovery if you rely on various studies from Fraunhofer and similar institutions. I’m happy to be proven wrong, but with ventilation systems that’s really difficult. Moreover, you often read that ventilation systems can cause the indoor climate to be anything but healthy. For example, the humidity is much too low, which is also confirmed in our apartment. In some rooms, relative humidity regularly drops below 30%.
The windows in my father’s house have wooden frames and are double-glazed with argon filling (U-value approximately 2 W/m²K averaged). The U-value of the building envelope is about 0.4 W/m²K (estimated using AutoCAD Revit). There are no plastic or synthetic parts on the windows except for the seals (regular rubber, I guess). There are few plants, and showers are used normally. After showering or bathing, the window is simply opened. The same applies when running the dryer—the window is tilted (even in rain) or fully open.
In our apartment building, a ventilation system is installed. It is incredibly annoying. There is no way to turn off the fans (probably because it would negatively affect other apartments, I assume). In rooms with ventilation (kitchen, guest toilet, and bathroom), an extremely loud fan noise can be heard (any chance of hearing fresh air flow is completely lost). I took the trouble to unscrew the cover to take a look. Looking at the filters made me feel sick; they apparently have not been changed since construction (we haven’t lived here long, and the ventilation seemed practical when we moved in to preempt the question of why we took the apartment despite this annoyance). On top of spending an additional 10,000 EUR (around 11,000 USD) on such a ventilation system, there are constant maintenance and servicing needs that don’t require having windows open. With, let’s say, higher-quality systems, it’s not as extreme as in our apartment, but I can still clearly hear a ventilation noise as loud as a typical office PC. If you switch off the ventilation, you hear nothing anymore. So it is not just imagination. Regarding cost savings, you can forget about ventilation systems with heat recovery if you rely on various studies from Fraunhofer and similar institutions. I’m happy to be proven wrong, but with ventilation systems that’s really difficult. Moreover, you often read that ventilation systems can cause the indoor climate to be anything but healthy. For example, the humidity is much too low, which is also confirmed in our apartment. In some rooms, relative humidity regularly drops below 30%.
The windows in my father’s house have wooden frames and are double-glazed with argon filling (U-value approximately 2 W/m²K averaged). The U-value of the building envelope is about 0.4 W/m²K (estimated using AutoCAD Revit). There are no plastic or synthetic parts on the windows except for the seals (regular rubber, I guess). There are few plants, and showers are used normally. After showering or bathing, the window is simply opened. The same applies when running the dryer—the window is tilted (even in rain) or fully open.
Dry air can be regulated using an enthalpy heat exchanger. But also by hanging laundry or having many plants.
Talk to people who have such a system—I haven’t met anyone who wasn’t completely enthusiastic about it. I mean personally, colleagues, or similar. You can also experience it firsthand on site.
PS. You can't hear my office PC at all.
Talk to people who have such a system—I haven’t met anyone who wasn’t completely enthusiastic about it. I mean personally, colleagues, or similar. You can also experience it firsthand on site.
PS. You can't hear my office PC at all.
I just read elsewhere that, unlike a general contractor, an architect is not allowed to offer a fixed price. I don’t quite understand that yet. I go to the architect with my idea, and they create a concrete plan. Do I already get a cost estimate at that point? Let’s say only a rough one, then they contract the trades and realize, oh, everything actually costs twice as much?! Of course, that wouldn’t be a good architect if they miscalculate that badly, but the risk is there. I understand that you can’t fix all prices 100% beforehand, but most of the costs should be known BEFORE you sign any contract. I don’t want to pay double later than I expected... Why is an architect not allowed to offer fixed prices? They must present some reasonable estimate before construction starts.How is an architect supposed to offer fixed prices? They don’t employ the contractors themselves or supply materials...
At the beginning, there is often a rough cost estimate based simply on square meters—meaning the architect may tell you, from experience, something like 1300€ per m² (5.4 ft²) of living space and 800€ per m² (8.6 ft²) for basement area. You can discuss with the architect what kind of standard fittings or materials they usually plan for, and you get a rough price...
Once you sign a contract with the architect, the planning becomes more detailed. The architect then prepares a more precise cost calculation based on the actual planned finishes, materials, etc.
With this detailed plan, the individual trades are then put out to tender… Whether the prices stay within the architect’s budget depends on their experience and so on…but they won’t guarantee it!
Der Da schrieb:
PS. you can’t hear my office PC Passive cooling in a fanless PC?
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