Hello,
after nearly a year of discussions with various companies and thorough research on prefabricated houses and solid construction, we decided on solid construction. Fortunately, we inherited the plot of land.
We now have a clear idea of what our dream home should look like (at least visually, which inspired our drawings):
- House type: urban villa
- Size: approx. 140 m² (1507 sq ft)
- many and especially large windows, corner glazing
- a system for controlled ventilation with heat recovery
With each conversation, we were able to narrow down the providers, and things are getting serious :-) We have an offer from a developer that suits us. He seems reliable, we’ve only heard good things about the company so far, the concept appears coherent, and the preliminary designs look good.
He has now provided us with an offer that basically includes all the work. The house will be delivered turnkey. Only the utility connections, insurance, and government fees will be added. Since we are very busy professionally, we deliberately decided against doing any work ourselves.
From the start, we set a budget limit of around 200,000 (with utility connections and additional costs, we expect to end up around 220,000).
We’ve heard about the KfW 70 (or even higher) standards... The developer calculated everything for us, and we ended up with the following options:
Offer 1:
KfW 70 standard including underfloor heating, air-to-water heat pump, controlled ventilation with heat recovery, fireplace connection
=> 230,000
Offer 2:
No KfW 70 standard, standard energy-saving regulation 2009, underfloor heating, controlled ventilation with heat recovery, fireplace connection, gas condensing boiler
=> 200,000
Offer 3:
No KfW 70 standard, standard energy-saving regulation 2009, underfloor heating, controlled ventilation with heat recovery, fireplace connection, air-to-water heat pump
=> 210,000
At first, we were attracted by the good conditions of the KfW 70 standard, but we realized that the interest rates are not much better than the current market. So, the subsidies would only save us around 5,000 EUR over the years. The additional investment for KfW 70 is significantly higher... No one can say exactly how much you save annually with KfW 70 compared to the 2009 energy-saving regulation. We have also been skeptical about solar systems so far, since they usually only pay off after many, many years (if at all).
I wanted to ask which option you would personally favor or what else we should consider!?
I appreciate any tips or advice.
Best regards,
Tim
after nearly a year of discussions with various companies and thorough research on prefabricated houses and solid construction, we decided on solid construction. Fortunately, we inherited the plot of land.
We now have a clear idea of what our dream home should look like (at least visually, which inspired our drawings):
- House type: urban villa
- Size: approx. 140 m² (1507 sq ft)
- many and especially large windows, corner glazing
- a system for controlled ventilation with heat recovery
With each conversation, we were able to narrow down the providers, and things are getting serious :-) We have an offer from a developer that suits us. He seems reliable, we’ve only heard good things about the company so far, the concept appears coherent, and the preliminary designs look good.
He has now provided us with an offer that basically includes all the work. The house will be delivered turnkey. Only the utility connections, insurance, and government fees will be added. Since we are very busy professionally, we deliberately decided against doing any work ourselves.
From the start, we set a budget limit of around 200,000 (with utility connections and additional costs, we expect to end up around 220,000).
We’ve heard about the KfW 70 (or even higher) standards... The developer calculated everything for us, and we ended up with the following options:
Offer 1:
KfW 70 standard including underfloor heating, air-to-water heat pump, controlled ventilation with heat recovery, fireplace connection
=> 230,000
Offer 2:
No KfW 70 standard, standard energy-saving regulation 2009, underfloor heating, controlled ventilation with heat recovery, fireplace connection, gas condensing boiler
=> 200,000
Offer 3:
No KfW 70 standard, standard energy-saving regulation 2009, underfloor heating, controlled ventilation with heat recovery, fireplace connection, air-to-water heat pump
=> 210,000
At first, we were attracted by the good conditions of the KfW 70 standard, but we realized that the interest rates are not much better than the current market. So, the subsidies would only save us around 5,000 EUR over the years. The additional investment for KfW 70 is significantly higher... No one can say exactly how much you save annually with KfW 70 compared to the 2009 energy-saving regulation. We have also been skeptical about solar systems so far, since they usually only pay off after many, many years (if at all).
I wanted to ask which option you would personally favor or what else we should consider!?
I appreciate any tips or advice.
Best regards,
Tim
One more addition, since I can’t edit anymore:
- Exterior walls: 36.5cm (Poroton T9)
- Interior walls: 11.5cm (11cm WLG040)
In my opinion, the only thing missing for a KfW70 standard would be the additional insulation under the slab and the ground source heat pump?
Best regards,
Tim
- Exterior walls: 36.5cm (Poroton T9)
- Interior walls: 11.5cm (11cm WLG040)
In my opinion, the only thing missing for a KfW70 standard would be the additional insulation under the slab and the ground source heat pump?
Best regards,
Tim
H
Häuslebauer4013 Oct 2011 06:10What is not included in the offer:
- Landscaping
- Garages
- Fireplace (only the connection and a two-flue chimney)
- Entrance platform
- Site development and fees for authorities What is the condition of the ground? Is there already a soil survey report? Based on this, is additional soil excavation required and what are the disposal costs? What about additional costs from a deeper frost protection layer? (The house price usually includes only 15 - 25 cm (6 - 10 inches), which is often insufficient).
What about the wastewater pipe, handover/inspection chamber, and the connection to the main line? Rainwater pipe and connection, possibly a cistern?
All these are quite costly items and these are just the points that come to mind offhand. You should check whether and to what extent all these points are included in the price according to the building contract/planning permission or not.
B
Bauexperte13 Oct 2011 11:39Hello Tim,
Utility room sounds plausible, a purely mechanical ventilation system with heat recovery does not require much space; I cannot assess the extra cost for attic insulation, as it depends on factors like the roof shape, height to ridge/attic size, whether the standard staircase leads to the attic, etc. When installing such systems in the attic, you should think ahead—what happens if the system needs to be replaced at some point?
Yes and no 🙂 I mentioned two different systems. Tecalor TVZ refers to the controlled ventilation system with heat recovery—costs roughly 9,000 EUR (9,000 USD). The combined unit is called Tecalor THZ 303 integral, with or without the “SOL” option—costs around 10,000 EUR (10,000 USD) without solar, or about 13,000 EUR (13,000 USD) with solar. The combined device integrates the air-to-water heat pump, controlled ventilation with heat recovery, and optionally a solar system. If I remember correctly, Buderus offers comparable technology at similar prices; since we rarely work with Buderus, I don’t have their model numbers handy.
If you opt for the controlled ventilation with heat recovery plus a separate air-to-water heat pump, costs will be about 14,000 EUR (14,000 USD). If you choose the combined unit from the start, it will cost either about 10,000 EUR (10,000 USD) without solar or 13,000 EUR (13,000 USD) with solar. Note that the integral unit requires quite a bit of space; it projects roughly 80 cm (31 inches) from the wall into the room and needs supply and exhaust air connections within about 3.5 m (11 feet).
The building envelope as a whole—including triple glazing and roof construction—forms the basic requirement for KfW 70. Only when renewable energy systems are added, assuming all components are properly coordinated, does it become a certified KfW 70 efficiency house.
Insulation under the slab is usually only necessary for a solidly built single-family home if you choose a gas condensing boiler combined with solar and controlled ventilation. With these two systems and a detached building, meeting the KfW certification can often be quite tight.
I have already explained to you that your estimated additional costs won’t be sufficient. Since you are looking for decision support, I suggest having your preferred provider’s documents reviewed externally and independently. In this context, you might also consider external construction supervision. We can only provide partial answers here because we do not have the same access to your documents as you do. Therefore, all answers—including mine—are fragmentary and without guarantee. 😉
** All prices I mentioned are additional costs—the usually included gas condensing boiler and solar system have been deducted.
Best regards
TimB schrieb:
From what I read, the provider told us that the ventilation system will be installed in the utility room (about 8 sqm (86 sq ft)). It can also be installed in the attic, but then the attic would need better insulation, which would add around 3500 EUR (about 3500 USD) extra cost (currently only insulation according to the 2009 Energy Saving Ordinance).
Utility room sounds plausible, a purely mechanical ventilation system with heat recovery does not require much space; I cannot assess the extra cost for attic insulation, as it depends on factors like the roof shape, height to ridge/attic size, whether the standard staircase leads to the attic, etc. When installing such systems in the attic, you should think ahead—what happens if the system needs to be replaced at some point?
TimB schrieb:
Does that mean that if I add a solar system to the ventilation, the extra cost is only a relatively "small" amount of about 3000 EUR (about 3000 USD)? I always thought this cost would be much higher...
Yes and no 🙂 I mentioned two different systems. Tecalor TVZ refers to the controlled ventilation system with heat recovery—costs roughly 9,000 EUR (9,000 USD). The combined unit is called Tecalor THZ 303 integral, with or without the “SOL” option—costs around 10,000 EUR (10,000 USD) without solar, or about 13,000 EUR (13,000 USD) with solar. The combined device integrates the air-to-water heat pump, controlled ventilation with heat recovery, and optionally a solar system. If I remember correctly, Buderus offers comparable technology at similar prices; since we rarely work with Buderus, I don’t have their model numbers handy.
If you opt for the controlled ventilation with heat recovery plus a separate air-to-water heat pump, costs will be about 14,000 EUR (14,000 USD). If you choose the combined unit from the start, it will cost either about 10,000 EUR (10,000 USD) without solar or 13,000 EUR (13,000 USD) with solar. Note that the integral unit requires quite a bit of space; it projects roughly 80 cm (31 inches) from the wall into the room and needs supply and exhaust air connections within about 3.5 m (11 feet).
TimB schrieb:
One more note, since I can’t edit anymore:
- Exterior walls: 36.5 cm (14 inches) Poroton T9
- Interior walls: 11.5 cm (4.5 inches) 11 cm WLG040
The only thing missing for a KfW 70 standard, in my opinion, would be extra insulation under the slab and the air-to-water heat pump?
The building envelope as a whole—including triple glazing and roof construction—forms the basic requirement for KfW 70. Only when renewable energy systems are added, assuming all components are properly coordinated, does it become a certified KfW 70 efficiency house.
Insulation under the slab is usually only necessary for a solidly built single-family home if you choose a gas condensing boiler combined with solar and controlled ventilation. With these two systems and a detached building, meeting the KfW certification can often be quite tight.
I have already explained to you that your estimated additional costs won’t be sufficient. Since you are looking for decision support, I suggest having your preferred provider’s documents reviewed externally and independently. In this context, you might also consider external construction supervision. We can only provide partial answers here because we do not have the same access to your documents as you do. Therefore, all answers—including mine—are fragmentary and without guarantee. 😉
** All prices I mentioned are additional costs—the usually included gas condensing boiler and solar system have been deducted.
Best regards
Similar topics