ᐅ Energy Saving Regulation 2016 or KfW 55 Standard for a Bungalow with Air-to-Water Heat Pump and Controlled Mechanical Ventilation, Optional Photovoltaic System
Created on: 5 Jun 2019 08:25
M
micric3
Good morning,
We are currently in the preliminary planning phase and are being flooded with information from various builders.
The topic of the "Energy Saving Ordinance 2016 or KfW 55 standard" especially leads to additional discussions.
The current concept for a household of four is as follows:
- Underfloor heating + air-to-water heat pump / controlled mechanical ventilation system combo, for example Vaillant recoCOMPACT (alternative: Nibe 730/750)
- Photovoltaic system ready for later retrofitting
- No gas connection possible/available
Opinions from some builders:
- KfW 55 was only attractive because of the low interest rates compared to traditional bank loans
- Currently, few are building to KfW 55 standard; the Energy Saving Ordinance 2016 is 'back in trend'
Calculation from another builder:
30 cm (12 inches) exterior masonry instead of 24 cm (9.5 inches) exterior masonry (both according to Energy Saving Ordinance 2016) = (costs €3,750)
(Additional costs for KfW 55 with 36.5 cm (14 inches) exterior masonry, floor slab insulation, increased roof insulation, and KfW 55 calculations and documentation were (costs €14,680))
I would like to hear some opinions on this:
Good luck
Michael
We are currently in the preliminary planning phase and are being flooded with information from various builders.
The topic of the "Energy Saving Ordinance 2016 or KfW 55 standard" especially leads to additional discussions.
The current concept for a household of four is as follows:
- Underfloor heating + air-to-water heat pump / controlled mechanical ventilation system combo, for example Vaillant recoCOMPACT (alternative: Nibe 730/750)
- Photovoltaic system ready for later retrofitting
- No gas connection possible/available
Opinions from some builders:
- KfW 55 was only attractive because of the low interest rates compared to traditional bank loans
- Currently, few are building to KfW 55 standard; the Energy Saving Ordinance 2016 is 'back in trend'
Calculation from another builder:
30 cm (12 inches) exterior masonry instead of 24 cm (9.5 inches) exterior masonry (both according to Energy Saving Ordinance 2016) = (costs €3,750)
(Additional costs for KfW 55 with 36.5 cm (14 inches) exterior masonry, floor slab insulation, increased roof insulation, and KfW 55 calculations and documentation were (costs €14,680))
I would like to hear some opinions on this:
Good luck
Michael
B
boxandroof5 Jun 2019 15:32nichts zu schwör schrieb:
Basically, the planner should point out the issue of depreciation, since in about 1–2 years the Passive House standard will be required by the energy saving regulations. The depreciation is likely to be minimal, as almost no buyers are familiar with this, and even fewer base their decisions on minor differences in insulation. In practice, what matters more for ongoing costs is whether the heating system is properly designed and operated. You can see the results—also when selling—in the energy performance certificate; some buildings perform better there than certain Passive Houses.
nichts zu schwör schrieb:
The question is just how the house is verified, meaning how good the building envelope really is. That is, without a high primary energy factor like with electricity or even with photovoltaics. The H’t value provides information about the quality of the building envelope.
micric3 schrieb:
Aerated concrete is at least according to the offer
@fragg: I didn’t find it quickly from Vaillant, but the Nibe F730 has exactly this exhaust air heat pump, why should it be worse than an outdoor air system? The system is basically the same The easiest thing for everyone involved is to simply accept as a given "no exhaust air heat pump in a non-passive house."
I will meet with customer service for a consultation.
Exhaust air heat pumps with central exhaust and decentralized supply air
This solution uses the slight negative pressure in the apartment caused by the system. This ensures that fresh air flows in through exterior wall vents into the supply air areas. Warm indoor exhaust air is drawn from sensitive areas such as the kitchen, bathroom, or guest toilet through ventilation ducts to the heat pump. Before being discharged outside through a roof hood or ventilation wall grilles, most of the heat energy it contains is extracted. The exhaust air thus serves as a heat source for the integrated heat pump to produce hot water for heating and domestic use. Typically, these systems are designed as compact units with an integrated domestic hot water storage tank.
Exhaust air heat pumps with central exhaust and central supply air
These heat pumps operate on the same principle as the system described above; however, the supply air is preheated by the heat pump and delivered through ventilation ducts to supply air areas such as bedrooms, children’s rooms, or living rooms.
Air-to-water heat pump with crossflow heat exchanger <-- maybe this model here!?
Here, the exhaust air transfers most of its energy to the supply air via a cross counterflow heat exchanger before being vented outside and discharged. Depending on the heating demand, it still passes over the surface of the air-to-water heat pump evaporator, where it transfers residual heat to the refrigerant circuit of the heat pump. If additional energy is required for heating or domestic hot water preparation, it is obtained from the outside air supplied to the heat pump.
I will also review the consumption data from the online database, although unfortunately, it only covers 2018/2019.
Ultimately, the consensus seems to be that if you choose a heat pump, better insulation is also necessary. But without precise calculations, it appears to remain just a rough estimate.
Good luck
Michael
Exhaust air heat pumps with central exhaust and decentralized supply air
This solution uses the slight negative pressure in the apartment caused by the system. This ensures that fresh air flows in through exterior wall vents into the supply air areas. Warm indoor exhaust air is drawn from sensitive areas such as the kitchen, bathroom, or guest toilet through ventilation ducts to the heat pump. Before being discharged outside through a roof hood or ventilation wall grilles, most of the heat energy it contains is extracted. The exhaust air thus serves as a heat source for the integrated heat pump to produce hot water for heating and domestic use. Typically, these systems are designed as compact units with an integrated domestic hot water storage tank.
Exhaust air heat pumps with central exhaust and central supply air
These heat pumps operate on the same principle as the system described above; however, the supply air is preheated by the heat pump and delivered through ventilation ducts to supply air areas such as bedrooms, children’s rooms, or living rooms.
Air-to-water heat pump with crossflow heat exchanger <-- maybe this model here!?
Here, the exhaust air transfers most of its energy to the supply air via a cross counterflow heat exchanger before being vented outside and discharged. Depending on the heating demand, it still passes over the surface of the air-to-water heat pump evaporator, where it transfers residual heat to the refrigerant circuit of the heat pump. If additional energy is required for heating or domestic hot water preparation, it is obtained from the outside air supplied to the heat pump.
I will also review the consumption data from the online database, although unfortunately, it only covers 2018/2019.
Ultimately, the consensus seems to be that if you choose a heat pump, better insulation is also necessary. But without precise calculations, it appears to remain just a rough estimate.
Good luck
Michael
B
boxandroof5 Jun 2019 17:20micric3 schrieb:
In the end, the consensus seems to be: if you choose a heat pump, you should also improve the insulation. Better insulation increases the efficiency of the heat pump, but there is a point where adding more insulation becomes uneconomical. There are plenty of cases where an older building is heated economically with a heat pump. Buildings built to energy saving regulations are already reasonably well insulated. Adding mechanical ventilation with heat recovery and improving the insulation here and there (with or without government subsidies) will make the system work.
More important is the planning of the surface heating system and the overall hydraulics, as well as ensuring that no mistakes are made in the installation.
Zaba12 schrieb:
It always depends on the framework conditions: The cost factor for timber frame construction without a basement is minimal. Solid construction with bricks without external thermal insulation composite system (ETICS) but with a basement is a completely different matter to achieve KFW55 standards compared to the 2016 Energy Saving Regulation. I can’t really judge the timber frame part; we only have a standard cavity wall construction. That was enough for KFW55.
The situation is very individual, that’s true. In 2016, the KFW loans had such favorable conditions that we saved a lot on interest, and with the 5000€ grant combined, it was well worth it. However, since we only had about 10% equity, our interest rates weren’t the best.
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nix zu schwör9 Jun 2019 10:10@boxandroof
Precisely because a layperson cannot accurately assess depreciation, a planner may potentially be held liable. Ongoing costs are directly related to this.
A heat pump currently seems favorable mainly because the primary energy factor has been increased by political decision, which does not actually change the cost per kWh.
The Energy Saving Ordinance is not being replaced by the Building Energy Act after EnEV2019 without reason.
If it were truly a passive house from 2020/21 onwards, we would likely only be talking about an electric heating element in the ventilation system with heat recovery.
Improved insulation does not increase the efficiency of a heat pump, which is generally equally low for air-source heat pumps. An annual performance factor (COP) of at least 4.0 is an illusion.
VDI 4650 is not a practical evaluation method, which makes sense because otherwise, any manufacturer could calculate an annual performance factor however they wanted.
In addition to higher operating costs, the short service life of air-source heat pumps must be considered, with necessary reinvestments directly affecting the return on investment (ROI). (Assuming normal hot gas temperatures)
Precisely because a layperson cannot accurately assess depreciation, a planner may potentially be held liable. Ongoing costs are directly related to this.
A heat pump currently seems favorable mainly because the primary energy factor has been increased by political decision, which does not actually change the cost per kWh.
The Energy Saving Ordinance is not being replaced by the Building Energy Act after EnEV2019 without reason.
If it were truly a passive house from 2020/21 onwards, we would likely only be talking about an electric heating element in the ventilation system with heat recovery.
Improved insulation does not increase the efficiency of a heat pump, which is generally equally low for air-source heat pumps. An annual performance factor (COP) of at least 4.0 is an illusion.
VDI 4650 is not a practical evaluation method, which makes sense because otherwise, any manufacturer could calculate an annual performance factor however they wanted.
In addition to higher operating costs, the short service life of air-source heat pumps must be considered, with necessary reinvestments directly affecting the return on investment (ROI). (Assuming normal hot gas temperatures)
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