ᐅ Request for Evaluation of Heating and Ventilation Concept for a New Single-Family House

Created on: 31 Dec 2015 19:32
H
holg182
Hello everyone,

We are planning to build a detached single-family house, about 160 sqm (1,722 sq ft), on an 1100 sqm (11,840 sq ft) plot at the edge of town with a slight slope on slate soil. We are aiming for approximately a KfW 70 energy efficiency level, although with the current interest rates we are not relying on the related subsidies. Overall, our planning is going quite well, but when it comes to heating and ventilation, we are unsure if our plan really makes sense. Therefore, we appreciate your opinions on this 🙂

In general, we want to build and operate the house simply and cost-effectively, and it would be great if we could do this with a clear conscience for the environment. Our idea:

- A fairly well-insulated building envelope (see above), without it becoming a bottomless pit.
- Air-to-water heat pump
- Pellet stove in the living room
- Controlled mechanical ventilation (with heat recovery)
- Underfloor heating

The idea is that the air-to-water heat pump supplies most of the heat for the house, and the pellet stove in the living room provides extra support when it gets very cold outside. Ideally, this would happen automatically—so that the pellet stove switches on as soon as the outside temperature drops to a certain value, e.g., -3°C (27°F).

Here are a few questions for you experts:

1. Does this concept make sense as a whole?
2. Or would it be better / simpler / more cost-effective overall to use gas for purchase, operation, and maintenance?
3. Should the pellet stove in our setup be water-bearing (hydronic) or not?
4. Should the controlled mechanical ventilation system include heat recovery, or is that not necessarily required? Does a central or decentralized system make more sense here?
5. How can I find someone who can plan, recommend, offer, and install the right equipment for this setup (and not just the products that provide them with the highest commission)?

Thank you very much for your opinions—and Happy New Year in advance 🙂
S
saboj
3 Jan 2016 14:20
Using pellet bags was the key breakthrough for me in terms of energy consumption and heating technology. Previously, with self-service, the consumption matched the built standard.
L
Legurit
3 Jan 2016 14:27
That doesn’t make much physical sense, sorry... your house has a specific heat loss that you need to compensate for -.- whether you burn cucumbers or pellets, it stays the same.
Of course, if you put 200 kg (440 lbs) of wood in the stove and then open the windows wide because it’s too warm, or if you stay around at 24°C (75°F) for two days, that might change things.
However, I think this speaks less in favor of pellets or wood, and more for heat pumps or condensing boilers.
S
saboj
3 Jan 2016 14:53
That’s the great thing about it.
Heating concept is economical and pays off quickly.
No more ventilation concept needed because the relative humidity is now like in the desert. Heating can be enjoyable again.
You get used to strongly fluctuating room temperatures very quickly when everything heats up again in no time.

Yes, there was already some promotion for heat pumps and condensing boilers mentioned earlier.
L
Legurit
3 Jan 2016 15:00
I give up...
S
saboj
3 Jan 2016 15:26
It's still too early! 🙄
But be patient, this heating technology is yet to come.
At the moment, it still challenges the energy saving regulations and existing standards. Large-scale trials have been successfully underway for several years in many public, uninsulated buildings.
N
nordanney
3 Jan 2016 15:45
saboj schrieb:
That's the great thing about it.
Heating system is efficient and pays off quickly.
No longer any ventilation system needed, because the relative humidity is now like in the desert. Heating can be enjoyable again.
You get used to strong temperature fluctuations in the rooms very quickly, especially when everything warms up fast again.

Yes, there were also advertisements for heat pumps and condensing boilers further up.

???
Sounds like nonsense!