Renovation costs

But what I actually hoped for with this thread: Imagine you were renovating a house. You have free choice regarding money, location, and technology. What energy-saving measures would you take now and why? And which heating technology?

- Definitely insulate the floor – brings a lot, especially with underfloor heating, and you’ll never want to tear it up again later. Insulating from below is also good, e.g. basement ceiling.
- Underfloor heating – likewise. You won’t want to access it later, and if the heating needs to be replaced anyway, then make it really comfortable.
- Heating: I hate gas, so we chose pellets. Why do I hate gas? Where I lived before, houses occasionally exploded because of gas (Bremen), which I experienced firsthand. Secondly, it is a fossil energy source, so it has no future (even though there are still some reserves, but they are finite, plus dependence on Russian deliveries – no!). Thirdly, gas is the energy source of choice for cheap social housing, where I’ve spent most of my life, and these boilers are terribly loud when they start, shut off when you don’t need them – e.g. only ice-cold water in the middle of a shower... Cooking with gas might be trendy for top chefs, but lighting the stove with a match for me borders on caveman behavior. So you can tell, I’m not enthusiastic about gas, no matter how often my in-laws tell me everything would be different with modern gas boilers.
But everyone has to decide for themselves!
Gas condensing boilers are said to be very efficient and also well suited for low-temperature heating and can modulate well...

With pellets, you can also use a water-bearing pellet stove, which looks nice, gives you a flame view and "stove feeling," and also runs the underfloor heating on the side. They are very affordable around 3500 euros, and the installation is simple and cheap because all the technology including pumps and controls is built into the stove. We have a pellet boiler, which is a mix between a stove (regarding connections) and a boiler (no viewing window); it qualified for a higher BAFA subsidy than a stove, but the price was the same (Red compact slim for those who want to google it).

I would definitely have the windows and the front door replaced and also insulate the facade and attic. So everything that makes a mess, where you have to tear something up and where the savings potential is greatest, do it right at the start.

It’s best to have an energy consultant walk through the house and create a plan; it costs just a "few euros" – for which you can get a subsidy from KFW. He can also tell you how much insulation is needed where and what is most worthwhile.

If possible, I would also build a photovoltaic system on the roof. We did that first thing in 2013 and don’t regret it for a minute!

It’s best if you have an energy consultant go through the house and create a concept; that only costs a "few euros" – but you can get a subsidy from the KFW for that. He can also say how much insulation is needed where and what is most worthwhile.

Yes, we will definitely do that. As mentioned, on Thursday we will go through the place with an all-round craftsman and a construction engineer (separately) and see how they assess the situation. The construction engineer also said that he would like to do this in connection with an energy consultant, partly because that would make subsidies from the government side possible.

We don’t have a direct problem with gas now. I definitely won’t be using a Brötje boiler (the Brötje constantly fails in our rental apartment), but other than that I’m happy to be advised on what is sensible and financially feasible.

If you involve an energy consultant, make sure that he is on the dena list. They have a website where there is an energy consultant search engine.

Thanks for the tip. This is exactly what I'm here for. :-)

So, almost all abbreviations understood... ;-)

Great! You’re getting into the topic. I’m glad.

Actually, everyone in our circle of acquaintances advised us against underfloor heating, as well as wall heating (WH?). Too slow, too finicky. Does a mix of underfloor heating/WH and conventional radiators make sense?

My Steffi and I don’t like underfloor heating, so we don’t have it. Of course, it’s basically standard nowadays. Everyone wants it, except for 2 people in Germany, one is writing here. I’m ashamed, but don’t want any further comments on that. :eek:
Like every system, underfloor heating has pros and cons. Everyone should decide for themselves.

A mix of underfloor heating / radiators can make sense. For example, if the household wants underfloor heating in the bathroom but not elsewhere. I almost did that, but the 4-week extension of the construction period stopped me back then, I had water up to my lower lip at that time.
It works without problems, probably even with the aforementioned Vitogas-200.

In the cellar of the house there is a gas boiler (Vitogas 200), I assume it is included in the purchase price and could be used. Is something like that worthwhile? Or sell it off and invest in something future-proof?

Sure, the heating system belongs to the house.
That is a low-temperature heating boiler, not a condensing boiler. Has about 90% - 93% efficiency. But it’s not exactly a disaster.
How old is the device?
Is it still okay, what does the chimney sweep say?
If it’s still fine and you stick with gas heating: leave it in for now, replace later. That would be my advice.

I’ve also heard a lot of negative things about controlled residential ventilation from traditionalists – "Then you can’t open windows in winter anymore" – "not good because prone to malfunctions" – etc. Someone here must have a different opinion, right?

Crystal clear. The claim above is pure nonsense.
The truth is: You don’t have to open windows in winter to ventilate. Of course, you may still do so. Doesn’t hurt. Nothing breaks, except wasted energy when ventilating by opening windows.
Controlled residential ventilation with heat recovery is great.

I’ll first take the other stories as input and bring them into the conversation the day after tomorrow. My main concern would be to get a lot of light into the house. Old building, small windows (except for one 3.50 x 1.50 window...), little light. I’d like to install large roof windows or sensibly create space and light with dormers. Of course, in the end it’s a matter of cost again...

Double casement windows are still okay price-wise. And relatively easy to do, but they have comparatively poor insulation...
But dormers. Oh oh oh! Dormers are always expensive. Very expensive. Rough estimate: No matter how small the dormer is, about 10,000 Euros are gone...

As for the bathroom, as I said, I’m not very demanding. I really like shower niches with proper tiling, that would be two small drywall walls. Simple tub and a simple toilet, done. I hope we can manage with little money there... Let’s see what the lady of the possibly future house says about that... ;-)

I’m curious.

Thirdly, gas is the energy source of choice for cheap social housing, where I had spent my life so far, and these boilers are horribly loud when they turn on, turn off when you don’t need them – e.g. only ice-cold water right in the middle of showering...).

;)
A modern gas condensing boiler has a water tank connected.

Such a flow-through gas heater device, which you mean, is actually rarely encountered and really loud. Although: These things also exist in modern versions, they work too. We have such a thing in the house that my father lives in and that I own 50% of: terrible contraption.

The origin of the so-called fossil energy sources is controversial, especially in Russian research, and the views are changing, also due to extraterrestrial research and the presence of methane on other planets. And just yesterday I saw another report about it. Very interesting. We can talk via PM, obviously off-topic and probably not of interest to the OP. The fact is that these energy sources release CO2, which is not beneficial for the environment.

The fact is: the electricity for this heat pump mainly comes from good coal power plants in winter... very resource-conserving in "". You have pellets – that’s great. We also heat a bit with wood/fireplace stove. I think that’s okay.

By the way, one can endlessly argue about the philosophy of heating and its energy source. The right/perfect solution doesn’t yet exist, in my opinion, as of the year 2016.........

Best regards
Thorsten