ᐅ Vestaxx window heating – experiences?

and a few more arguments:
Shower partitions (the glass panels known from walk-in showers) which then serve as surface heaters instead of towel radiators, possibly with an integrated towel rail.

Basement windows that provide a low-level base heating, instead of installing radiators or underfloor heating for storage areas and secondary rooms.

Garage windows with the same effect. Being able to heat (warm up) a garage with minimal effort when needed would be a real advantage.

Sauna windows for preheating??

Stairwell windows, if the design specifies a warm stairwell?

All installation locations where this type of heating could offer advantages over traditional methods.

Best regards, christian

After 15 pages of "discussion," the key questions (future electricity prices, CO2 emissions, how much of the heating electricity can be covered by photovoltaics, etc.) are still unresolved. Repeating the same long texts doesn’t really help us move forward.

If you really want to help homebuilders, try providing a precise and clear comparison between heating systems (just to avoid misunderstandings: photovoltaics are not a heating system).

I am also genuinely interested in how much CO2 is generated by installing a hydronic underfloor heating system. If you don’t have the information, just say so, and please don’t claim it’s way too much or imply that everyone can just calculate it themselves.

I can only estimate here, but I assume that the few pipes will balance out the saved energy consumption.

and then:

Windbreak balcony, creating a cozy corner and allowing the outdoor heater to be removed.

Skylights as cold air barriers

Everything can of course be activated as needed, but it would definitely be an interesting feature.

Roof windows for later attic conversion. Who wants to search for the supply and return pipes in the floor below?

Conservatories, where retrofitting heating is also a major issue.

But, what do I know?

11ant schrieb:

The contract value is so much lower that it worries the supplier more than the avoided mess pleases the client, but not the supplier.
We are talking about a hypothetical replacement of the glazing in 30 years—who can say today what the conditions will be then—is this discussion really useful? I don’t think so! Let’s focus on the here and now.

But not on such a specific topic; this tends to lead to thousands of off-topic posts rather than a meaningful conclusion.

I understand that argument! That’s why I only wanted to outline what our system includes and why we believe this is a relevant topic for people who need to decide on a heating system for their new build right now. I aimed to provide information that is understandable—no, better—verifiable by calculation. However, because of—how can I put it politely—preconceived opinions, “etc.,” I often find myself only on the defensive. If someone is looking here for people with experience in electric wall heaters, they won’t find any. But we do—we have equipped about 150 new builds with it, and there are multi-year user experiences and, of course, consumption data available. If someone is genuinely interested in speaking with one of the users or visiting them, I would be happy to help arrange that.

Christian 65 schrieb:


The functionality and consumption have probably been explained sufficiently. The approach of considering all costs, meaning both consumption and initial investment, actually makes sense to some extent.

However, I would like to add the following:
If you go to a Porsche forum, a major topic is the actual fuel consumption of the new models. Someone buys a very expensive car and then discusses the actual fuel consumption.

What does that tell me? The upfront costs as a one-time investment are planned and paid for in the budget. Once that’s done, it’s quickly settled, otherwise, it’s not even considered.

The consumption costs as ongoing expenses, however, are open to discussion. You might think: just buy a cheaper car, and then the fuel prices over the next 10 years won’t matter much.

But that’s not how people think. And here lies the first point of criticism.

Alright, where would I see an approach? In my humble opinion, even more positive aspects should be created to achieve broader acceptance.

For example, one idea could be to integrate an intelligent outer glass pane that, when a control voltage is applied, varies its light transmittance up to opacity (possibly complete darkening).

The electrical installation for the window heating must be routed to the frame anyway, so a synergy effect could be created here. And if, through this, I could also do without electric shutters with all their weaknesses, that would be a new line of thought.

That means: no more shutter boxes, which nowadays are almost as expensive as the windows.
The possibility to anchor wide elements into the ceiling or lintel.
One less thermal bridge, and all the omitted special measures required for monolithic construction.
No space problems caused by ring anchors running above.
The window position within the masonry cross-section can be freely chosen.
And a few more reasons to avoid shutter boxes.

Marketing this as a comprehensive new option might just work.

Best regards, Christian

Hello Christian – first of all, thank you for your comments and suggestions – now it’s fun again here 😉

Regarding the topic … “buy a cheap car and then fuel costs don’t matter” … that’s a bit too simplistic. It’s better to say: buy a low-maintenance, affordable car with innovative technology, which might consume three times as much fuel as the expensive car. Then use the money saved to buy a “fuel station” (photovoltaic system) that provides you with three times as much free fuel and can even charge other cars. Everyone can decide for themselves, and that’s a good thing.

Outer glass for darkening
This already exists – but unfortunately, one of the players (E-Control) filed for insolvency last year due to faulty control. Also, the technology is far too expensive (€1,000/m² (about $1,070 per sq yd)) and currently not competitive compared to external sunshades.

Electric shutters
This is up to the customers – some choose them, others do not. Shutters do not interfere with window heating. Synergies are even used here, since shutters need power supply, and the electrician can lay a five-core cable at the same time. We do not provide advice pro or contra shutters – that’s outside our scope. But your described advantages are certainly helpful.

Vestaxx GmbH schrieb:

I’m just saying 500,000 heat pumps per year 😱 😱 😱 – who is going to build all of those (lead times: currently months or even years) and WHO will install them all??? Haven’t you heard the news???

I’m less worried about production. With consistently high demand, there will be enough companies to manufacture heat pumps. As a business, you should know the concept that demand will be met 😉

And please, let’s have an honest calculation without photovoltaics. For example, I can only fit 15 kWp on my roof if I also cover the north side. With a roof size of 9 x 10 m (30 x 33 ft) plus eaves minus side clearances, you can realistically expect about 50 m² (540 sq ft) or 10 kWp per side. Surely you have noticed that most new buildings today have photovoltaics installed alongside heat pumps, because it makes financial sense. I also find it unfortunate that you didn’t address the topic of infrared heating on walls versus infrared heating on windows more thoroughly. In that discussion, I can simply leave out photovoltaics, heat pumps, and all the other noise.

I ran the numbers in my head: building envelope equivalent to Efficiency House 40 (actually 40+ and thus already includes photovoltaics, which we’ll exclude here). Open-plan area with 2 panels, bedroom, children’s room, 2 offices, and 2 bathrooms with one panel each. That makes 8 panels. Assuming €250 (~$270) each (which seems quite generous for the faster option), that’s €2,000 (~$2,150) total, and I can install them in under 2 hours. Now your system: €10,000 (~$10,700), so 5 times as expensive. I can place the panels fairly freely and, if necessary, mount them on the ceiling, but the windows are fixed. What about the bathroom? There I only have small windows—would something with a surface temperature of 40°C (104°F) still provide sufficient warmth? What about the shower behind the masonry partition?