ᐅ Using a Ventilated Facade as a Supplemental Heating Source?

Hello everyone,

I have had an idea in mind for weeks.
The house faces south, so I looked into air collectors. However, I wouldn’t want to attach those black units directly to my yellow facade. The facade is only plastered, not insulated; made of 36cm (14 inch) hollow concrete blocks from the former GDR.
So now I’m considering insulating the facade externally with wood fiber insulation and then mounting black or dark trapezoidal metal sheets at a distance of 10cm (4 inches) from it. The air heated in the gap would be blown down through an air duct into a room. The incoming air would come from the same room, so only the circulated air is heated. The metal panels would be sealed on all outer sides to prevent any warm air from escaping.

Since there are four rooms along the front of the house, it would be possible to heat either all four or just two rooms with this system.

Could this work? Would it actually provide any benefit? The area involved would be about 30–35 sqm (320–375 sq ft).
Would it work even with solar radiation and some wind? Or would the wind blow the heat away immediately?
It is mainly intended to support the heating during the transitional seasons.

Best regards,
Sebastian

Interesting idea. However, warm air rises upwards. The blower also requires electricity.
The investment and operating costs will likely far exceed the heating savings.
This setup will probably only work within a narrow temperature and weather range.
A ventilated facade is intended for insulation, not for heating.
In summer, it will become extremely hot behind your black metal cladding. Insulation won’t help in the long run, and your house will heat up.
At that point, you might want to consider air conditioning...
So overall, it seems rather impractical.

Alright, thanks for the quick response. The fan should run on a small solar panel. So completely self-sufficient and off the main power grid.

In the Allgäu region, a hay drying system operates based on this principle, supplemented by a wood chip heating system. There is a report about it on YouTube (Heutrocknung Berghof Babel). Here you can take a look at the principle, and manufacturers are also mentioned. Whether this makes sense for a residential building, I do not know.

The principle generally works. However, simply attaching metal sheets to the facade does not.

Take a look at the bio-solar house based on the house-in-house concept. They build houses exactly following the approach you have in mind. The basis is, on one hand, the warming of air in the cavity behind the ventilated facade, and on the other hand, the heating through an otherwise unheated winter garden with a large glass area.

This system can also be retrofitted as part of a renovation, but the effort involved is significant.

In summer, the house does not overheat because ventilation openings at the eaves or gable side release warm air when outside temperatures rise.

You can take this concept even further with a house inside a greenhouse or with a fully integrated double facade including the roof. There are some interesting videos about both on YouTube.

That’s true, I’ve seen that greenhouse concept on TV before. Basically, they live in a greenhouse that regulates its own climate. But for me, it’s a bit too open… then the neighbors can always see a lot ;-)

First of all, thanks for the kind responses. Let’s see if and what I will do in that direction.
The current green government is pushing everything at the moment, but without thinking it through, and then changes its mind again. What is right and great today is already wrong tomorrow and has to be replaced. In terms of heating technology, I’ll just wait out the situation with my oil boiler and keep repairing the thing until it finally breaks down.