Combination of ventilation system and solar system for domestic water?

Hello,

If I were you, I wouldn't be so hasty; I'm already looking forward to your post on the topic once the final invoice is available

Rhenish greetings

Hello Bauexperte,

why??
I have no exact idea what a solar thermal system costs, but estimated I would place the whole thing in the range of 5 thousand euros. Is that about right?
You’re not going to tell me now that the material costs for 4 cm insulation are 5 thousand euros?! - That would mean the 20 cm insulation, which I would have had anyway, would have cost 25 thousand euros?! Just for the material! I can’t imagine that...

As I said - there is no difference in installation / labor costs / time whether you install 20 or 24 cm. So the net difference is really only the material price.

Next time I'm at the hardware store, I'll take a look at the prices for insulation

Greetings from the Ruhr area
Micha

@Micha&Dany

You cannot simply say that 4cm more in the roof will be enough and that’s it. Depending on the house, various other measures may need to be taken. It depends on how it is already planned. If the entire insulation was already cut very tight, then it will not be enough to just increase the roof insulation by 20%. The house does not consist of just the roof. And even with a pure extension of the roof insulation, more costs can arise than just the difference between 20 and 24 insulation. For example, if you have 20 cm cavity insulation and want to increase it to 24, but the rafters are only 20 cm in size, you additionally need 4 cm of insulation below the rafters, including counter battens, extra work, etc. And if the whole change is only made after signing with a general contractor/contractor/developer, then it costs whatever price the contract partner decides.
A lot of things can influence this. So to say flat out that it will be a few thousand euros cheaper if you omit the solar thermal system is, in my opinion, irresponsible...

Hello,

although it no longer fits the original topic of underfloor heating/radiators, nonetheless.

They are two completely different things being "dealt with" here.
Insulation reduces heating energy demand, solar thermal system more or less reliably substitutes consumption (mostly hot water or hot water/heating (HU)).
To even compare the investments for each, demand and consumption must be determined.
The solar thermal system has, among other things, the disadvantage that the paper form and actual results sometimes differ significantly. The causes for this are diverse. In addition, control, pump, hydraulics, etc. are required.
Those who are content with the paper specifications of the solar thermal system are advised to use a heat meter to compare the actual yield with the vendor’s performance forecast.

v.g.

Hello Micha,

why??
I have no exact idea what a solar thermal system costs, but I would estimate the whole thing to be around 5 thousand euros. Is that about right?

I would be surprised; I’m thinking more along the lines of 3.5-3.7 thousand euros.

You’re not seriously telling me that the material costs for 4 cm insulation amount to 5 thousand euros?!

As "Der Bjoern" correctly writes, it’s not "just" the increase of 4 cm insulation; to comply with the 15% rule there is a bit more involved. However, I won’t speculate here since I don’t know your contracts or the planned execution. I only advised caution against premature excitement because I have all too often witnessed that the joy was dampened by the resulting presented figures. Especially when it came to reimbursements after contract conclusion.

If in the end there is more money in the pot, great – let us know.

Rhenish greetings