Sun exposure and shading, experiences

Hello,

we have triple-glazed windows and on the south side [Raffstores] and everywhere else [Rollläden].
Assuming the sun is blazing from the south.
The temperature on the north side is 36 degrees. The temperature inside the house is 24 degrees.
Does it make a difference how long it takes for the heat from the north side to enter the house, whether the [Rollläden] are up or down?
Would it make a difference whether [Rollläden] or [Raffstores] are installed there?

In winter, the slat position of the [Raffstores] is supposed to help allow more solar energy into the room.
How should the slats be positioned to utilize the most solar energy?
Or is it always best for solar gain if the [Raffstores] are fully up?

Best regards

Hello, we have triple-glazed windows and on the south side [Raffstores] and elsewhere roller shutters.

Are you already using it like this or are you still planning it? We have practically the same here with the house facing south/south-west, so in summer well supplied with sun at the entrance, utility room, guest room, guest bathroom on the north side). We have hardly any windows to the north and our few roller shutters there are almost never down, at most occasionally in the west in the guest room. Closed roller shutters on the north side probably won’t change much, since there is hardly any direct sun there for us. Whether it makes a difference I don’t know from personal experience, but I rather think not. However, we chose roller shutters there mainly for cost and especially darkening reasons. In general, I find [Raffstore] fantastic because you can adjust them individually. As I said, I have no measurements on this, but from experience I would always do it that way again; that would be one of my most important and safest decisions, provided you have large south-facing windows. In summer, for weeks at a time, we often keep the slats more or less horizontal and hardly notice they are down because you can see completely through them. At the moment, it’s cold outside, I’m sitting here without any heating and it’s nice and warm. We have the house and roof really well insulated and also find it very comfortable in summer and are surprised that it does not get warmer inside during the day.

How should the slats be positioned to utilize the most solar energy? Or is it always best for solar gain when the [Raffstores] are fully raised?

I can’t answer this specific question for you, it would be too complicated for me to set the best position each time but maybe there are measurements on this. At the moment they are all fully raised because that also allows the best view outside, which is also valuable even if not measurable. Regardless of the above circumstances, we also installed an air conditioner, not least because of fears of too much heat. I would do that again as well since we also have photovoltaics. For the combination of [Raffstore]/roller shutters you mentioned, I would give a clear yes, nothing else. I hope I was able to answer at least a small part of your inquiry.

Or is it always best for solar gain when the venetian blinds are all the way up?

Yes. Any (even minimal) shading steals sun/heat in this case. Even if the winter sun is negligible in terms of heat input overall. But in the transitional periods, it certainly makes a difference!

The most important for shading are East and West. From the North, the sun hardly ever shines, and in the South, it is so high that the roof overhang catches most of it.

For solar yields, it is best to raise all [raffatore].

Thank you all for the feedback.
Our house is already finished and we have blinds on the south and west sides and roller shutters everywhere on the east and north sides.
However, we only moved in a few weeks ago, so I don’t have any experience yet.
But I fear that if I get the shading wrong in summer, the heat will accumulate in the house and then it will be difficult to get it out again.
As far as I understand, the insulation helps to slow down the heating of the house, but it also means it cools down more slowly once the heat is inside.
And since we also have the parents’ bedroom on the north side, that would be a bit unfortunate.
To be honest, I’m surprised that it’s enough to position the slats crosswise for shading. I would have bet that you have to close them completely in summer.
I even thought that horizontally positioned slats reinforce the sun, and that’s why you should do that especially in winter.
We were told that [Raffstores] help save heating costs. But if fully raised is best in winter, then that statement was probably wrong.

I think you have to find that out individually for your house, but in my opinion, you have very good conditions for it. We never have the blinds fully down to very dark, and I was positively surprised by the low overheating. Our neighbors had all their shutters closed tight all day in the summer, and at the latest then I realized that I would not have wanted that. Of course, some things may be different for you, like roof overhang (we have none), direction, window size and orientation, personal feeling, etc., but I do believe that you made a good choice there. I was very skeptical and a bit afraid because of the large window areas, but that did not prove to be the case.