
Hi everyone,
I live in a rented top-floor apartment (Dachgeschoss) in Berlin and I’m trying to find a no-drill blackout solution for this unusual window setup. Budget is max 100€. Cheaper solutions are welcome too.
Details:
– Large central window plus two angled side windows (non-standard shape)
– Main goal is block sunlight / blackout, and ideally reduce heat in summer too
– Since I rent, I can’t drill into the wall or frame
– I’m looking for things like:
– suction cup blackout blinds/curtains
– no-drill (Klemmfix) blackout blinds
– removable blackout film
– custom DIY renter-friendly hacks
Important:
– The side windows are angled, so standard curtains or normal roller blinds may not fit well.
– I’d prefer something easy to remove/open because I still need ventilation.
– I’ve seen portable blackout blinds with suction cups (often sold for baby rooms or travel) — has anyone used those long-term?
– Also curious if reflective thermal foil or similar hacks work well for Dachgeschoss heat.
Has anyone solved something similar in Germany/Berlin and can recommend products (IKEA, Amazon.de, Bauhaus, Jysk, etc.) or clever setups?
Would love ideas, especially if you’ve dealt with odd-shaped windows like this.
Thanks!
https://i.redd.it/82n1xw8mh6xg1.jpeg
Posted by devopsingg

22 Comments
Setup some solar panels lol
Reflective thermal foil on the outside.
there’s some blackout options you can cut to size and use with velcro (one side is black and the other silver). Not the prettiest but works
Just install curtains + AC
Spiegelfolie 👍 funktioniert super und einfach
You can drill as a renter
Aluminium foil. I use it.
White tape.
Edit: Add some newspapers too.
So what if you rent? Drill then remove and plaster when you move out. What’s the problem?
I would completely remove the middle window and replace it with the outdoor unit of a split air conditioner. This would be integrated into a custom-made frame that seals the window opening against adverse weather and supports triangular, hinged, reflective panels covering the left and right windows.
It might need some kind of brace or support down to the inner and outer windowsill so the frame doesn’t have to bear the weight of the unit. But: no screws on the window frame, on-demand darkness, and cool air.
Adhesive sun film, mirror, plastic, is self applied and should be enough, decent cost, it may peel off in time. Roller blind with suction cups, more solid option, may cost a bit more, yes you can cut and put the suction cups on angled corners but those parts will not be, well, rollable.
https://www.soldera.de/Sonnenschutzfolien:::279.html
Top floor is hottest in summer and coldest in winter. Just a note, for next time. It’s why Dachgeschoss was probably available at all.
We were in a similar situation when we were renting. Third floor, big wall of glass facing south.
Eventually we bought mirror foil. It’s important that you do always to the full pane and that you do it on the outside. We couldn’t use our balcony after that, as it was like being cooked from both sides, but the inside was soo much more bearable.
At first we didn’t have enough so one window went without treatment for a few days, until the next roll got delivered, which was the perfect opportunity to measure the difference using two identical thermometers:
I put them on the window frame, they were small and lightweigh enough that they would just stay there. The difference: 10 degrees Celsius
It was ABSOLUTELY worth it and the Vermieter asked us to leave it on after we moved out.
Search for Schuette Thermo Wabenplisse (Thermo x Honey). Send them a picture of the windows with measurements and ask for a Solution.
The reflective foil works really well, I put it inside though. I bought two rolls for the current apartment but never put them on as it wasn’t that hot during the last summers compared to living in a top floor (there my room fell like a sauna and the foil really helped) before that
I second the advice to use reflective thermal foil (Spiegelfolie).
That said, if you show this to an experienced decorator / seamstress, it is possible to sew custom-made black out curtains. For the unusual-shaped windows, I would use 3 “Vitragestangen”, one on top, one in the middle and one on bottom. Problem will be the lack of flexibility with such a set-up.
IMO the ideal solution would be “Faltrollo Plissee” in a custom shape, but that is going to be expensive.
You are allowed to put nails and small screws into the window frame and or drill into the wall. The landlord can ask you not to, but they cannot really stop you. You have a right to block the sun with a curtain.
If you are determined not to drill into the window, look for “Klemmträger”.
Buy XPS and cover the window
Then go to the bauhaus and get the black foil paper to cover it and enjoy your day under it’s shadow man
Plants
Used to live in Dachgeschoss a few years back. I had a curtains but the apartment used to get cooked still. Only solution was getting a cooler (a fan which can throw water) which was around 200 euros. Still have it 4 years later and works better than ever even though now I live in a hinterhaus where the sun barely shines
Two things I’d do; there are UV blocking foils that are relatively easy to remove later that can block 50-60% already (to be mounted on the outside), which helps me in my attic. And then some nice blinds of this foldable paper sort for inside. There are some that you can pull from both sides, top and bottom, which can help configure the light depending on sun intensity and angle.
The ghetto-hardcore berlin option is ofc taping a silver or gold rescue blanket…