ᐅ KfW70 House – The Dilemma: Roller Shutters

Hello everyone,

I need your help:
We are currently building a single-family house (KfW70 standard, 160 m² (1,722 sq ft), no basement) and did not include roller shutters in the contract with our general contractor. Originally, we planned to install exterior roller shutters mounted in the window recess beneath the facing bricks. The more I see this solution on other houses, the less attractive I find it. Therefore, I am currently looking for possible alternatives.

The most appealing option would, of course, be electric built-in or external roller shutters. However, I keep hearing that these always cause thermal bridges, which is obviously undesirable (if thermal bridges really are an issue with these). In our new development, I have recently noticed that about 90% of the houses have these types of roller shutters installed.

So, what is the reality? Can external roller shutters be installed without major problems? Or should they be avoided and alternatives considered?
What have you installed? If you have external roller shutters, how did you manage it? Additional insulation, insulated shutter boxes?

For your information:
The wall structure is as follows: 17.5 cm (7 inches) aerated concrete, 16 cm (6 inches) insulation, 4 cm (1.5 inches) air gap, 11.5 cm (4.5 inches) facing brick.
The current stage of construction: foundation slab poured today.

Thank you in advance!

Have you already informed the contractor about your plans? Our foundation slab was poured on a Friday, and by the middle of the following week, the ground floor was completely built with masonry / exactly one week later the precast ceiling was installed. After that, no changes are possible.

The contractor is already informed. I hope we can discuss and resolve the issue directly on Monday.

Roller shutter boxes are always insulated – there is naturally a thermal bridge, but it is negligible.

I would just do it that way...

Please note that this will reduce your lintel height—or rather, part of the window opening will become the roller shutter housing (you don’t want to plan for 2.10 meters (7 feet) and then end up hitting your head). Also, keep in mind that thermal bridging is generally negligible in this case.

Alternatives could be, for example, venetian blinds (at least visually)—roller shutters don’t look very appealing from the outside (although it’s not a major issue).

There are always pros and cons as usual...

External roller shutters:

- Appearance
- Accessible only from the outside for installation / motor replacement, etc. (which can be tricky on upper floors)
- Box size can be large for taller windows
+ Can be retrofitted
+ No thermal bridges

Integrated roller shutters:

- Thermal bridges
- Interference with telephone signals
- Reduced window opening height
+ Cost-effective
+ Easier maintenance / installation

So, you really have to decide for yourself whether you can live with the less attractive appearance or the thermal bridges.