ᐅ How to bring natural light into a staircase?

@ Roger

You probably want to test me or pull my leg?

The insulation value of 4 mm (0.16 inch) single-pane safety glass corresponds to the glass panel in your front door. It’s acceptable for an area of just under 0.12 m² (1.3 ft²).

Double casement windows start at about 1.3.

Regards, Bauexperte


Bauexperte, on the go

Hello,

why would I want to test you? Our energy technician says that KFW 55 can only be achieved with 0.7 windows. If both are significantly worse than 0.7 windows, this is definitely important for the calculations and must be taken into account. Thanks for the information.

Regards,
Roger

Hello Roger,

Shadowblues schrieb:

Our thermal engineer says KfW 55 can only be achieved with windows that have a U-value of 0.7. If both are significantly worse than 0.7 windows, this is definitely important for the calculation and must be taken into account. Thanks for the info.

KfW 55 is not solely dependent on the glass value; how could it be? Where, for example, certified RC II windows are installed, the value increases so much that—if your energy consultant were correct—no KfW 55 efficiency house with certified windows would be possible. Since this is not the case, your consultant is either mistaken on this point or you may have misunderstood him.

What about the floor-to-ceiling patio doors in your attic or upper floor? I don’t know which house type you are building. Do you have French balconies planned there or are they mullion elements? If the latter, the glass value no longer matches your energy consultant’s statement either. Unless you have installed passive house (PH) windows; then laminated safety glass (VSG) works as well.

For example, the U-value of the glass in our windows with triple glazing is 0.6 Watts/m²K (0.11 BTU/h·ft²·°F). This looks good—and it is—but the overall U-value of the window must also be considered. If safety glass (laminated glass, VSG) is used, it already rises to 1.2 Watts/m²K (0.21 BTU/h·ft²·°F). Building a KfW 55 efficiency house requires (based on our building specifications) “only” solid brickwork, insulation under the slab (which, in my personal opinion, is the biggest nonsense in house construction), and supervision by an external expert. Either way, a daylight spot measuring 35 x 35 cm (14 x 14 inches) with single-pane safety glass does not invalidate the certification.

Best regards, Bauexperte

Bauexperte schrieb:



KfW 55 is not solely dependent on the value of the glass; how could it be? Either way, a daylight spot measuring 35 x 35 cm (14 x 14 inches) with single-pane safety glass does not affect the certification.

But what if you really want it?
The same goes for the insulation under the waterproofing membrane.
It might make sense occasionally.
If it is not strictly required, I would simply leave it out or just ignore it.
In my opinion, it's just "window dressing."

Hello, I don’t have any firm requirements. I would like to build a KfW 55 house. For this, I hired an architect and a thermal expert. The architect went ahead and installed this Swedish panel without consulting me, and the thermal expert required higher insulation and upgraded windows. It didn’t go perfectly, but as a client, you’re often at the mercy of these processes. So now the expert is supposed to confirm whether it’s acceptable or not, since they have to sign off on it.
Best regards,
Roger