ᐅ Condensation on window frames in a newly built home from 2023

Hello everyone,

I have a question regarding roller shutter boxes/windows. Our house is a newly built single-family home from 2023. This past winter was the first really cold one. When nighttime temperatures dropped below -10°C (14°F), we noticed condensation around the corners of the window frames on the north and east sides of the house, where the cold wind mostly came from. This happens just below the maintenance hatch of the roller shutter box. I also placed my hands against several of the affected windows and could feel a very slight draft in some spots. Since it hasn’t been that cold in the previous two years, we never noticed this before and there was no condensation. Now that temperatures are rising to around 0°C (32°F) and above, the condensation has disappeared.

I contacted our construction company with the attached photos, and they sent a window installer to take a look. He said this is completely normal with today’s building methods, no action is needed, and there is no risk of mold developing. He suggested that at most a silicone seal could be applied around the corners to stop the air from coming through. I was surprised by this statement, but since I don’t know much about it, I accepted it for now and wanted to ask here for an independent opinion.

Is this really normal for modern houses, even though the roller shutter boxes themselves are insulated? By the way, we did not perform a blower door test before moving in because I planned to do it through acquaintances, but the software malfunctioned on the day it was scheduled. I don’t know if this issue would have been detected then. If this window behavior is normal, probably it wouldn’t have shown up?

Ubibubi schrieb:
and they sent a window installer to take a look. He said that with today's construction methods this is completely normal, there’s no need for action, and no mold will develop.

Sorry, that is simply nonsense. With modern building techniques, you might at most get slight moisture on the bottom of the glass on large window surfaces. What you are showing is a serious problem—poor workmanship, insufficient insulation, incorrect installation, or something similar.

Ubibubi schrieb:
He said he could at most apply a silicone seal around the corners to stop the air from coming through.

From the start, the windows should have been installed with frames designed so that no air can pass through at all. That is how modern construction works, not this leaky mess.

Ubibubi schrieb:
Is this really normal in modern houses?

No.

Hello nordanney,

Thank you for your response.

For the sake of completeness: The window installer who came for the inspection is not the same company that the construction firm originally hired for the installation.

I also found the explanation rather questionable.

Ok. In the end, it doesn’t matter. Report the defect and demand a proper repair.