ᐅ Drafts at the corners of the windows?

Hello everyone,

I bought a 2-year-old house, a prefabricated timber frame construction.
Some small details were not fully completed by the previous owners, for example, the interior window sills are missing.
This results in the following situation, see photos.
You can feel a draft through these openings if you place your hand over them.
How would you assess this?
In my research, I have heard everything from "just install the window sill and it's done" to warnings about drafts, leaks, and mold being almost inevitable...
A blower door test was performed at handover, resulting in a n50 value of 0.63 h⁻¹.

Thank you

Seglock schrieb:

How do you evaluate this?

Building defect. Nothing more, nothing less. Faulty window installation is possible.

Seglock schrieb:

In my research, I’ve heard everything from “just insert the window sill and that’s it” to “warning, leaks and mold are inevitable”…

The latter is not inevitable, but possible. The former is DIY shoddy work, but it might work. It’s like “repairing” a hole in a windowpane with chewing gum.

Seglock schrieb:

The blower door test was done during handover, nl50 = 0.63 h

Someone probably ran the test, found the drafty holes, sealed them with tape, then swore on everything to fix the defects after passing the test...

nordanney schrieb:

Construction defect. Nothing more, nothing less. Faulty window installation is conceivable.

The latter is not inevitable, but possible. The former is amateurish DIY work but might still hold. It’s like “repairing” a hole in a pane of glass with chewing gum.

Apparently, someone ran the test, found the drafty holes, sealed them with tape, and then swore on everything in the world to fix the defect after passing the test...

Thank you for the response.
What would be reasonable when weighing the risks? Should I just go ahead and hope it works out, or should I raise the issue with the developer and possibly slow down renovation work, etc.?

Seglock schrieb:

Opening a case with the developer

This is the correct and initially the only way. Everything else is only an option if the matter ultimately has to be resolved in court.

Clarify the matter with the seller directly. In some cases, defects are compensated with a financial payment (price reduction), in which case you would have no claim against the construction company.

What does your purchase contract say about defect-free condition and liability for defects?