Hello everyone,
I wanted to get your opinions on the topic of efflorescence on our newly built house. I’ve already read several reports from others and understand that this is fundamentally a complex issue with many influencing factors. Within certain limits, it can be normal; sometimes it’s due to poor workmanship, and sometimes both factors play a role.
In recent months, we’ve had a lot of unusually heavy rainfall, which likely encourages efflorescence. We also live in a new housing development where most houses currently have efflorescence. Ours is particularly severe, which might be partly due to the type of brick, which can absorb more water (Wiesmoor earth-tone).
The affected sides on our house are primarily those exposed to weather (south/east and south/west), while the other two sides show very little. It’s especially visible on the window sills (a common spot on many houses, see photos 1-2) and the side gable below and around the window (photo 3), but also on a corner edge (photo 1, right side). What confuses me most is the efflorescence and noticeable residual moisture at the base of the wall (photos 1, 4), even though we have a drainage membrane, ventilation gaps, and drainage installed.
Regarding the window sills, I looked through some photos from the construction phase, and it seems that Alujet foil was applied everywhere. I can upload those if anyone is interested.
What’s your assessment? Is it due to the combination of the brick and heavy weather plus possibly the mortar? Should we simply clean off the efflorescence and expect it to subside over time? Or do you think there might be a more fundamental problem? By the way, brushing and rinsing off the deposits doesn’t work well, which seems to suggest it’s more likely nitrate salts than common salt, right?
Thanks in advance and best regards
Ubibubi

I wanted to get your opinions on the topic of efflorescence on our newly built house. I’ve already read several reports from others and understand that this is fundamentally a complex issue with many influencing factors. Within certain limits, it can be normal; sometimes it’s due to poor workmanship, and sometimes both factors play a role.
In recent months, we’ve had a lot of unusually heavy rainfall, which likely encourages efflorescence. We also live in a new housing development where most houses currently have efflorescence. Ours is particularly severe, which might be partly due to the type of brick, which can absorb more water (Wiesmoor earth-tone).
The affected sides on our house are primarily those exposed to weather (south/east and south/west), while the other two sides show very little. It’s especially visible on the window sills (a common spot on many houses, see photos 1-2) and the side gable below and around the window (photo 3), but also on a corner edge (photo 1, right side). What confuses me most is the efflorescence and noticeable residual moisture at the base of the wall (photos 1, 4), even though we have a drainage membrane, ventilation gaps, and drainage installed.
Regarding the window sills, I looked through some photos from the construction phase, and it seems that Alujet foil was applied everywhere. I can upload those if anyone is interested.
What’s your assessment? Is it due to the combination of the brick and heavy weather plus possibly the mortar? Should we simply clean off the efflorescence and expect it to subside over time? Or do you think there might be a more fundamental problem? By the way, brushing and rinsing off the deposits doesn’t work well, which seems to suggest it’s more likely nitrate salts than common salt, right?
Thanks in advance and best regards
Ubibubi
Ubibubi schrieb:
Would you say that in my case it's definitely worth it, or would that be like using a sledgehammer to crack a nut? The surveyor might cost around 300€ (about $330), and the damage could have various causes—construction defects, leaks, improper drainage, etc. Repairs could be expensive or relatively affordable; you just don’t know what’s going on behind the scenes, what’s rotting away, or what is developing there.
G
Gerhard19844 Nov 2025 12:19Hello Ubibubi... What happened with you, or were you able to solve the problem?
I have a similar situation and was advised to apply a water repellent treatment to the bricks / window sill to prevent the bricks from absorbing water.
The window installer says he sealed everything correctly.
I have a similar situation and was advised to apply a water repellent treatment to the bricks / window sill to prevent the bricks from absorbing water.
The window installer says he sealed everything correctly.
For me, there was significantly less in the second winter, and the salt has since been washed out. Last year, I also applied the wall sealant from Mellerud on all the window sills. However, I cannot say how much of the difference is due to the sealant and how much is simply the effect of time.
I mainly still see moisture during rainy periods on the side gable, since that side is exposed to the weather.
I mainly still see moisture during rainy periods on the side gable, since that side is exposed to the weather.
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