Building moisture after moving in - experiences

  • Erstellt am 2016-03-21 08:37:35

Legurit

2016-03-21 08:37:35
  • #1
Hello everyone,

I wanted to report on how things are going with the drying out of the house.
We had the feeling that we had already ventilated a lot of moisture out during the construction (we were a bit fanatical about airing it out – gladly even again at 11 p.m.); that it was probably far from everything, we had to realize now when we emptied the storage room under the stairs. In the corner lay a wooden mirror that had very exemplary "soaked up" water (exemplary because it didn’t start to rot or mold, but was just very damp). When the room under the stairs was then empty, we walked into the room and had to realize that it was already a bit cooler but above all also felt quite humid. Now it is open, empty, and will be ventilated for the time being. No mold has formed, but I could imagine that with parquet and gypsum plaster it might have looked different.
Otherwise, we measure the humidity in the bedroom, which during the day always drops to about ~49% and then rises again at night to 55% – although I don’t know if that is due to residual moisture or the occupants. (We always set the ventilation system to a lower level at night.)

Another moisture problem we had was with the bathroom exhaust in the upper floor.. but that was also not very well thought out and has little to do with construction moisture – but maybe it helps someone who is planning similarly. Our bathroom exhaust pipe goes through the unheated attic, makes a bend, and then has a pipe divider – one leading upward outside and one downward into a "condensate trap." The only problem was that it was quickly full due to the freezing temperatures and then the water dripped back down the pipe – onto the closing cover of the exhaust unit. Since it was closed, it also pressed a bit against the gypsum board... and that then of course swelled a bit and caused the paint to peel off. This will of course be fixed; the condensate trap was emptied and the pipe is now thickly insulated up to the roof outlet. Hopefully it works better now.
 

Teyla

2016-03-21 10:38:30
  • #2
Hey,

I'm joining in on this post because I searched forever online about construction moisture and unfortunately found very little. Maybe this can help other home builders a bit!

Solid house with clinker facade Kfw40 Construction time: 5 months (early March to late July 2015) Heat pump with integrated central ventilation system with heat recovery, underfloor heating

During the construction phase, we also carefully ventilated by shock ventilation daily to already get rid of as much moisture as possible. After moving in, for 5 months we continued to ventilate by shock ventilation 2-3 times daily, additionally the ventilation system runs on level 2 (of 3) during the day and on level 1 at night.

Since the beginning of the year, we hardly ventilate additionally to the ventilation system because the humidity has continuously decreased. We have placed hygrometers in several rooms to monitor the humidity and ventilate manually if needed, but the air is usually rather too dry than too humid. Now, 7.5 months after moving in, we mostly have around 35-45° humidity, depending on the weather.

As with BeHaElJa, our storage room is also the dampest room. Our storage room is located under the concrete stairs and has neither windows nor a connection to the ventilation system. Therefore, we had two ventilation grilles installed in the door and placed a dehumidifier, and luckily the humidity there is slowly going down to mostly around 50-55°. It still feels noticeably more humid than in the other rooms, but luckily no mold or anything like that.

We are very satisfied with the development and happy that our house is not affected by mold problems. We're glad we decided on the ventilation system since we don't have time due to work to ventilate the house manually several times a day.

By the way, we only manually ventilate now: - the bathroom after showering - the utility room when more than one load of laundry is drying there - the kitchen when there has been "big" cooking.

I hope posts like this one can be of some help to other builders

Best regards, Teyla
 

Sebastian79

2016-03-21 11:17:33
  • #3
I am currently running the ventilation system during the screed drying and hardly ventilate manually anymore.

Contrary to the concerns that were revealed to me back then, hardly any dirt reaches the top of the ventilation unit - only the pre-filters in the exhaust rooms are clogged more often.

We have no condensation on the windows, the readiness for covering is already given on the ground floor & upper floor - without accelerator and after 12 days of screed drying. Although I am still cautious here, because the screed should first cool down...

Nevertheless, I have acquired a total of four construction dryers, which are temporarily turned on, for example, when painting has been done.

I am curious what remains of the moisture at moving in. Construction time so far: 11 months and we still have no floor coverings.
 

Mycraft

2016-03-21 11:39:07
  • #4
g


Pretty long...

Regarding the moisture problem: heating and ventilation!

That's the only way... without heating, the moisture simply condenses at the coldest spots, meaning in your storage rooms... warm air has to go in there, which can take the moisture with it... otherwise, it won't work...
 

Sebastian79

2016-03-21 12:03:37
  • #5
Nope, not long - completely normal with a lot of [EL]. And by the way, good for construction...
 

wrobel

2016-03-21 12:45:33
  • #6
Moin Moin

Based on my own professional experience and that of my brother, leak detection and building drying, I would always use technical drying in a solid house and especially in winter. The costs are low compared to possible damages.

Olli
 

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