Hello!
In 2008, I built a house with a manufacturer that delivered turnkey but used outer wall modules. Local carpenters were hired by the manufacturer for the work after the frame was erected.
Two years ago, I found mold on the floor structure in the attic, and a moisture technician noted heat leakage and that the vapor barrier was not taped at the seams, allowing warm humid air to migrate into the attic.
A complaint was filed with the house manufacturer.
No problem, they undertook to both tape the seams and add new, even thicker insulation.
Now I've been thinking further and after having an ooooverwhelming number of flies indoors all winter (from just a few new ones per day to hundreds in one day!)
I now think:
* if the vapor barrier is properly done, air should not pass through it, and even less so flies.
* the flies are not a problem in the summer, indicating they do not enter indoors via windows/doors, overwinter, and wake up.
* if the vapor barrier was not taped in the ceiling, it probably isn't in the walls.
* the flies likely get in via the attic, crawl down and snooze sweetly behind the insulation. They wake up, sense warmth they crawl towards, and suddenly the warmth leads them between the untaped plastic sheets and they're inside. Since we have a panel ceiling, there are cavities above the ceiling molding between the panel boards.
* if the flies can get in, warm air can also escape, and if mold forms in the wall, it's much harder to detect.
Can someone help me think this through?
I tried to file a complaint after the first winter with the flies, but the company brushed it off, and I eventually had to give up because I didn't have the knowledge I have today. I also had other complaints to fight over which were considerably worse.
In old pictures from the construction time, not a single piece of tape is visible, but the pictures are a bit poor, and nothing says the tape didn't come after the picture was taken, except for one picture where you can see the interior wall studs are up but it doesn't look taped beforehand.
Should I cut a hole in the wall and check for tape/no tape and if there are any signs of mold or even mold?
I would be super grateful for help to discuss this!
In 2008, I built a house with a manufacturer that delivered turnkey but used outer wall modules. Local carpenters were hired by the manufacturer for the work after the frame was erected.
Two years ago, I found mold on the floor structure in the attic, and a moisture technician noted heat leakage and that the vapor barrier was not taped at the seams, allowing warm humid air to migrate into the attic.
A complaint was filed with the house manufacturer.
No problem, they undertook to both tape the seams and add new, even thicker insulation.
Now I've been thinking further and after having an ooooverwhelming number of flies indoors all winter (from just a few new ones per day to hundreds in one day!)
I now think:
* if the vapor barrier is properly done, air should not pass through it, and even less so flies.
* the flies are not a problem in the summer, indicating they do not enter indoors via windows/doors, overwinter, and wake up.
* if the vapor barrier was not taped in the ceiling, it probably isn't in the walls.
* the flies likely get in via the attic, crawl down and snooze sweetly behind the insulation. They wake up, sense warmth they crawl towards, and suddenly the warmth leads them between the untaped plastic sheets and they're inside. Since we have a panel ceiling, there are cavities above the ceiling molding between the panel boards.
* if the flies can get in, warm air can also escape, and if mold forms in the wall, it's much harder to detect.
Can someone help me think this through?
I tried to file a complaint after the first winter with the flies, but the company brushed it off, and I eventually had to give up because I didn't have the knowledge I have today. I also had other complaints to fight over which were considerably worse.
In old pictures from the construction time, not a single piece of tape is visible, but the pictures are a bit poor, and nothing says the tape didn't come after the picture was taken, except for one picture where you can see the interior wall studs are up but it doesn't look taped beforehand.
Should I cut a hole in the wall and check for tape/no tape and if there are any signs of mold or even mold?
I would be super grateful for help to discuss this!
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I am doubtful that you can get the help you need this way. There are many conditions you would have to explain for us to gain a clear picture.
If I were a fly, I wouldn't bother crawling through untaped holes in the vapor barrier. I would follow the fresh air in wherever it enters. If you have a modern ventilation system with some pressure, the flies are unlikely to enter through holes in the plastic.
If I were a fly, I wouldn't bother crawling through untaped holes in the vapor barrier. I would follow the fresh air in wherever it enters. If you have a modern ventilation system with some pressure, the flies are unlikely to enter through holes in the plastic.
Well, modern ventilation systems (FTX) usually operate under pressure, to prevent blowing warm air into the insulation, where the air cools and moisture can condense.J justusandersson said:
In our house, we had a lot of flies and especially lacewings the first two winters. Probably a residue from the construction time. But now, after five years, we very rarely see an insect inside (except for the occasional tick that comes in with the cats).
But if you're a comfortable fly, you'll probably enter where it's very easy to get in, and to the attic, it's pretty much an autobahn. Then when it gets cold, it's easy and cozy to crawl behind the insulation and so on...J justusandersson said:
It's not reasonable that the thousands upon thousands of flies that crawl into us over a winter would have passed indoors in the summer without us noticing.
Additionally, we saw piles of dead (sleeping?) flies behind the insulation in the ceiling beams and outer wall that winter we were up in the attic for the mold problem.
Regarding ventilation, we have a poorly functioning natural ventilation system, which is a story in itself in this "failed" house construction...
Even if you have a ventilation system that is fully adjusted with a negative pressure, the result is still a slight positive pressure closest to the attic floor, due to the laws of physics. (That's why it's set with negative pressure.) With natural ventilation, the positive pressure is greater in the upper part of the room/house. The point is the same, if insects come in, it's more likely to happen closer to the ground floor. In SkogsKajsa's case, it seems like they are already indoors for some reason.
When living in the forest and countryside, according to my personal experience, the presence of insects depends on something near the house, like wetlands, livestock, or something else. My wife and I often have problems with flying ants on warm summer evenings. They like to sit on a warm metal roof outside the bedroom windows and have a way of getting in no matter how tightly you close things.
When living in the forest and countryside, according to my personal experience, the presence of insects depends on something near the house, like wetlands, livestock, or something else. My wife and I often have problems with flying ants on warm summer evenings. They like to sit on a warm metal roof outside the bedroom windows and have a way of getting in no matter how tightly you close things.
There is a riding school nearby, but then all the neighbors, especially those living even closer, would have the same problem with flies. That is not the case. And the flies invade the upper floor. Only a few make it down to the first floor.J justusandersson said:
Furthermore, since yesterday, I have stuffed tufts of toilet paper into every gap in the ceiling at the moldings and last night and today for the first time, we hardly had any flies at all. Just a few, which we suspect were well hidden during the big small game hunt we conducted yesterday after the tufting...
But then you are on the right track!
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· Etelä Pohjanmaa
· 2 467 posts
Since you have added more insulation, the old insulation will now become warmer than it has been previously during winters. This will awaken old fly larvae. It will likely subside on its own.
But this is where the manufacturer claims that the flies entered, in their thousands, through open windows in the summer and hide and hatch in the walls. According to Anticimex, they cannot hatch in the walls unless there is moisture in the walls, which I really hope there isn't, but you never know with potential heat leakage...?J justusandersson said:
But egg hatching and larvae require a humid environment to work?F Finndjävel said:
This is also the second winter after the additional insulation.