Hi!
I have a two-year-old Fiskarhedenvilla with a wood panel ceiling. I've installed some lighting afterward and have made various holes for spotlights and such.
There are no visible nail heads in the ceiling, so I assume it is installed with clips and screws, but under the moldings at the ends of the ceiling, it seems to be nailed.
When I had my hand up in a spotlight hole, I discovered that you could feel a couple of nail heads on the upper side of the lattice against the plastic, although the plastic doesn't seem to be punctured. I also broke off a couple of ceiling moldings to gain access; these are nailed with 50mm finishing nails. There are vertical battens in the outer walls as an installation layer, list+gypsum+battens are about 50mm thick, so there's a borderline risk even there that the plastic might be punctured.
Is this something to worry about?
The house has exhaust ventilation...
I have a two-year-old Fiskarhedenvilla with a wood panel ceiling. I've installed some lighting afterward and have made various holes for spotlights and such.
There are no visible nail heads in the ceiling, so I assume it is installed with clips and screws, but under the moldings at the ends of the ceiling, it seems to be nailed.
When I had my hand up in a spotlight hole, I discovered that you could feel a couple of nail heads on the upper side of the lattice against the plastic, although the plastic doesn't seem to be punctured. I also broke off a couple of ceiling moldings to gain access; these are nailed with 50mm finishing nails. There are vertical battens in the outer walls as an installation layer, list+gypsum+battens are about 50mm thick, so there's a borderline risk even there that the plastic might be punctured.
Is this something to worry about?
The house has exhaust ventilation...
No. The rule is that walls/ceiling/floor should be tighter on the inside than the outside. A few nail holes from brads can hardly let in more air than the material itself lets out. At least not as long as the nails remain in place. If you have active exhaust ventilation, you should also have negative pressure in the house.
In "natural" houses that are claimed to "breathe," which are built without moisture barriers, the material suppliers emphasize that aspect. Therefore, there are lists of moisture permeability through different materials, such as gypsum, etc. The heat is assumed to push the moisture all the way out if the materials on the inside stop a little while those on the outside are more diffusion-open.
It works very well in, for example, old log cabins that haven't been additionally insulated from the outside. But I view it with utmost skepticism in new houses. If you have outdoor gypsum behind the facade, it is an example of material that is slow in terms of moisture migration. Then it's more important that the vapor barrier is intact.
Best regards, Findus
In "natural" houses that are claimed to "breathe," which are built without moisture barriers, the material suppliers emphasize that aspect. Therefore, there are lists of moisture permeability through different materials, such as gypsum, etc. The heat is assumed to push the moisture all the way out if the materials on the inside stop a little while those on the outside are more diffusion-open.
It works very well in, for example, old log cabins that haven't been additionally insulated from the outside. But I view it with utmost skepticism in new houses. If you have outdoor gypsum behind the facade, it is an example of material that is slow in terms of moisture migration. Then it's more important that the vapor barrier is intact.
Best regards, Findus
Hello!
Thanks for a detailed response. Now it seems that the spot I looked at on the walls had a missing kortling, it appears to be inside so long nails in the trim don't matter as the plastic is clamped behind the kortling and the trim nails hit it instead of going through the plastic and into an empty space.
It's outdoor gypsum in the house, though!
The worst-case scenario is that all the ceiling panels are nailed with too long nails at the ends, also as close to the roof ventilation as possible all the time (soffit ventilation and ventilated ridge) so according to your theory, the air that finds its way out should be able to escape quite easily considering it's completely open from the "attic"?
Thanks for a detailed response. Now it seems that the spot I looked at on the walls had a missing kortling, it appears to be inside so long nails in the trim don't matter as the plastic is clamped behind the kortling and the trim nails hit it instead of going through the plastic and into an empty space.
It's outdoor gypsum in the house, though!
The worst-case scenario is that all the ceiling panels are nailed with too long nails at the ends, also as close to the roof ventilation as possible all the time (soffit ventilation and ventilated ridge) so according to your theory, the air that finds its way out should be able to escape quite easily considering it's completely open from the "attic"?