We are expanding our single-family house with a family room on a crawl space. The carpenters have laid the sill, pressure-treated 95*22 NTR AB, under the entire length of the floor joists instead of on the foundation wall all the way around. The gaps formed on the wall are supposed to provide ventilation to the crawl space.
I can't find this variant with the sill following the floor joists instead of the foundation wall anywhere, is it an accepted building method that is okay? Thin with 22*95?
More pressure-treated wood has been used as support in the crawl space—I can't figure out if it's wrong to use pressure-treated wood or if it's just unnecessary? Purely toxic impregnation (Pentachlorophenols) that was the culprit in old pressure-treated constructions is no longer a problem, rather that pressure-treated wood can mold and then smell, does this also apply to "modern" impregnation? But if it is so humid that pressure-treated wood molds, you would have had problems with untreated structural wood anyway? Or can modern pressure-treated wood cause smell problems in conditions where untreated wood would not have caused any issues?
I can't find this variant with the sill following the floor joists instead of the foundation wall anywhere, is it an accepted building method that is okay? Thin with 22*95?
More pressure-treated wood has been used as support in the crawl space—I can't figure out if it's wrong to use pressure-treated wood or if it's just unnecessary? Purely toxic impregnation (Pentachlorophenols) that was the culprit in old pressure-treated constructions is no longer a problem, rather that pressure-treated wood can mold and then smell, does this also apply to "modern" impregnation? But if it is so humid that pressure-treated wood molds, you would have had problems with untreated structural wood anyway? Or can modern pressure-treated wood cause smell problems in conditions where untreated wood would not have caused any issues?
I'm no expert, but I would really hesitate to use treated wood in residential expansion. What is the reason for using pressure-treated wood? It gives off strange vibes, and there must be other construction solutions where it isn't necessary.
Edit:
If I understand crawl space correctly (I don't have one myself), you want to avoid an outdoor air-ventilated crawl space, right? And if you want to ventilate the crawl space, it's better to make a hole in the wall for ventilation.
Edit:
If I understand crawl space correctly (I don't have one myself), you want to avoid an outdoor air-ventilated crawl space, right? And if you want to ventilate the crawl space, it's better to make a hole in the wall for ventilation.