Sometimes you read posts with claims that sound reasonable but may turn out to be a myth. One claim is not to use impregnated wood for sills as the wood can emit unpleasant odors similar to mold.
When trying to find information, the smell problem seems to depend on how wood was impregnated in the past, which explains why many have issues with houses built in the 70s. From http://www.eurofins.se/tjanster/inomhusmiljo/ex-pa-skadeproblem/lukt-fran-impregnering.aspx
"...Examples of chlorophenol-containing preparations are kp-cuprinol and servarex teknisk. Kp cuprinol was used for pressure impregnation of wood and servarex teknisk was used as a bluing protection for newly sawn wood. These and other similar preparations stopped being used in Sweden at the end of the 1970s. Smell problems from impregnated sills therefore mostly appear in houses built in the 70s."
But today other chemicals are used, right? And the problem with smell should be solved?
From http://www.traskydd.com/1.0.2.0/110/download_302.php
"...Today's NTR-classified impregnation agents do not cause unsanitary odors if NTR wood is built into foundations. In some cases, a particular smell was found from a wood preservative that was used to a lesser extent in the late 1970s. That agent contained pentachlorophenols and was banned already at the end of the seventies."
Why one should have pressure-treated wood in the sill at all is another question, but it may be unwise to alarm those considering it or who already have it in a relatively newly erected building.
Is it a myth that today's impregnated wood should cause the same smell problems as houses from the 70s?
When trying to find information, the smell problem seems to depend on how wood was impregnated in the past, which explains why many have issues with houses built in the 70s. From http://www.eurofins.se/tjanster/inomhusmiljo/ex-pa-skadeproblem/lukt-fran-impregnering.aspx
"...Examples of chlorophenol-containing preparations are kp-cuprinol and servarex teknisk. Kp cuprinol was used for pressure impregnation of wood and servarex teknisk was used as a bluing protection for newly sawn wood. These and other similar preparations stopped being used in Sweden at the end of the 1970s. Smell problems from impregnated sills therefore mostly appear in houses built in the 70s."
But today other chemicals are used, right? And the problem with smell should be solved?
From http://www.traskydd.com/1.0.2.0/110/download_302.php
"...Today's NTR-classified impregnation agents do not cause unsanitary odors if NTR wood is built into foundations. In some cases, a particular smell was found from a wood preservative that was used to a lesser extent in the late 1970s. That agent contained pentachlorophenols and was banned already at the end of the seventies."
Why one should have pressure-treated wood in the sill at all is another question, but it may be unwise to alarm those considering it or who already have it in a relatively newly erected building.
Is it a myth that today's impregnated wood should cause the same smell problems as houses from the 70s?
For my part, just smelling pressure-treated wood is enough to consider it not good to incorporate it into a structure as a sill, floor framework, or walls.
Sure, the smell diminishes after a few years and once it has dried properly. But if there's a risk of moisture then... On the other hand, you're on the wrong track if there's a risk of moisture in the sill.
Of course, today's well-sealed walls and floors eliminate some of the risk.
Sure, the smell diminishes after a few years and once it has dried properly. But if there's a risk of moisture then... On the other hand, you're on the wrong track if there's a risk of moisture in the sill.
Of course, today's well-sealed walls and floors eliminate some of the risk.
Is there really any smell?
It took a number of years, despite mass production with impregnated ties, to discover the problems in the '70s. We will surely discover problems with today's construction methods in the future.pbengtsson said:
I also believe that today's construction methods will be questioned. But letting "myths" persist does not advance development. What's a bit amusing in construction is that there are many claims about how things should be, without anyone questioning whether those claims are true. There's a risk of encountering someone who wants to appear more experienced in construction just because they can point things out without understanding why.
The question is also why build chemicals into the house for no benefit. It only brings risks in the future and unnecessary environmental impact during production. Almost all houses are built without impregnated sill and it's not a problem.
Sure, new treated wood smells, but not nearly as much as it does in houses from the 70s, some of which are uninhabitable without heavily forced ventilation.
Sure, new treated wood smells, but not nearly as much as it does in houses from the 70s, some of which are uninhabitable without heavily forced ventilation.
Sorry to bump a really old thread.
Has anything changed in recent years, or is it still the case that out of old habit (the '70s problem) or for safety reasons, it's not recommended to use newly pressure-treated beams?
Is there actually any evidence that new pressure-treated lumber is a problem?
Has anything changed in recent years, or is it still the case that out of old habit (the '70s problem) or for safety reasons, it's not recommended to use newly pressure-treated beams?
Is there actually any evidence that new pressure-treated lumber is a problem?
Know-It-All
· Västra Götaland
· 12 287 posts
Newer ones don't have the same poison. But a pressed modern sill with sill insulation underneath shouldn't be a problem, I think. One usually uses plastic on the inside anyway.
Pressure-treated sill with sill paper is surely not a problem, it's the contact with the concrete that's the issue. The question is, for what reason would one want a pressure-treated sill?E Edvuld said:
The Timber Guide/Swedish Wood recommends it in their construction descriptions.
For my part, about 6 meters of the sill was replaced a few years ago by a previous owner, with pressure-treated wood.
It just looks like there is mineral wool under it, against the basement wall, but I haven't looked closely yet.
The inspector noted the pressure-treated sills.
So that's why I'm considering whether to go through the job of replacing it again before I try to straighten out my basement ceiling.
For my part, about 6 meters of the sill was replaced a few years ago by a previous owner, with pressure-treated wood.
It just looks like there is mineral wool under it, against the basement wall, but I haven't looked closely yet.
The inspector noted the pressure-treated sills.
So that's why I'm considering whether to go through the job of replacing it again before I try to straighten out my basement ceiling.
Know-It-All
· Västra Götaland
· 12 287 posts
Mineral wool underneath sounds a bit strange. However, the compressed one would be okay if it has syllpapp or syllisolering. Mineral wool, on the other hand, is just wrong if it's in between.
What did the inspector specifically comment on?
Strength class?
For the impregnation itself is done today in consumer products with copper salts that, from what I've read, are considered harmless from a health standpoint even indoors.
It's been 40 years since pentachlorophenol (which gave a nasty smell) was banned and now also CCA.
so...
Unnecessary, but hardly dangerous or something to comment on.
Strength class?
For the impregnation itself is done today in consumer products with copper salts that, from what I've read, are considered harmless from a health standpoint even indoors.
It's been 40 years since pentachlorophenol (which gave a nasty smell) was banned and now also CCA.
so...
Unnecessary, but hardly dangerous or something to comment on.
The remark was as follows:M MagHam said:
Basement:
Unusual odor in the area, see 1.
Pressure-treated/coated timber with rot protection fluid in structural parts.
Microbial growth on structural parts.
Signs of moisture intrusion in walls and floors.
1. To understand the cause and extent of the unusual odor/damage, a continued technical investigation is recommended. Info: Pressure-treated/Coated timber in crawl space can emit a sharp odor which can spread into the living area.
Personally, I don't think it smells particularly much. I have used a dehumidifier in the summer and have heated to about 14 degrees in the winter during the past year since I bought the house.
I also don't see any "active" growth.
Know-It-All
· Västra Götaland
· 12 287 posts
Then the "syllen" is not something to worry about either. The most important thing is that it is dry.
It often tends to smell like a basement if it's a bit cool and damp. When there is microbial growth (=mold?), it is most likely what smells. The sill itself doesn't necessarily have to smell. However, wood and other organic materials have a tendency to "absorb" odors, which causes things like carpets, cushions, pillows, textiles, etc., to typically smell like "summer cottage" (unheated). So after a while with a moldy smell, it might be hard to distinguish the origin, as the sill may have absorbed the odor.
If it's not mold but just a regular somewhat musty odor due to moisture, heat and possibly some extra ventilation can usually remove the smell.
If it's not mold but just a regular somewhat musty odor due to moisture, heat and possibly some extra ventilation can usually remove the smell.