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Wood treated against decay

Wood treated against decay

Wood treated against decay

(OP)
Does anyone know of anything in the Ontario Building Code (or any other Code or Standard) that prohibits the use of wood treated against decay, for the studs and sole plate of basement partitions in a house? The studs and wall plate will be covered by drywall, so I see no danger of a child ingesting it. I was unable to find anything in the Code prohibiting it, but an architect told me it was not permitted and that is why he did not specify it.

RE: Wood treated against decay

It may just be an objection to certain types of treatment like CCA (Link). I don't know of a specific code reference however. Maybe Simpson or CWC could help?

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

RE: Wood treated against decay

I would also think as long as your sole plate (the one in direct contact with the concrete) were treated then the studs wouldn't require it.

RE: Wood treated against decay

(OP)
ok, thanks. Treating the studs depends a bit I suppose on how high the water rises should the sump pump fail, given that the pump is currently running all the time and there is a constant flow of water into the sump even now although there has been no heavy rain for several weeks. As to my question, the Code does seem to allow wood treated against decay to be used within a residence, so long as it is one of the approved chemicals for use in a residence. Thanks to Kootk and Jayrod12 for your responses. Very much appreciated.

RE: Wood treated against decay

I don't think you should be worrying about the what-if the pump fails. If we accounted for all of the what-ifs then everyone would live in a 12" thick walled concrete bunkers and drive armoured vehicles.

Although it is odd that the sump runs pretty well all the time. Any idea what the groundwater level is like? People should not be building their basements below the water level.

RE: Wood treated against decay

(OP)
To Jayrod 12 - It seems to be a perched water table. The soil is a stiff clay. The new basement is unusually deep, being 3 feet below the old adjoining basement floor. I don't know if the sump pump runs all the time but the water is a constant significant and steady stream running into the pit, so I would expect the pump to have to come on fairly frequently.

While I do appreciate your points and the need for sensible risk assessment, I don't think that an armoured vehicle or 12" walls are appropriate analogies to buying and installing a generator as back-up to a sump, especially considering the 2 extreme weather event we had in Torono in one year. In fact, after last year's events, I know a number of people (including engineers) who have installed generators.

It does seem to me that the cost of a back-up generator is not so much (they now have relatively quiet ones; my neighbour installed a $280 generator just before last year's ice storm and managed to keep his furnace running with it) and the consequences of the battery running out during events like a rain deluge in the summer of 2014 or the ice storm of 2014, are quite significant damage to the basement.

I had nothing to do with them building the basement so low. I was called in after they dd that. As an engineer, it is my job to find a technical solution for what the architect wants (even after the fact).

Please don't take the following the wrong way, because I value your responses, and they are well thought out and knowledgeable, but a very wise lawyer who regrettably passed away at a relatively early age, told me never to argue from analogies because an analogy "is not the same thing" and can be torn apart in court. His comment made sense to me and since then I have restrained myself from using anologies, although sometimes they are just too tempting. Anyway, thanks agin for your help. Much appreciated.

RE: Wood treated against decay

You make fair points. It was obviously a gross exaggeration. I definitely agree with providing redundant systems to protect yourself. My intent was I don't feel as though treated studs should be required because the basement "might" flood from the sump pit not running properly. I doubt that flooding once or twice in their service life would cause decay.

RE: Wood treated against decay

Ajk1:
Most bldg. codes say the sill plate should be (any wooden member should be) treated because it is in direct contact with concrete or masonry. The studs in the basement do not have to be treated if they are not in direct contact with the concrete. They certainly don’t have to be treated because the bsmt. might flood at some time. Furthermore, if the concrete or masonry is not in direct contact with soils or exposed to the weather, I think you can find an exception for needing the wood treatment. The older treatment methods and materials are pretty much of the market, I don’t think you will find them at most lumber yards or big box stores. But, again an exception, I believe some of the older treatment methods/materials are still available for industrial and agricultural uses and in bigger timber sizes. I believe I’ve seen exceptions for the continued use of the old treatments when the lumber is not exposed to human contact, but mostly you just can’t get it any longer. To extend the extreme exaggerations a little, I’ve always put signs in my bldgs. and on my playground equipment saying... “people, please feed your children people food, so they quit eating the studs and posts.”

RE: Wood treated against decay

(OP)
To Jayrod and dhengar: I take your points and agree. Thanks very much.

RE: Wood treated against decay

For requiring treated lumber in Canadian code (correct me if I am wrong here):
-Any wood element within 6" of final ground elevation must be pressure treated or protected with 6mm poly;

For designing with treated wood there are no restraints on where you can and can't use it, you just factor the strength down with your Kt value. The actual factor depends on the situation but usually it is 0.70; check OS86 for the actual value

RE: Wood treated against decay

(OP)
To Signious- I believe that the Kt factor for wood treated against rot that is incised in 0.75 for bending and some other actions, in the 2010 edition of the Canadian Wood Manual. Most wood treated against rot is incised, but there is some that is not. I take the same meaning from the Code as you have, about 6 mil poly under the sole plate. Personally I don't like wood in a basement, but if it has to be used there, I would specify that it all (studs and sole plate) be pressure treated against rot.

I am not so sure that being wetted only when there is flood will not cause rot, when it is considered that it is covered by drywall and may take a long time to thoroughly dry out.

Like you, my reading of the Code is that lumber treated against rot, in a residence is permissible if it is done with a chemical approved for residences. Thanks for your comments. Much appreciated.

RE: Wood treated against decay

Ajk1:
Every time the bsmt. floods you will have to remove and replace all of the wet sht. rock, so that things can dry out. Or, you’ll be growing mold in the walls and on the sht. rock as if it’s a second occupation. I don’t care if you use treated studs, but I also don’t think most bldg. codes require that. In any case, that kind of bsmt. flooding is a serious problem and that should be addressed before you do much finishing down there. That is really a life (and marriage/family) altering issue.

RE: Wood treated against decay

I was going to point out that "wet" drywall IS a mold and dampness problem by itself.

The water on the floor - though draining to a sump will help - will cause the drywall to seep up though the Not-pressure treated trim molding and cause the insulation and drywall and trim and studs to rot out and mildew.

That OK though - if the sump pump goes out when there's no power the water in the basement will just freeze up. 8<)

RE: Wood treated against decay

(OP)
Right about not a Code requirement to treat wood in the basement against rot. It is just my preference, that's all. Most people would likely not do so. Good information from you all, and much appreciated. Thanks.

RE: Wood treated against decay

It would be interesting to run the numbers comparing the increased cost for P.treated lumber throughout the basement vs. the probability and expected cost of a non-insured flood damage reno.

Tossing quick numbers around in my head makes me think it is a lot closer than you'd think.

RE: Wood treated against decay

If you have a non-insured flood situation I would like to think you'd have bigger issues than 1000 bucks in new non-treated studs to reframe the walls if required.

And as noted earlier, when you pull off all of the wet gyproc it gives it time to dry out.

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