Concrobium And Knob And Tube Wiring - Electrical - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 02-24-2011, 09:31 AM   #1
I ask the impossible!
 
Join Date: Aug 2010
Location: Royal Oak, Michigan
Posts: 1,074
Rewards Points: 508
Blog Entries: 7
Default

Concrobium and knob and tube wiring


So I have an apparent mold problem that I detected by shoving a digital camera with flash into a floor cavity I can access from the side attic only, this is a floor cavity which has drywall on the bottom, floor joists on the side and subfloor on the top, so I can access it from the openning at the side wall. I will be treating this mold problem by fogging Concrobium Mold Control into the area.

My concern is that these joist cavities also contain live knob and tube wiring. The company has EPA and Health Canada regulatory approvals, and they indicate that the spray is non-corosive, but their FAQ does not adress contact with knob and tube wiring and a phone call to the company did not adequately satisfy my concerns. Had there been some sort of UL certification I might have been satisfied.

In my mind, this is effectively a salt spray. Contact with live electrical wiring seems like it could risk causing a short, arcing and potentially a fire.

Does anybody have any actual experience on this?

I do not have any way to cover the wiring, if this is an issue I would have to leave any cavities with knob and tube untreated until I am able to open those cavities to protect knob and tube, and/or until I am able to update the knob and tube wiring. I may actually do this anyway, I don't specifically know that the cavities that have knob and tube also have mold problems, but I would prefer to treat all floor cavities.

Advertisement

WillK is offline   Reply With Quote
Old 02-24-2011, 02:43 PM   #2
Scared Electrician
 
Saturday Cowboy's Avatar
 
Join Date: Nov 2009
Location: Colorado
Posts: 715
Rewards Points: 500
Default

Concrobium and knob and tube wiring


I don't think you will find anyone who can answer this question. K&T is safe but begins to fail quickly if disturbed. I don't think anyone(including manufacture) has tested that.

Advertisement

__________________
Ragged Trousered Philanthropist


Please follow the code - its there for your safety no matter how inconvenient.
Saturday Cowboy is offline   Reply With Quote
Old 02-24-2011, 03:13 PM   #3
nap
You talking to me?
 
nap's Avatar
 
Join Date: Dec 2007
Location: sw mi
Posts: 5,407
Rewards Points: 2,000
Default

Concrobium and knob and tube wiring


you need to speak to the Concrobium folks directly about the concerns. I suspect they will say something like "it is safe to use on any wiring that is in good condition".

what that means is:

we aren't going to define "good condition" and if you have a problem and the wiring is anything other than brand new wiring, it was likely not in "good condition".


Unless you can get them to commit to the safety given the specific concern, I would tend to be very leery of using it.

.
Quote:
The company has EPA and Health Canada regulatory approvals, and they indicate that the spray is non-corosive,
Quote:
In my mind, this is effectively a salt spray
there is a serious inconsistency concerning those two statements.
nap is offline   Reply With Quote
Old 02-24-2011, 10:00 PM   #4
I ask the impossible!
 
Join Date: Aug 2010
Location: Royal Oak, Michigan
Posts: 1,074
Rewards Points: 508
Blog Entries: 7
Default

Concrobium and knob and tube wiring


Well, I think that a) that's why I came here to ask that (I had spoken with Concrobium's customer service before posting here and not gotten a definitive yea or nay) and b) I think that was my gut feeling, and I just wanted to see if it was valid.

Ya know what, I have to clarify that one step further too. The representative I spoke with was not even familiar with what I meant by knob and tube wiring.

I've been an engineer in an industry where FDA (and Health Canada too for that matter, now that I think of it) approval of medical devices is involved, so I can read between the lines of their claims that they have EPA and Health Canada approval. It means it's safe to breathe the stuff when sprayed. It means nothing in the context of anything like NEC or NFPA.

And I also understand their unwillingness to say that their product is unsafe. It's more than just wanting to not lose my business, it's also a potential liability if they have a danger they admit to knowing that is not included in their product labelling. They have their generic blanket statements of don't use this if you have doubts, paraphrased.

Maybe I'll try an experiment some time for my own curiousity.

Last edited by WillK; 02-24-2011 at 10:03 PM.
WillK is offline   Reply With Quote
Old 02-24-2011, 10:06 PM   #5
Scared Electrician
 
Saturday Cowboy's Avatar
 
Join Date: Nov 2009
Location: Colorado
Posts: 715
Rewards Points: 500
Default

Concrobium and knob and tube wiring


Quote:
Originally Posted by WillK View Post
The representative I spoke with was not even familiar with what I meant by knob and tube wiring.
__________________
Ragged Trousered Philanthropist


Please follow the code - its there for your safety no matter how inconvenient.
Saturday Cowboy is offline   Reply With Quote
Old 02-24-2011, 10:33 PM   #6
Member
 
Join Date: Feb 2011
Posts: 66
Rewards Points: 75
Default

Concrobium and knob and tube wiring


I would replace any knob and tube wiring it is seriously out of date. Also if it is non corrosive I would turn the electricity off and allow it to dry thoroughly before reenergizing. If it doesn't deteriorate the wiring it should be fine.
Jj375 is offline   Reply With Quote
Old 02-24-2011, 10:49 PM   #7
I ask the impossible!
 
Join Date: Aug 2010
Location: Royal Oak, Michigan
Posts: 1,074
Rewards Points: 508
Blog Entries: 7
Default

Concrobium and knob and tube wiring


At this point, live knob and tube wiring is down to a few ceiling lights in rooms that are not getting gutted at this time. The stuff that is left is very difficult to access, so I've drawn a line as far as how much electrical work I am doing at this point and I have MUCH more serious issues that I'm tackling first. The mold problem was identified as part of my own more detailed assessment of the structural issues I'm dealing with after I deal with structural issues I'm dealing with now. (Currently working on structure under the first floor, which will be followed by sagging of the second floor.)
WillK is offline   Reply With Quote
Old 02-25-2011, 06:55 AM   #8
Member
 
Join Date: Feb 2011
Location: SE Mass
Posts: 87
Rewards Points: 75
Default

Concrobium and knob and tube wiring


Quote:
Originally Posted by Jj375 View Post
I would replace any knob and tube wiring it is seriously out of date. Also if it is non corrosive I would turn the electricity off and allow it to dry thoroughly before reenergizing. If it doesn't deteriorate the wiring it should be fine.
X2

Your K & T will be fine...for now.
Do It Right is offline   Reply With Quote
Old 02-26-2011, 10:44 PM   #9
Newbie
 
Join Date: Feb 2011
Posts: 1
Rewards Points: 10
Default

Concrobium and knob and tube wiring


Hello, we've come across this online discussion and would like to provide some points of clarification and additional information about Concrobium Mold Control. If the Concrobium customer who initiated the thread would like to contact us to discuss the matter further, we're happy to do so and are available at 1-866-811-4148.

First, we need to point out that the product's Health Canada and EPA registrations relate solely to product efficacy - i.e. the product's mold-fighting qualities.

While the product is non-toxic and contains no harmful chemicals, it would be irresponsible of us to unconditionally advise that the product can be fogged in the environment that's been described. The advice of an electrician would provide the most useful perspective on whether a water-based solution can be safely fogged in the area.

Please find below two considerations that might help with the decision:
1) As with most cleaning solutions, the product is over 95% water, so if the electrician felt that misting water into the area was completely safe it is likely that doing so with Concrobium would be safe.
2) Concrobium Mold Control contains three compounds from the salt family, in very low concentrations. To work, the product needs to dry on the surface, and ideally remain on the surface to provide continual mold protection. There must be a comfort level that such a solution can remain on the exposed knob and tube wiring to go forward with the project.

Again, we are happy to provide more information, including the specific ingredients of the product, if you would like to contact us to further discuss.

Sincerely,
The Planet People Team
Planet People is offline   Reply With Quote
Old 02-27-2011, 11:23 PM   #10
nap
You talking to me?
 
nap's Avatar
 
Join Date: Dec 2007
Location: sw mi
Posts: 5,407
Rewards Points: 2,000
Default

Concrobium and knob and tube wiring


Quote:
Planet People;598763]

While the product is non-toxic and contains no harmful chemicals, it would be irresponsible of us to unconditionally advise that the product can be fogged in the environment that's been described. The advice of an electrician would provide the most useful perspective on whether a water-based solution can be safely fogged in the area.
they have had an electrician comment. At least one

An electrician is not qualified to determine if your chemicals are detrimental to the wire or insulation. That is something you folks should be able to answer given it is your product and you are the folks that would need the UL listing or approval from whomever.

Personally, if a manufacturer or distributor cannot address the use of their product to a specific situation, I would tend to shy away from it. Not saying they are going to know what happens in every situation, just that if this is one they cannot address, it would likely be best to not be the guinea pig.
nap is offline   Reply With Quote
Old 02-28-2011, 02:03 AM   #11
Member
 
Join Date: Nov 2010
Posts: 73
Rewards Points: 75
Default

Concrobium and knob and tube wiring


I think when my house was built homes weren't wired. Although the attic had an intricate layout of K&T when I bought it, the lightswitch and outlet wiring had just been fished into place and not secured. It was trivial to use the old wiring to pull new in place. I think I "re-wired" the place in about 2 days.

I think the concrobium people's response here was good. I doubt even UL has a relevant testing procedure, although you may be able to find something about salt spray and K&T in old literature. Even across installs of K&T I'd expect a huge variation on their sensitivity to water or salt spray depending on age, installation techniques, and environmental factors.

The MSDS for the mold spray might offer some insight, even if the ingredients are proprietary it should give you an idea of the concentration.

At least concrobium bothered to respond. These days when it comes to customer service you have to count your blessings. (Am I mixing metaphors?)

-Jeff
mysterylectric is offline   Reply With Quote
Old 02-28-2011, 09:31 AM   #12
I ask the impossible!
 
Join Date: Aug 2010
Location: Royal Oak, Michigan
Posts: 1,074
Rewards Points: 508
Blog Entries: 7
Default

Concrobium and knob and tube wiring


I agree, it's cool to see the Concrobium people active with internet discussion.

I think I see their point, but at the same time I think I see where asking an electrician directly if exposing K&T to Concrobium is probably not likely to be very productive.

As far as UL... I guess I can see where UL comes in more likely in the case of the equipment that could potentially be sprayed rather than the spray itself.

So with that said, it SOUNDS to me like the question to pose would be whether spraying Concrobium is equivalent to temporarily turning the area sprayed into a damp envioronment, and whether K&T is acceptable for damp environments? 2 part question I guess... And then I would assume that a gray area comes into play because you wonder if it's possible to over-apply the spray, and if you did that does it become a wet location? And I assume K&T is probably not rated for wet locations..

For the electricians part, I presume that an electrician would point to table 310.13 in NEC... My question is where is K&T on that table?
WillK is offline   Reply With Quote
Old 02-28-2011, 11:49 AM   #13
nap
You talking to me?
 
nap's Avatar
 
Join Date: Dec 2007
Location: sw mi
Posts: 5,407
Rewards Points: 2,000
Default

Concrobium and knob and tube wiring


Quote:
Originally Posted by WillK View Post
For the electricians part, I presume that an electrician would point to table 310.13 in NEC... My question is where is K&T on that table?
you can point to whatever you want but the chemicals involved is something the manufacturer either determines it is appropriate for a particular use or not or they don't know.

If they don't know, nobody else is qualified to make that determination. The manufacturer knows what is in their product, not the electrician you are asking to make the decision as to whether some particular type of wire is ok to be exposed to some unkown chemicals.

UL listings: they do all sorts of things, including exactly what we are discussing here. UL does much more that deal with equipment. As an example; they list fire rated wall assemblies and how to deal with penetrations of those assemblies to restore the UL rating. They are a test lab. They test anything somebody wants to have "approved" or "listed" for whatever use is being considered. How a chemical reacts with some particular type of wire would be one such listing.

to the wet or damp; the rating for any particular type of wire is only going to be good while the wire is in good condition. Due to the age and likely degradation, even if it was rated for damp locations, more than likely, it isn't now.
nap is offline   Reply With Quote
Old 02-28-2011, 01:17 PM   #14
I ask the impossible!
 
Join Date: Aug 2010
Location: Royal Oak, Michigan
Posts: 1,074
Rewards Points: 508
Blog Entries: 7
Default

Concrobium and knob and tube wiring


That being the case, I would think that it's easy to say that knob and tube is likely enough to be deteriorated. (I guess that would be a field modification in UL's eyes) Thus if that means it is a risk in a damp location, then that should be enough to advise against a fogging of any water based product.

(for those of you who may not be engineers, it would seem that engineers and those of like mind find this sort of discussion enjoyable... Even though we already reached the same conclusion a week ago.)

Advertisement

WillK is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Top of Page | View New Posts