# Knob & Tube Wiring and Replacement Insulation



## Robert Ellenberg (Jan 12, 2015)

This question relates to the Building Official's authority to require replacement of knob and tube wiring.

This old house was in close proximity to a major fire and suffered smoke damage.  The insurance company acknowledged lots of cleaning and removal and replacement of insulation in the attic.  The insulation contractors who have seen it won't do the job since the wiring insulation is so old, brittle and fragile (I think there may be some areas of wiring insulation missing now).  Is there authority within the code for the official to require the wiring to be upgraded per code due to the insulation being replaced?  The inspector is an acquaintance who is new on the job in a small town and asked if I'd post the question since I am a Sawhorse member.


----------



## steveray (Jan 12, 2015)

If it truly has become "unsafe" then yes...but not just because it is knob and tube.....it could be repaired in an "approved" manner or replaced....


----------



## cda (Jan 12, 2015)

Insurance company might be able to push it


----------



## steveray (Jan 12, 2015)

I remember Chris Kennedy I think it was that had some really cool knob and tube pics of a commercial install that was still going strong.........


----------



## Pcinspector1 (Jan 12, 2015)

Knob & tube is still allowed to be in use but not if its unsafe, and brittle and fragile insulation would IMO make it unsafe and should be removed.

If there is old brittle and fragile wiring that would be concealed then I think the AHJ can call for it's replacement and the insulation company is doing everyone a favor by bringing it to the homeowners and the AHJ's attention.

NEC 394.12 Uses not permitted, (5) Hollow spaces of walls and ceilings and attics where such spaces are insulated by loose, rolled or foam-in-place insulating material that envelops the conductors. Also see NEC 394.23 Accessible attics

NEC 398 open wiring on insulators, is required to be exposed

AHJ NEC Art 100, Special permission and NEC Art 90.4 Enforcement

pc1


----------



## ICE (Jan 12, 2015)

It would take a pretty hungry electrical contractor to R&R knob and tube.


----------



## Robert Ellenberg (Jan 12, 2015)

Thanks so much for the quick responses


----------



## north star (Jan 12, 2015)

*= \ = \ =*



Robert Ellenberg,

Thanks for coming to this Forum to seek accurate answers.

Not trying to rain on your parade or anything, but technically

speaking, ...you are not a Sawhorse, but rather a Silver

[ level ] member.

We value all participants and contributors on this Forum

and would like for you to continue being an active

participant.

If you would like to become a Sawhorse [ i.e. - a paid

membership ], then consider contributing only $60.00

for a 2 year membership.

The "entertainment value" alone is worth that much !  :mrgreen:

Thanks !

*= / = / =*


----------



## rnapier (Jan 13, 2015)

Remember that Knob and Tube cannot be in insulation.

2014 NEC

394.12 Uses Not Permitted. Concealed knob-and-tube

wiring shall not be used in the following:

(5) Hollow spaces of walls, ceilings, and attics where such spaces are insulated by loose, rolled, or foamed-inplace insulating material that envelops the conductors


----------



## fireguy (Jan 13, 2015)

I am sure the 2014 NEC was not in effect in 1890 when my house was built.  But there was and still may be, programs to replace the knob and tube in residences.  I took advantage of one of those programs many years ago, and got the knob and tube replaced.  I think the interest was less than 2%.


----------



## pwood (Jan 15, 2015)

so the bo goes out and says what he can see looks iffy. The electricial replaces the visible wiring and the house burns down from a suspect electrical fire. Is the inspector and jurisdiction then liable? The fire may be the result of a defective hidden wire or faulty splice with the knob and tube and romex but who gets unceremoniously dragged into court? I would have a licensed electrician give the approval or disapproval to the insurance company and then you get a permit from the ahj to wire and insulate the sfd. BO's don't have the time or the resources to help contractors drum up business. something are better off left to the private sector.


----------



## steveray (Jan 16, 2015)

pwood said:
			
		

> so the bo goes out and says what he can see looks iffy. The electricial replaces the visible wiring and the house burns down from a suspect electrical fire. Is the inspector and jurisdiction then liable? The fire may be the result of a defective hidden wire or faulty splice with the knob and tube and romex but who gets unceremoniously dragged into court? I would have a licensed electrician give the approval or disapproval to the insurance company and then you get a permit from the ahj to wire and insulate the sfd. BO's don't have the time or the resources to help contractors drum up business. something are better off left to the private sector.


BO would only be personally liable if they were negligent...Saw something, did nothing....


----------



## David Henderson (Jan 16, 2015)

Calif. a electrical contractor licensed by the State of Calif. can certify that there that the existing wiring is in good condition with no evidence of deterioration or improper over-current protection, and no improper connections or splices. CEC 394.12 Exception (1)


----------



## ADAguy (Jan 16, 2020)

If he does, can it then be covered with insulation?


----------



## JPohling (Jan 16, 2020)

You would be foolish to cover knob and tube even if code allowed.  One trip into the attic walking around thru insulation I guarantee you will step on hidden wiring and cause some serious damage to the conductors.  I have knob and tube throughout my attic 1914 vintage.  I would only consider placing insulation on the underside of the roof framing, but not on the attic "floor".  I remain un-insulated


----------



## ADAguy (Jan 23, 2020)

Point well made


----------



## ICE (Jan 26, 2020)

steveray said:


> BO would only be personally liable if they were negligent...Saw something, did nothing....


Not in California.  Negligence is allowed. It takes malice aforethought to get a BO in trouble.


----------



## Mark K (Jan 26, 2020)

As stated, in California the building official has essentially no liability.  But if the official or inspector goes beyond the code and takes steps to create a special relationship to "protect" the home owner then the building official or inspector can be liable.  Think about this when you try to enforce a requirement that is not in the building code.


----------



## e hilton (Jan 26, 2020)

Mark K said:


> But if the official or inspector goes beyond the code and takes steps to create a special relationship to "protect" the home owner then the building official or inspector can be liable.  Think about this when you try to enforce a requirement that is not in the building code.


Interesting statement.  So if the inspector tries to protect the HO ... i would assume he was trying to very strictly enforce the intent of the code, as opposed to turning a blind eye to go easy on the contractor.  Only party who would get upset in that situation would be the contractor who was probably cutting corners anyway.


----------

