Baloon framed - K&T - UFFI

[John Dirks Jr]

Did a 1940 structure that still had some active K&T. The home had also been retrofitted with UFFI in the exterior walls. A ton of it had spilled into the crawl space and cured in a huge mound. Seriously, a pile the size of a big sow.

Since I saw live K&T coming up from the exterior wall and into the attic, is it a valid concern that UFFI may be encasing K&T somewhere in the exterior walls?

I thought K&T was no longer being used by 1940. It was still in this house.

[John Kogel]

K&T was used into the 50's in my area.

Old timers had garages full of old stuff and were slow to change their ways, maybe?

Also, as you know, the actual date of construction can be off sometimes by a decade or so, especially if the paperwork was lost.

Yes, I would be recommending rewiring all the K&T circuits, because of deteriorating rubber insulation on the wire. They don't have to cut out the old wire, just pull in new cable and install new boxes.

[John Dirks Jr]

I was wondering if the retrofitting of uffi could increase the concern of K&T.

[Jim Port]

I am not familiar with the UFFI, but it sounds like expanding foam insulation. The NEC states that thermal insulation shall not be used with K&T.

[Marc]

One issue with K&T is that the connections go bad with time. Bad connections heat up so you don't want to insulate the stuff because temperatures will reach ignition values more quickly. UFFI burns, doesn't it? We don't have that stuff here.

I'd absolutely write it. Major finding.

Marc

[John Kogel]

PS, balloon framing sounds too old for 1940.