Duct covering identification help

[Matthew Jardine]

Good evening gentlemen,

 

I am having issues identifying this substance on the ducting from an early 1930's era home.  The white tape I know is asbestos and is included in my report but the brown granulated substance I am not familiar with.  It had almost a cork type texture and was on most of the main trunk ducts except where the ducting had been replaced over the years.   I have inspected a few homes in this subdivision and this is the first time I remember seeing it and Google is not helping. Any of you gents have some information you could impart unto me? 

 

Thank you in advance 

[Bill Kibbel]

Hi Mathew,

Look into the Armstrong Cork & Insulation Co. They manufactured many products for industrial processes and almost all of the cork building materials - and there are many.  Duct insulation was one of their products.

I see it occasionally - not real common in residential.

[Les]

Present but also uncommon in Mid-Michigan.  Most that I have seen had traces of asbestos.  Very common in the old auto factory buildings and in the early oil field production machinery.  great question. 

[Matthew Jardine]

Bill - Thanks for the name. That actually makes it much easier. Found an old publication which really opened up the avenues for more research

 

Les- I appreciate it. I've been at this a while and it never ceases to amaze me to learn how much I don't know. Which is why I lurk on this forum as much as possible. 

 

Thank you both for the information! I appreciate it tremendously!