[shawnss]

I have a 1950's military house located in Utah and it has been updated with new furnace and ducting, which is not the issue. I am more concerned or curious about a length of ducting approximately 24in by 12in going from the attic to the crawlspace. Nothing is on either end it is just open metal ducting that you can either look down (attic) or look up (crawlspace). There is however a length of gas piping inside of the ducting but I cannot find its source or reason for being in the attic.

Should this be plugged for insulation purposes or does it actually vent the crawlspace for some reason?

Any light on this topic is great.

Thanks

 

[joecaption]

There's 0 reason there needs to be any form of venting from the crawl space to the attic. In fact it's a fire hazard.

 

[jagans]

Sounds like a great chase to pull additional electrical circuits (Bedroom ceiling fans?) in the future, just stuff the bottom with fiberglass Bat in the meantime. :thumbup:

 

[myfirstrodeo]

I agree with joecaption. Many municipalities frown on through-floor openings, as they aid in the spread of smoke in the event that a fire occurs.

If you're planning on plugging the opening you may want to check out the International Firestop Council's website to get some information on what firestopping is all about, and the materials commonly used in an approved system. Also check with your town's code enforcement to help determine exactly what is required for your dwelling.

 

[hvac5646]

Might be an old oil flue from an oil burner in the crawl.

We had a lot of old military housing here and if my memory serves, they were all a uniform standard as the military requires of most everything.