# sealing gap around furnace flue in attic



## jklingel (Dec 21, 2008)

did you ever look into using roxul around that gaping hole? it sure looks like a ton of heat will be running up there, as well as water vapor. not a problem in your case? just a thought.


----------



## Windows on Wash (Aug 30, 2011)

Good follow up.

You would be amazed at how some of these chases are constructed. You could put Jimmy Hoffa in some of these things.


----------



## old_squid (Oct 31, 2012)

They're called a chimney in a chimney. 


Just kidding. But it is how they function especially if there is an air passage way from the home/basement directly to the attic.


----------



## Gary in WA (Mar 11, 2009)

Good you used metal for an air barrier as Roxul, fiberglass, cellulose or other fibrous cavity insulation types are not air-tight or meet minimum code in this application. You could improve slightly on your design by over-lapping one side metal piece for an area to lay the caulking bead on- catching both surfaces/sides for optimum contact just by shifting one metal onto the other when drawing the pattern circle. Now, get back up there again! Just kidding........ Good job!
http://www.buildingscience.com/documents/insights/bsi-035-we-need-to-do-it-different-this-time

Gary


----------



## Dave Sal (Dec 20, 2012)

Actually Gary, I did cut a piece of sheet metal that overlapped on each other, but I didn't take a picture of it. The pic of the sheet metal flashing was my first version before I realized I needed to have it overlap. 

I am going to add Roxul to the chase opening in the utility room and then seal it with more sheet metal between the joists. It'll be much easier getting access to it and should stop the majority of heated air from rising to the attic. It snowed here last week and most homes have snow covered roofs. But, driving around looking at roofs and it's amazing to see how many have absolutely no snow on them after completely melting. The large icicles on the gutters are another indicator that these homes lack adequate insulation or attic venting. Fortunately, my roof is still nice and snow covered. :thumbsup:

My latest energy saving project was making an insulated fireplace insert to block the cold drafts coming into the family room. I installed it the other day and I can actually feel the difference. The room used to be chilly all the time as it is below grade, but now it's noticeably warmer and the chill is gone. I still need to sand and stain it but may wait till spring so I don't have to smell the off-gassing from the stain. Now I need to come up with a new project to keep myself busy.


----------



## Gary in WA (Mar 11, 2009)

You have to be careful around here when posting pictures.... lol. You passed the snow test= *A+* you may now advance to more adventurous projects!

Later, Gary


----------

