It was common practice to offset the chimney on one side of a wall say the kitchen for a kitchen wood stove and leave the living room wall flush.
Air space along side of chimney in attic.
It s easy to see your point about eliminating ductwork from the attic.
Construct a sheet metal shield around combustion flues to maintain 3 inches of clearance between the flue and attic insulation.
Make the air move over as long a path as possible.
Then when they got to the attic they made a small correction to make the chimney exit at the ridge.
Access the attic through a crawl space in the ceiling using a stepladder or use or the attic stairs.
Combustible material shall be permitted to abut the masonry chimney walls provided there is a minimum of 12 inches to the inside surface of the flue liner or in the case of a fireplace 12 inches from the inside surface of the firebox.
Right or wrong that s just the way they did it up until 75 to 100 years or so ago.
Heated rooms built into attics often have open cavities in the floor framing under the walls.
A two room addition on the 1st floor has limited attic space and a 4 crawl space.
Plug all open joist spaces under insulated side walls.
Opening all the windows at the same time doesn t do much either.
Windows a few feet apart don t do much.
Try to draw in air from cooler outside areas but note that doing so may not be practical due to prevailing winds.
Fold the bag over and stuff it into the joist space under the wall.
Long piece from a batt of fiberglass insulation and place it at the bottom of a 13 gallon plastic garbage bag.
However i have two questions if i want to centrally air condition my entire house.
With the metal types check with the manufacturer as some are still tested with the loose attic insulation shield firestops and should be left as is.
Ideally both metal and masonry chimneys should be airsealed for energy conservation purposes air leakage and to stop house moisture getting to the attic with the escaping house air.
Measure the four sides of the chimney where it goes through the ceiling framing and add up the.
For exterior chimneys a 1 inch minimum air space must be maintained between the chimney and combustibles.