In ,
nestork typed:
Steve Kraus;3305271 Wrote:

House was built in 1957. Furnace is in a centrally located hall
closet with louvered bi-fold doors. My issue is noise.

Those louvered bifold doors would be a big part of it. They'd stop
next to no noise at all.

If it wuz me I would go to your local Habitat ReStore and buy a few
sheets of plywood that you can cut to the size of opening to cover the
bifold doors. Glue/screw them together and sit that mass of wood in
the opening in front of the bifold doors.

Hopefully, you don't mean to actually block the louvered openings in the
bi-fold doors since his gas-fired heater apparently sits in a hall closet.
It needs enough air intake for good and safe combustion.

Maybe you meant to hang that plywood mass or other barrier between the
heater and the louvered doors as a sound barrier or baffle but without
blocking any of the air flow through the louvered doors and to the heater.

See if that helps. You
can also replace the drywall around the closet with Dow Corning's
QuietZone drywall. There are other drywalls that reduce noise, often
by simply being heavier than normal drywall, since it's primarily
mass that's effective in minimizing noise transmission through walls,
floors and ceilings.

QuietZone, or QuietRock, or whatever it is called is very expensive and way
overrated in my opinion. But the sound barrier/baffle idea that you
mentioned before may work.

Or, at least, I'd focus on containing the noise within the closet as
best you can before you start replacing the furnace cuz of the noise.

I agree.