There is a passive vent between the first and second level of my ~100 year old house.
There is a removable metal register on the floor of the second level and a removable metal grill attached to the ceiling on the first level.
The dimensions of the vent hole is 12 1/2 x 14 1/2 and 9 1/4 in depth (the "dead space" between the first and second level)
The "dead space" between the levels was "walled in" by 2 L-shaped pieces of metal that could adjust for the specific height of the "dead space". The height adjustment was held in place by 2 springs which attached to the register. There is also a metal lip that is part of this that helps keep it secure with nails.
Most of the metal has rotted away so the dead space between floors is exposed. It is to far done to do anything with.
I am looking for something similar that could replace it. I am fairly certain that this was not a "one off creation" by whoever installed the modern hvac system in the house. This was the ideal solution. It did not leave any gaps at all.
Boxing it in with wood will not work.
I have searched but not some up with anything. I hope by description accurately described what I am looking for.
Anyone have any ideas?
Thank you in advance.