Re: Observation Hive with vertical 20-25ft exit tube?
My suggestion is to just cut the hole in the wall and be done with it. If you are concerned about how to patch the hole when the OH is eventually removed, just disguise it as something else. You could make the hole suitable such that a dryer vent housing fits the hole. Once the OH is removed, plug the hole and mount the dryer vent exterior housing to disguise the hole.
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