Basement dehumidification – transfer grille into utility room?
Can a dehumidifier be effective for the whole basement if it’s located inside a drywalled utility room? Assume the utility door is normally closed. Would a transfer grille help significantly?
We have a walk-out basement, close to 1500 sq ft total. Most of it is finished, and there is a utility room that is drywalled. There is a walk-in door to the utility room. I’m considering adding an in-wall dehumidifier (eg, Santa Fe UltraMD33) that would face into the finished basement and allow a gravity drain directly to sump pit.
But, in-wall dehumidifiers are pricey and not likely a lot more robust than any other, maybe a six year lifetime? So I’m considering getting a standard dehumidifier (say, Midea 50 pint Cube) and putting it in the utility room. Which prompted the questions.
Thanks,
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Replies
A dehumifier running in a sealed room won't really help much for the space outside of that room. Simple transfer vents will help, but you really need some moving airflow to even things out over a larger space.
I have a portable-type dehumidifier (I think Midea, actually, but can't remember for sure) in my basement here at home. The first GE unit lasted nearly 20 years. The next unit was an emergency replacement bought at a box store that lasted maybe 4 years. The current unit has been going about 2 years so far, so we'll see how well it holds up. Unfortunately, these dehumidifers are basically disposable units and tend to not last for as long as I'd like them to.
Bill
As Bill says, you need some forced airflow to effectively dry the whole basement. Some dehumidifiers pull air through the front and exhaust out the back. It is relatively easy to frame an opening in a wall so that the dehumidifier sits pretty snug in the opening, and even seal it with flexible foam if necessary/desired. If the mechanical room is a small, closed room, then a transfer grille on the other side of the room allows for a complete circuit of the basement. This is much harder for the upflow style of dehumidifier.
FWIW, the Santa Fe is a very different animal than the typical big-box dehumidifiers. IIRC, it uses a much more efficient technology and better filtration in addition to being designed with duct connections in mind. I would expect 15-20+ years from a Santa Fe unit, much like any other piece of installed HVAC equipment.