Direct Vent vs Ventless Gas Fireplace

I have a full (very large) basement. It's a finished basement that I plan to use for Sunday Football and family gatherings. I'm looking to put some heat in this space. The only real choice is gas. Ventless will be an easy install but I've been warned about the moisture they can produce. The basement has three rooms and one of the rooms (storage room) gets a very small amount of rain during heavy rain. The rest of the basement can feel a bit moist at times but bathing that ruins furniture or anything. I run a standard dehumidifier just in case and have it draining through a floor drain.

My questions are simple:
1) how much moisture do they produce compared to the vented?
2) can I safely expect a dehumidifier (or a larger/second) to fight the additional humidity?


Thanks guys!

IMO, you want to stay away as far as possible from these things... :hide:

GOOGLE them and you will get plenty of reading.

BTW- I have one and it is of no use, EXCEPT TO STINK UP THE HOUSE AND GIVE YOU HEADACHES.

How hard is it to have direct vent.

I would go direct vent if at all possible. They will do a very good job of heating the space. Direct vents will bring in outside air for combustion as well. If your location is on an outside wall going direct vent shouldn't be difficult.

Slippery95 said:

I have a full (very large) basement. It's a finished basement that I plan to use for Sunday Football and family gatherings. I'm looking to put some heat in this space. The only real choice is gas. Ventless will be an easy install but I've been warned about the moisture they can produce. The basement has three rooms and one of the rooms (storage room) gets a very small amount of rain during heavy rain. The rest of the basement can feel a bit moist at times but bathing that ruins furniture or anything. I run a standard dehumidifier just in case and have it draining through a floor drain.

My questions are simple:
1) how much moisture do they produce compared to the vented?
2) can I safely expect a dehumidifier (or a larger/second) to fight the additional humidity?


Thanks guys!

Click to expand...

I’m assuming you have some sort of gas furnace now to heat the upstairs. You said you have a finished basement. Is that something you did yourself and wasn’t heating addressed when the basement was finished?

I would look into extending the heating source you have for the main floor to help with the basement. Our house the basement is unfinished and was quite cool in the winter months and with working down there I wanted some heat. I just cut a hole in the main hot air supply plenum and installed a grate that can be closed. I have it open a little all winter and it lets just a little warm air enter the basement and I assume enough air finds its way back upstairs as makeup air. Maybe you can cut into a couple of the supplies in the area you want heat and let your furnace do the job.

If you have hot water heat just add a zone with baseboard heaters.

If none of the above work we set my nephews house up with gas hot water heat using a domestic hot water tank as the source and a small circulating pump and baseboards with a Tstat controlling the pump. The heat is fantastic.

I’m not a big fan of the unvented for heat in a living area and unless you are going for the fireplace look it’s much easier to get gas into heat other ways IMO.