I am finishing the gunroom in my new house. Concrete room outside the foundation of the basement with plastic, insulation, studded walls and finished drywall on ceiling and walls. The floor is linoleum and gun racks/cabinets are finished cherry whcih are almost ready to install. I ran a heating duct through the concrete along with a cold air return and wired the room for lights. The door is a comercial steel vault door salvaged from a 100 year old local bank.
Last night I bought a humidity gauge and this morning read 54%. I was surprised as the basement always has been dry. The gauge did sit on the floor as I haven't quite finished the cabinetry yet.
What should the level of humidity be in my room to protect the guns from rust?

40 to 45 % is ideal. Any drier and your recoil pads will harden faster than normal.

I know your dilemma. Mine ran 90% for a while until I put a ceramic heater in there. My set up is almost identical to yours. I finally got it down to 15% but right now it is staying around 45%. I hope this is good because it looks like its the best I can maintain.
Doug

Normal humidity is just fine. What you don't want is the guns being colder than the air that comes in.

So run some kind of heat in there all of the time. I am not sure how much for an entire room but 4W is enough for a safe. I am guessing that a 40 W bulb will do it but I defer to experts.

Since the room has been sealed up, humidity has been between 36 adn 46%. And always around 36% when I come in there so I think the longer it's closed, the dryer it gets. I did buy some silica gel pacs from gander mountain which should gather any moisture just in case. Room is quite confortable at around 66 degree's with the heat blowing through the room.

Shane,
Sears has a 20 quart de humidifier and it has worked for years in my vault. Plug it in and turn it to the setting you want. You will have to dump the water now and then if you do not have a direct dump into sewer or outside.
Mine has been in there 18 years.
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