Approx 10mo ago, I bought a large gun safe for my home. Due to limited space, I had to put it in the garage closet. Based on info from forum members and other online sources, I put it a goldenrod and a large desiccant pack (cup with another cup inside to draw in moisture).
Up until now, I have not had one drop of moisture in the safe - checked today and had approx 6-8oz of water in that desiccant cup. It has been very hot and very humid where I live (typical of KY summers) but not that different from the rest of the summer. I probably last checked that cup 4-6wka ago and it was empty. The goldenrod is still on and working and there doesn't appear to be any corrosion on any of the safe items. The only recent change is that the wife and I cleaned the garage out and put several other items in the same closet but I don't know how that would effect items inside a sealed safe.
How concerned should I be about this recent large amount of moisture coming into the safe and what other precautions should I take to keep my guns/knives from rusting?

If the garage slab was cool and then you got warm weather, the interior of the safe might be too cold for the Goldenrod to keep it above the ambient air temperature.

Is the safe in direct contact with the concrete floor?

You'll see then when you use a Goldenrod along with a desiccant.

The rod generates heat which raises the dew point. This warm air will rise and escape out of the top of the door gap. As this occurs outside air will be drawn into the safe through the bottom of the door gap.

Since desiccant captures moisture, and you're drawing in a never ending supply of fresh moist air, you'll find it collects more than were you not using a dry rod and the air was static.

Safe in direct contact with floor.

Have been running the goldenrod since I bought it with no moisture. Maybe a little more Hot and humid lately but it's hot and humid all summer here.

Should I be concerned as long as desiccant is extracting moisture? Do I need to get another desiccant pack? Add other options?

get a carpet remnant and remount the safe on this. you need a temperature barrier from the cement.

Quit using either the dessicant or the Golden Rod. I'd quit the dessicant, myself.

quote:

Originally posted by ChuckFinley:
get a carpet remnant and remount the safe on this. you need a temperature barrier from the cement.

Even better, bolt your safe to the garage floor through a hockey puck in each corner. It'll perform better than the carpet, and since most safe's are unpainted on the bottom it should last longer than on carpet.

^ FTW.
<$6 on Amazon.

quote:

How concerned should I be about this recent large amount of moisture coming into the safe and what other precautions should I take to keep my guns/knives from rusting?

Damned concerned.

Here's a suggestion I'll pitch ya. I have a safe in a basement in the wettest part of the country. Buy a dehumidifier. Here's the thing, some of them will give you a reading of what the humidity is. That's the one you want. It tells you what it currently is and you can simply press a button and adjust it to where you want it to be. (btw, too little moisture ain't necessarily a good thing, ask yer wood rifle stocks when they crack)

Now, there's some caveats I'll add. If your wife chooses to open all the windows on a humid day, all hope is lost:-) Otherwise, it works well. I have a Delongi (which they no longer make) that has been pulling yeomans duty for 7 years. I've learned to work with it. For example, if I know I'm heading to the range tomorrow, I'll go down and crank it down to 45 or so. The thing will pull a gallon of water (as measured, really it's a gallon) then shut down. So If I know I'm going to the range tomorrow and will be opening my safe, I see it's at 60 (which ain't bad) and I'll crank it down, shut the windows, and make sure the reservoir gets emptied before bedtime. They make versions that have a tube which puts the moisture in your drain, but I cheaped out and have to empty it cause I bought a cheap one. Anyway, the thing will work all night and the entire basement is dry when I open the safe to grab my (insert amazing pistol model here) to head out.

I also have the internal desiccant and a goldenrod, I feel they're part of a critical team. That team includes a dehumidifer to dry out all of the rooms air. Anyway, do some research on sizes, models, features etc etc, the things work great. Side note, I have relyed on Consumer Reports for years. However, the last time they recommended this item, as top dawg they choose one that WILL NOT SHUT OFF! I figured mine was going to die and bought the best model they suggested, I think it was the GE: it sucks. Won't shut off and doesn't tell you the humidity. So good luck, let us know what you get.

I would not depend on a carpet remnant, or other membrane. Hockey pucks or other non-metallic spacers to separate the safe from the concrete are key. Concrete can vary in its moisture content depending on your water table, that's a vehicle for moisture certainly. But really it is that the concrete is going to be an ice cube compared to the safe no matter what. Separation with an air gap is key.

The humidity in your region is one factor, and what a1abdj said is correct and part of the issue.

Cold + hot is how you get condensation, and well, metal is really great at being colder than the surrounding air. Making sure your goldenrod is correctly sized for the safe is key, because if it's not heating all the air fast enough, then it is indeed drawing cold air in. The goldenrod needs to be sized to bring the whole safe warmer than the surrounding air. Such that it is near static, and any air drawn into the safe is quickly expunged of moisture.

Step one is going to be getting the safe out of contact with the concrete. Step two will be making sure the safe is not subject to temperature swings.

Garages aren't the best place for safes, for a variety of reasons.

Duct tape the door seams on outside to prevent humidity intrusion

Desiccant inside

Absolutely get that safe off the concrete and provide an air-gap.

Suggest you consider using foam roofing insulation as the thermal barrier between your safe and the concrete floor it's mounted on.

You can get polyisocyanurate roof insulation panels measuring 4'x4' or 4'x8' at any of the big box stores (Lowes, Home Depot, Mynards, etc.) in panels varying from 1/2" thick to 3" thick. It generally has an "R" value of 6 per inch of thickness; in other words if you use 3" thick polyisocyanurate then your safe will have a thermal barrier of ~R=18 between it and your floor.

Polyisocyanurate is non-toxic, it doesn't "gas-off", moisture cannot/doesn't migrate through it, it doesn't crush easily (not great with point loads, but will handle distributed loads of hundreds of pounds/square inch before crushing), and it has a relatively high R value for its thickness.

You can cut the stuff with a pocket knife or a hand saw into any shape you want -- easy to carve out round holes for your hockey puck corner mounts. You can use multiple layers to get the exact thickness for the height of the safe floor and the R value that you want.

As far as a building envelope, polyiso is not recommended for concrete contact, or anywhere it could be exposed to moisture or water. XPS/EPS is now recommended because polyiso acts like a sponge.

As far as sitting a safe on some, either polyiso or xps/eps would be fine. I'd add a piece of masonite to aid in getting the safe onto the foam.

Foam insulation's not a bad idea, but as long as some sort of thermal break exists between concrete and the safe, and you've got a drying rod in the safe, then you're on your way.

From a highly humid and hot region, moisture is a major concern here. A couple of thoughts. I would not recommend having a gun safe in an uninsulated, non-air conditioned space. As suggested I would insulate the room on all six sides, put in a weather tight door, and install at a minimum a dehumidifier. A vapor barrier on the concrete with a platform of 2x4's laid flat with foam insulation between the 2x4's and a plywood deck will get you off the concrete. We have used this as a way to put pine flooring over a concrete floor. If your closet is anywhere near the ductwork or the plenum for your air handler you might be able to run a small AC duct and return air duct into the room without a lot of expense.