Starting to mold

[35mastr]

Its been pretty cold here latley and my steel roof in the shop is always sweating. So now I have mold growing in the shop on the two peak walls.

The ceiling is always so wet in there that it drips onto everything.
Now if I insulate it will this water be trapped in there all the time? Will it cause the metal to start to rot?

Also how will i be able to attack insulating this celing. They are 2 1/4 metal supports.

This is my Shop
I want to get a handle on this before it gets totally out of hand.

I have no heat in there and it is currently not insulated.

 

[cheap bastard]

Do you have any ventilation for the roof? The thread pics look show none. A vent in each end wall with a fan in one would help.

 

[35mastr]

It had this ceiling dripping issue when it was just the carport with no siding.
I thought closing it in would stop this. But it did not.

 

[ToolLover]

Your problem is inherrant with a metal structure.
I had a "Lane Clear span" metal 40x 70 building.
There is only one way to solve the sweating.
Have a contractor spray foam insulation inside it.
Believe you me it will rain in that building until you do so.

 

[ambenz]

I would spray foam the wall and ceiling and make like a huge beverage cooler!
...adding a dehumidifier might help.

 

[35mastr]

Your problem is inherrant with a metal structure.
I had a "Lane Clear span" metal 40x 70 building.
There is only one way to solve the sweating.
Have a contractor spray foam insulation inside it.
Believe you me it will rain in that building until you do so.

You are correct with the raining issue. Thats exactly what it does every time I open the door.
Would 2 or 3 inch foam board work also.
Any idea of what this spray foam would cost to do a 16x24 building?

 

[ToolLover]

35mastr,
There are new innovations in insulation today.
Watching 2 new houses go up that are going to be green houses (Ultra insulated and sealed) I have seen a lot of new insulation ideas.
I bet it is not as expensive as you would think.
To be sure, it will be well worth it in the long run...especially if you stay there for many years.
Go for it.

 

[5lima30]

I had a metal garage at my last house and it did the same thing. The spray insulation was crazy expensive and messy so I put in gable vents and a fan. It was about 95% effective w/o insulation. Much more comfortable in the summer. YMMV.

 

[nehog]

My questions are:

1. Do you know where the water is coming from? If an unvented heater, can you switch to a vented one?

2. Is the shop heated? If yes, considered a de-humidifier? That's what I have in my shop, and the few times (bless my unvented gas heater...) I've needed it, it worked well.

 

[35mastr]

My questions are:

1. Do you know where the water is coming from? If an unvented heater, can you switch to a vented one?
The water is just condensating on the metal roof inside from the cold weather. No heat in the shop.

2. Is the shop heated? If yes, considered a de-humidifier? That's what I have in my shop, and the few times (bless my unvented gas heater...) I've needed it, it worked well.

No heat,But if a dehumidifier would take care of 90% of the issue I would try it. Any info on the one you may be using?

 

[rickycobra]

Mold is a big problem is their anyway to stop the leaking first.

 

[bazzateer]

Sort the ventilation.
Insulate including a vapour barrier (this will keep the warm air from reaching the steel roof and condensing on it).
Install heating and a de-humidifier.

 

[Weedwaka]

You can't use foam boards in place of the spray in foam.

The spray in needs to adhere directly to the sheeting to prevent the condensation. The foam needs to be closed cell so as to prevent the warmer moist air from coming in contact with the cooler metal. If you use any other type of solution, vapor barrier etc, you better really sort out your ventilation first because that humidity can get in behind and destroy everything you put up.

 

[35mastr]

Mold is a big problem is their anyway to stop the leaking first.

There is no leak. This is just condensating moisture within the building.

 

[Vicegrip]

In addition to expelling the humidity that is gathering at the ceiling you might want to add some fan(s), good ones, blowing up at the ceiling. Air pressure and movement will dry the ceiling even if the metal temp is below dew point. If it ices up the fans will turn the ice to vapor without passing into the water state.

Are you driving warm wet trucks or cars into the garage? Is it warm humid air from day time conditions condensing at night? If the daytime conditions the fans are better than ventilation. If it is from cars or trucks ventilation will work well.

Just looked at your shop build. I would add a $20 box fan at each end of the shop blowing air at the celling and walls. Angle them to cause a churn of air movement.

 

[trbomax]

Since you had the problem when it was a carport,I think the moisture may be comming from the floor.Does it condense too? Is there a vapor barrier under the slab ? Water vapor will come thru concrete.Whats the substrate like? Well drained? any kind of footing or rat wall? Without one ,surface water will get under the floor,temp changes will pull it thru.

 

[35mastr]

Any one that is running a stand alone de-humidifyer want to recommend one that will work in a 16x24 building. Its only 11 feet high.

That is what I am going to need to do until I can find me a company to insulate it.

I am going to try the fans also to see if it will help.

 

[trbomax]

I have 2 of them in the wifes shop.Get the 32 pint LOW TEMP units,the normal ones will freeze up when the ambient temp gets below 55 degrees.We have them set on 35% and empty them about once a week in the winter,more often in summer unless we are running the ac.

 

[35mastr]

I have 2 of them in the wifes shop.Get the 32 pint LOW TEMP units,the normal ones will freeze up when the ambient temp gets below 55 degrees.We have them set on 35% and empty them about once a week in the winter,more often in summer unless we are running the ac.

What brand do you have and a model number? Where did you get them at?
This is all new to me as I have never had the need for these.

 

[Vicegrip]

is the space good and air tight? If not the dehumidifiers will pull moisture out but it will be promptly replaced with new incoming air. This will only eat up electricity. They work best in tight spaces.

 

[35mastr]

is the space good and air tight? If not the dehumidifiers will pull moisture out but it will be promptly replaced with new incoming air. This will only eat up electricity. They work best in tight spaces.

Its all closed in.

 

[trbomax]

What brand do you have and a model number? Where did you get them at?
This is all new to me as I have never had the need for these.

I have the LD mod lhd45el. I was looking at the manuals and they are 45 pint,operate down to 42 degrees. The regular ones only work above 65 degrees.I got them at either lowes or HD,cant remember,they are 3 yrs old now.You can put a drain hose on them,but I did that once and you tend to ignore the unit ,the hose plugs up and overflows all over. We shut them down when we are there because they are a bit noisey

 

[StanLee3058]

Two years ago, I built a 36' X 40' pole barn. I had it built with a metal roof and metal siding. I also put a metal ceiling put in. The walls were studded with 2X6's on 24" centers.
Before I poured the cement floor, I put down a plastic vapor barrier.
I had the walls sprayed with closed cell foam.
After spraying the foam, the whole garage was pretty airtight, except for any air infiltration around the garage doors.
I put up ½" plywood on the walls, primed the plywood with Kilz, and put a coat of latex paint on.
Last summer was the first summer since I had the walls insulated with the spray foam. I was so happy because it could be 85°F outside and it would be 68-70°F inside. Then I noticed little green specks of mold forming on walls in various spots. The mold would brush right off, but it was mold none the less.
According to the guy who sprayed the insulation, my problem was two-fold.
First, he said, the moisture was coming out of the newly poured cement floor. He said it would take 2-3 years for all the moisture to come out of the floor and that the vapor barrier I put down will only allow the moisture to go up. Made sense to me. Secondly, he said, the temperature in the garage, on very humid days, was below the dew point and any moisture in the air would condense out. Again, this made sense.
He then said the green mold was froming on specks of dust and that is why the mold wipes off.
To stop condensation, you need to raise the temperature above the dewpoint. In my case, I don't have any vents, so my only other option is a dehumidifier. Once the cement floor is dry, the moisture problem should subside. I hope. Sorry for the rant. This was/is my experience with mold.

 

[35mastr]

My floor was poured in 2003. So its not the floor. I dont think the floor is going to be your issue either. Its the moisture in the air thats trapped in there causing the whole place to sweat. Then causing the mold issue that both of us have. Specs on everything.

 

[Kevin54]

Ditto on the spray foam to correct it. It needs to seal up against the metal to insulate it. Foam board or any other type of insulation won't do that. Also running a dehumidifier, in my opinion will not stop the problem unless you have a very huge one. When the metal it colder than the inside air you are going to get condensation. Look at it just like a terrarium. You need to get the metal vs. inside air insulated from on another. I bet on really damp days, like when it's humid foggy out, you probably need an umbrella in there

 

[A Crofoot]

I had my roof spray foamed on my shop 2 years ago. My building is 48x65 and it cost $6000. This was in Kansas and had a couple of other quotes that were in the same ballpark. Not sure what the cost is where you are. It made a huge diff! Not only does it stop the water issues but it is so quiet now when it rains. Used to sound like hail when it would rain and was so loud you couldn't hardly work in there if it was raining hard. The shop is an old block building that was always bitter cold before I insulated the roof. Since I sprayed the roof the building has never frozen inside even during spells of several weeks of below freezing temps.

 

[35mastr]

If 2 inch foam board was put up right against the metal roof panels,seams masked and then a heavy mil poly over that to seal it all up. I dont see why that would not work.

I would love to have it sprayed,But I think the cost is going to be alot more than I can aford.

 

[stingry]

Try this. I assume that you have self-storage complexes in your area. Go visit one of them and see what they do to keep condensation from forming. I own several here in Western Nebraska and all we do here is to stretch 4' wide rolled insulation over the purlins and attach the steel roof sheeting over that. This keeps any condensation from forming and dripping onto the stored items in the storage unit. We have a dry climate here so something else may be necessary in a more humid area such as yours. Whatever works in self-storage units will surely work for you. They are just sheet metal boxes.

Good Luck
Steve

 

[35mastr]

Try this. I assume that you have self-storage complexes in your area. Go visit one of them and see what they do to keep condensation from forming. I own several here in Western Nebraska and all we do here is to stretch 4' wide rolled insulation over the purlins and attach the steel roof sheeting over that. This keeps any condensation from forming and dripping onto the stored items in the storage unit. We have a dry climate here so something else may be necessary in a more humid area such as yours. Whatever works in self-storage units will surely work for you. They are just sheet metal boxes.

Good Luck
Steve

Got any pics. Cant really get a visual on what this insulation is. Our climate is dry just like yours. Humidity is pretty low here.

 

[mmhouse]

Just a thin coat of spray-in insulation should resolve the sweating problem. If you needed more insulation you could do something else in addition to it.

Ventilation would certainly help but may not completely solve the problem. It would make sense to try as the first step though.

 

[stingry]

Got any pics. Cant really get a visual on what this insulation is. Our climate is dry just like yours. Humidity is pretty low here.

Don't have a picture but will attempt to describe. The insulation comes in rolls 4 ft wide. It is about 3/4 to 1 inch thick and has a vinyl/plastic sheeting on both sides with some type of insulating material in between. It is very pliable, kind like a big ole thick blanket. In your case, it would be stretched lengthwise over the hoops in which your roof sheeting is attached to. Then the roof sheeting would be placed over the insulation and screwed to the hoops. Seems to work quite well, have had no problems with condensation or mold.

Cheers
Steve

 

[larry_g]

Got any pics. Cant really get a visual on what this insulation is. Our climate is dry just like yours. Humidity is pretty low here.

If you look through my build thread below you will see the 'insulated vapor barier' that we use here. The issue you will have with IVB is that it is sandwiched between the frame and skin of the building. Are you up to removing your roofing and then reinstalling it?

lg
no neat sig line

 

[Crazy Car Guy]

If 2 inch foam board was put up right against the metal roof panels,seams masked and then a heavy mil poly over that to seal it all up. I dont see why that would not work.

I would love to have it sprayed,But I think the cost is going to be alot more than I can aford.

do your 2" foam with a 1/4" gap fill that gap with the cans of expanding foam works like a charm helps hold it in place and is air tight for life no re taping ever
i used it in my temporary shop so i could easily salvage the board when i tear it down and i have had no problems with moisture issues.

 

[long handles]

You could probably use a spray foam kit and DIY it. The two components come in cylinders and it has the gun and all you need to apply it in the kit.

I've seen them at the local lumber yard for $300 and change. It wasn't a box store but they probably have them to.

You could probably google spray foam kit to see what I'm taking about.

Ken

 

[rwhite692]

George, I really would try the dehumidifier first. As long as your space is sealed up well, you won't need a huge one, and it will be very effective. I would get one that has a tank with a drain fitting on the bottom, and connect up a length of 1/4" poly line and run it outside, that way you won't have to be emptying the thing all the time. If you find one without a drain, it would be very easy to make the necessary modifications...

As you know, most of the year, we are very dry here. So you will probably only need to run it during the wettest portion of our rainy season.

 

[35mastr]

If you look through my build thread below you will see the 'insulated vapor barier' that we use here. The issue you will have with IVB is that it is sandwiched between the frame and skin of the building. Are you up to removing your roofing and then reinstalling it?

lg
no neat sig line

Larry,I checked it out. What did they do with the seams? Also I have never seen double plastic faced inso. Where can that be bought?

 

[35mastr]

George, I really would try the dehumidifier first. As long as your space is sealed up well, you won't need a huge one, and it will be very effective. I would get one that has a tank with a drain fitting on the bottom, and connect up a length of 1/4" poly line and run it outside, that way you won't have to be emptying the thing all the time. If you find one without a drain, it would be very easy to make the necessary modifications...

As you know, most of the year, we are very dry here. So you will probably only need to run it during the wettest portion of our rainy season.

I am going to get one. May need to buy one online. I have been running a 18 inch Patten fan in there and it dried it out and keeps it dry. I seem to only have this issue in just cold weather. I have been to most of the local stores and they do not stock them around here.

I just want to get a handle on this before it gets out of control.