help with ceiling condensation please

[theLumberjack]

So i have a new area set up.
I have 2 4*4 tens inside of a 9*9 insulated room.

the 9*9 room is built inside of an uninsulated detached garage in the mountains of colorado.

As we have gotten these low temp nights regularly I have started to get excessive humidity throughout the garage. I noticed some condensation on the outside of the room originally and was not concerned. However I am now getting drips on the ceiling.

This is where I am concerned. I do not want to ruin my garage or the other things I have stored there.

I put a whole house dehumidifier in there and it hasnt seemed to help much.

I only pull cold air into the 9*9 room and dont exhaust it. I exhaust the tents into the 9*9 room as well to regulate the temperature.

Any ideas? Should I open the window? exhaust some heat directly outside? Not worry about a small bit of condensation? It will go away once it warms..... sorry for the run out, but any ideas is greatly appreciated.

More specific details on the room.

framed floating walls. 2" foam walls and ceiling. extra fiberglass on ceiling. 4" vortex fan pushing garage air into the room on thermostat. keeping the room at 68. each tent is hooked to a 6" max can fan and a can 33. Those exhaust the tents into the 9*9 room based on the thermostats inside each tent. each tent has 2. 315 ceramics. top drip coco on short cycle timer. drain to waste through a flood tray.

 

[theLumberjack]

I am also a bit concerned because the garage amps are nearly full. so running a ton of fans is not an option.
I did read about making a dehumidifier by placing 2 buckets inside of each other. top bucket filled with salt and holes drilled in the bottom. Im tempted to go get 300lbs of salt and 12 buckets...

 

[mowood3479]

Exhaust heat from the 9'x9' room directly outside at a slightly downward angle (so water can run).. Use insulated ducting.
That's the only way I know of that works for me... When I didn't go at s downward angle water would drip back into the grow room.
Good luck

 

[Crusader Rabbit]

I only pull cold air into the 9*9 room and dont exhaust it. I exhaust the tents into the 9*9 room as well to regulate the temperature.

You water your plants and that water gets transpired into the warm air in your tents. That moist air is then vented into your cold 9 x 9 room so it cools down. Cold air can't hold as much moisture so the transpired water now condenses on your even colder ceiling.

You can take it from there ...

 

[mowood3479]

Id look to turn ur intake fan into an exhaust fan n make sure u also have holes for a passive intake. It won't cost you anything and should solve ur condensation problem.

 

[queequeg152]

exhaust the air in your garage or insulate the garage or dont dump humid air into the garage or heat the garage to above dew point of ceiling, or dehumidify the garage with a dehuy or AC.

only real solutions imo.

if you dump the air into the attic, you will have the same issue with your roof deck... unless your roof deck is agressivly insulated. but i doubt that considering your garage ceiling is cold in the first place.

i think for bathrooms you want something like 8 air changes per hour in capacity. this is to keep condensation from hanging out off painted surfaces for too long.

i think you should get a blower in the same ball park for this task. duct it out of the roof or wall.

 

[theLumberjack]

thanks guys. yea its bare plywood for the garage and it is pretty large... 30*30 or so. I thought I needed to try and keep some as much of the hot air in as possible so my tents didnt get too cold but maybe this just is not an option and it would be better to add a heat source inside the 9*9 on a cold temp on setting.

I will keep running the deuy for now and exhaust the 9*9 outside direct.

thanks all.

by the way. these 315's put off minimal heat.

when its 11 outside and 25 inside the garage I need 2 of them on to keep temps in that room 60.

 

[mowood3479]

I have an insulated room inside a cold barn. It gets -20 sometimes in winter here.. It's better to go out a sidewall instead of the roof.. Anyway I'd suggest using the dehu inside the insulated room.. Try that first they generate a lot of heat.. Mine actually raises the temp better than my space heater.

 

[LifeLess]

i had a set up about the same. 2 4x4 tents in a room i built in my garage. The room was half ass insulated. How and where are you venting the room to? You have to vent that air outside the garage or you will get so much moisture in the garage itself that youll get black mold very fast. Lesson learn the hard way. I vent my lights and room separately. My room vent is a low cfm fan sucking air threw a carbon scrubber then outside threw a roof vent. I keep all my light heat in the room when it gets cold. I run each tent on a diffrent 12 hour light cycle so theres always a light heating the room. The low cfm fan to the outside will keep the moisture level down. I also added a small electric room heater. I went with one that had a temp selector not just high or low. That also brings down the humidity. Good luck

 

[theLumberjack]

i wasnt venting outside... I thought the colorado dry air would be ok and that the garage wasnt air tight enough..... i am now venting with a 4 inch fan out a window... hopefully that does the trick. it only pulls from that room when it gets above 68....

i also am about to run these 12 and 12 to offset heat... I put the dehuy inside the room...
but there are also 2 35 gal res in there..

outside the room I added several buckets of salt... we will see if that helps too...

wife just yelled at me because the xmas decoration boxes were damp

 

[LifeLess]

How are things working out?

 

[mowood3479]

Ya if I get anything wet from grow condensation the old lady will have an anuresym

 

[theLumberjack]

honestly. so far a bit disappointed. i havent checked yet this morning.
yesterday it was 63% before work. warm day here. cold night. I turned dehuy off for the day. when i got home last night it was 78%

so I turned down the temp in my matrix room outside the tents to 60. Turned dehu back on But my 4 inch fan isnt keeping up. I plan to replace it with a 6 inch tonight for my exhaust. Although i have a 6" can sline inline, 6" can max, or a 6" ho to choose from all with different cfm.. any would clear the tents... and the 4 would probably provide adequate in...

 

[theLumberjack]

well at least these ladies are happy even if my wife isnt....

it was 45 in the garage 70% r/h

the dehuy is decnet size but didnt keep up even just over night. i had it set to 55 in matrix was 60%. temp was supposed to be 65 and it was 75.

but the rooms are both 85 degree surface temp and 75 degree room temp. 55% humididty.

as soon as i opened tents r/h in matrix became 80.

also, noticed my manifold system i was trying isnt working as well as i would like. either need a bigger pump or to add valves to all 6 off shoots.

 

[Buddyy]

Dialling in a room to correct temps and RH year round, which is in an area with large temp/RH variances and with walls that aren't insulated, can be quite a tricky task....but it's things like this that turn some of us from hacks to half decent growers/carpenters/handymen

I used to have water dripping from the ceiling until I got a duey.

I would like to give some advice but I can only repeat what has been mentioned above. Exhaust tent directly to outside. Have only passive intake for 9x9 room and for 30x30 garage.
good luck

 

[Mr Heechops]

you might wanna look at a HRV - heat recovery ventilator. Its an exhaust fan that can keep most of the heat loss that would occur with other fans. Its often used in airtight homes. Uses alot less elec. than dehuey too. It aint no silver bullet, it has its own issues too like icing over.

One way to approximate using a HRV is to use a regular exhaust fan with a long metal exhaust pipe that runs for a long way inside your building before exiting. The long run will act a bit like a radiator and thus save some of the heat.

 

[theLumberjack]

Thanks guys. Upgrading fan and exhausting directly outside has held me at no higher than 52%. I also have the debut in the 9*9 set to 55.

The salt buckets have collected me zero water.

 

[rives]

I don't think that it's been mentioned, but you can wind up with mold if you don't get this whipped. That's worse than damp Christmas decorations.....