Humidity/ temperature

[lattitudepirate1]

Im running in a 4x4 in my uninsulated loft and so far, everything seems to be pretty stable. Lights on I get a steady temp of 24/25 and my humidity sits happily in the high 50s/ low 60s during lights on. The plants albeit small are racing along at day 8.

Coming from outdoors only, i'm amazed at the speed of growth that 18/6 has given. wow!

 

During lights off my AC infinity 6inch fan is working at speed 2/3 (out of 10) to maintain a RH of 65%. I am using a seed heat mat for heat during lights off only.

 

My issue is when I water, I get a big spike which lasts +12 hours before falling into the above parameters. Ive only ever grown outdoors and this is proving to be a steep learning curve so far! 

 

 

Ive tried to do as much reading as possible and ive come to several conclusions which id love some input on from your good selfs over here!

 

Do I add a tube heater? Use a timer at the wall to come on 15 mins before lights go off in the hope it holds my temps higher and preventing a drop to 20ish and spiking humidity into the 70s? If I can hold the temperature closer to 25 throughout lights on/off - would this solve my issues?

 

Add a dehumidifier? I understand that I would require a dessicant dehumidifier as loft temps are low for compressor types? Could I run this in the tent? Maybe lose the heat mat as the the dehumidifier will provide heat?

FYI... My loft space has a large footprint and the property is old with a half inch gap around the soffits of the property. I assume this would mean stabilising 'lung room' humidity is out the question based on this.

 

 

 

I also use an AC infinity cloudray fan for circulation. This also seems to bring my temps down and humidity up. 

 

 

Any and all advice would be much appreciated. Thanks all

 

 

 

 

[Goodbloke]

Going to leave detailed advice to others, as I've never used a loft. 

I ran a 1x1 in an unheated small bedroom (attached to the heated main living area), pulled input air from the main heated area and extracted outside. It needed a dehumidifier & an oil filled rad. 

Don't know what size tube heaters go up to but I'd be surprised if uninsulated loft grows don't require far more heat than that. 

Humidity will get far worse, your plants are tiny at present, a full flower 4x4 is going to get through a considerable amount of water daily. You're going to be moving lot of air through the tent, taking heat with it. 

I've got a small 0.75x0.45 area enclosed within a bedroom, the space has 2 x 2' tube heaters, think they're 120w each and a dehumidifier running in the room.

Proper more useful info on the way I'm sure, but I'd start reading about loft grow insulation projects and light sources to compliment LED's that also add more heat. 

[lattitudepirate1]

8 minutes ago, Goodbloke said:

Going to leave detailed advice to others, as I've never used a loft. 

I ran a 1x1 in an unheated small bedroom (attached to the heated main living area), pulled input air from the main heated area and extracted outside. It needed a dehumidifier & an oil filled rad. 

Don't know what size tube heaters go up to but I'd be surprised if uninsulated loft grows don't require far more heat than that. 

Humidity will get far worse, your plants are tiny at present, a full flower 4x4 is going to get through a considerable amount of water daily. You're going to be moving lot of air through the tent, taking heat with it. 

I've got a small 0.75x0.45 area enclosed within a bedroom, the space has 2 x 2' tube heaters, think they're 120w each and a dehumidifier running in the room.

Proper more useful info on the way I'm sure, but I'd start reading about loft grow insulation projects and light sources to compliment LED's that also add more heat. 

 

Thanks for the info. This gives me more food for thought! 

 

Warm air in seems to be the way to go. This weekend I think ill have a look at cutting a hole in the corner of my airing cupboard, making good with a louvre vent and attempt to attach my intake to that.

 

I had assumed that my LEDs and heat mat would provide me enough heat. Ive got some thermal blankets and stuff on/ around the tent to help with temps but guessing ill need some more. 

 

Its the taking of heat with extraction that seems to be the issue which lead me to think that running dehumidification inside the tent would be best, but others suggest it leads to more problems.

 

Im pretty handy with DIY and happy to throw in some additional heating or a dehumidifier... Just looking for a foolproof suggestion that this fool can put into practice. 

 

Thanks for the reply!

[Woozy]

I was growing in an uninsulated boarded loft, only at certain times of the year could I get everything bang on, in relation to temp/ humidity. I ended up building a room out of kingspan insulation in the loft and did away with the tent. I pull air in from the house too, as that helps to steady the temps especially in winter. I run a compressor dehumidifier in my room and use an oil filled rad to top up the heat as well as heat mats under the plants to keep the roots warm.  lots of insulation is key to making a stable environment

[sweettooth]

@Woozy in a similar boat mate. been growing in an uninsulated boarded loft for the past 4 years, sunmers too hot, winters too cold and expensive and causes endless condensation inside the tent. lots of duvets

tents piss me off, going to kingspan the entire thing and build a room, will be much more economical. 

 

@lattitudepirate1 to answer your question, humidity will spike as you're adding humidity via watering. youve hit the nail on the head about pulling in warm air from your airing cupboard,  wish I had one. Annoying thing about cold lofts is constantly pulling in colder air and having to constantly heat, same woukd happen with a lung room or lung tent,  you're just pissing those King Charles notes up the wall in leccy costs. Last few winters I sealed up and ran co2 and had a small dehumidifier running inside, temps would still rise to a horrible level. I'm going back to Hids & leds over winter, mixture of cmh and led, maybe a hps as well 

 

Dehumidifier wise now, I still run one but have rigged the output via ducting into the tent so at least the air going in is clean and dry, defo helps lower the humidity. It's got a Merv filter so will remove any bugs, pathogens, spores etc,

 

Good luck with your venture