Hi,

I have a room 120cm wide 80cm deep and 220cm high. I have no extraction unit at present although that will be changing in the not too distant future. While I don't have an extractor at the moment I need some advice about venting the room.

How many intake holes does anyone think I need? I intend to use piping with bends to stop any light leak.
Do I have the same amount of extraction holes?

Thanks in advance

wot lamp buffon?

400w lamp at present Mono.

My closet is 90cmx90cm, so similar, and about 8 ft high.......

I'm lucky that the closet is my loft access, so there's a hatch in the top......

When I used a 400w lamp I used no extraction or intakes at all, just left the door chinked open a bit, and left the hatch off the closet ceiling......this passive in and out did me fine, even though many round here....(Highlander and the likes) would be demanding 680cubmets/hour exchange rates..........

When I went up to a 600w lamp the temps did get out of hand, so I invested in a 20 quid bathroom extractor from Homebase, or band Q, somewhere like that......

As long as the door isn't sealed shut, there's a half cm all round the frame for intake, this is fine for me........I also got a clip on fan in there pointing at the bulb and the tops of the plants, just to minimise the risk of scorching.....got pretty hot in there in the sumer, but fine really......

If you're looking to lay some foundations here, thinking of maybe expanding/upgrading in the future, I'm sure you'll do better to get an Lti now.....just to say though, it's not always necessary.....I manage fine.....


Mono....x

Cheers Mono

My unit is sealed or pretty much and it's location does not allow for leaving the door ajar. I assume from what you are saying that I will only need a few holes for intake then.

i'd haver the intake as big as the output.
I had some problems with heat extraction in the past and was given some good advice from mono and highlander in particular...
you can find it on this thread
http://www.uk420.com/boards/index.php?act=...1b0bb08e6185677
best of luck

Cheers ha5mth and mono. I have what I need now.

hi Buffon,

my closet is 180cm wide x 60cm deep x 240cm high, also sealed with no door ajar option (and I'll be sticking a 600w lamp in there - MH bulb for rooting/early veg, HPS for flowering). Extraction is looking relatively easy - loft mounted 6" Lti shifting 420m3/h, but I'm also puzzling over how to get air in. Its got to come from the room the closet's in.

The best idea I've had so far is to stick a false floor in the bottom - one half at the front solid MDF, the back half open lattice MDF. The floor will be supported on 4" x 2" timber in a baffle formation (to prevent light leak) and I'm going to put air vents either side of the access doors.

What was your solution? Are you still using piping? If so, how are you going to disguise the presence of a number of holes in the wall (assuming you're going for a discrete appearance)?

hi Labrat,

The Extraction holes are on the roof of the cabinet and are not visible.

Had to think long and hard about the intake holes. The cabinet is in a garage, there is also a car in there it's a real tight fit. Along the side of the cabinet where the bumper of the car touches the cabinet I have the intake holes, it's not perfect but the car does not move so the holes can't be seen by anyone. On the inside of the cabinet I have put piping into the holes and given them a u bend to stop any light leak seems to be ok.

It's all passive so I hope it's gonna be ok.

I think I'll see how this grow goes before I go for an lti fan. Well unless it gets too hot then I will have to go for it.

buffon