Venting thru the attic

[solarz]

Hi ICMag,
i have a question about venting thru the attic in my grow closet. I've tried to get up in the attic, but i can't physically get above the attic where i want to cut the hole to place my exhaust fan. My question is if there is an efficient way to make a "good cut" without actually being able to be over the place where the cut is to be made. To sum it up, i'll be making the cut from inside the closet, with no access to the attic space above it.

I'm not experienced in making a cut like this, so i just wanted to ask if there was anything i need to be careful of in particular when cutting from inside the room with no attic access. Thanks in advance.

solarz

 

[1G12]

Yeah, it always pays to be careful. You could run into electrical wiring, sprinkler system water lines or cable TV lines.

 

[tree top flyer]

Hey Solarz, I'm not that much of an experienced grower but I have done a fair share of cutting into walls... 1G12 is right tho, not being able to get up there greatly increases the risks of hitting electrical wiring, or taking out a portion of framing that you really might regret. My suggestion would be to stick with the less intense tools such as a hammer and chisel and take your time. Go through layer by layer, sheetrock first, then score any boards an pry them off. I pays to be careful so you might as well shut the breaker off to that section of the house just in case. It's hard to say much more without seeing the closet and knowing the general architecture of your place. Good luck and I'll check back to see how things are going.

 

[solarz]

I've looked at it looks like i may be able to get over the closet in the attic, but it is an EXTREMELY TIGHT fit. i''d have to actually lay down and somehow slide across the planks thru the attic to get to that side of the house. The attic entrance is in the garage (front-right left side) and the bedroom closet is in the back of the house (back right). The reason it is so difficult in the attic is because all the ceilings in the house are of different levels and some actually go all the way up with skylights. So in the attic, some spaces are at a level where you can "squat walk" around...and other areas are like i described above, where you have to lay down to get to spots. Thanks for the advice/suggestions. I'll keep thinking about it...and if i can't figure anything out, i'll just have to figure out how to exhaust out of the "door" of the closet...which is a whole different issue (which is really why i want to vent up into the attic). lol. Thanks again

 

[Guest]

Hi solarz,

Venting in the attic is a great idea! You can even put a fan attached to a carbon filter in there to save space in the growroom as well as cut down on noise if you so choose. Its usually a tight fit where you need to cut your hole, especially if you are cutting the hole near where the attic roof starts to slope. You say that you can possible fit if you lay down, and I can tell you that you will fit! haha Its always a pain in the butt doing things in the attic, but the best tip I can give is to prepare your wardrobe!

Long sleeves, pants, socks, respirator if you have one, if not a wet t shirt tied around your face will work. If you have clothes with drawstrings to keep them shut use them, if not put your pant legs inside your socks or tape if you must. These are extreme measures, and not mandatory but they can make life a whole lot easier up there. You will need to lay flat on your stomach and ninja crawl along the wood cross sections to get into position. Careful not to slide off these support beams and fall thru your drywall. This way you are in position to work and can tackle the job face first and not take up too much vertical space by laying on your side. Being comfortable as possible is very useful, so taking those wardrobe precautions before entering that itchy attic may not seem so crazy now. You will feel invincible to the insulation and start to laugh in its face!

Try and move the insulation away from the area you want to work in, so you have a good line of sight and can trace cut your hole perfectly. All you really want to do is make sure there is space to cut the hole, and you wont hit elec wires or a piece of the frame like the others have said. Its best to cut the hole from above while you are in the attic, but if you must you can always cut from below once you have cleared the space from in the attic.

some tips

-do not do this if the outside ambient temp is high, wait for night or morning if you live in a hot climate.

-bring all tools needed, you don't want to get into position start to work and realize you forgot your hole saw.

-clean up any debris you created, leave no trace of being there. no pieces of tape, tools, pencil, nothing.

-after everything is set up properly, get back to the attic and look around. you will see your trail. you will see where you cleared space to work, and where you slid down and matted all the fiberglass with your ninja moves. take the insulation laying around you and cover up your snail trail.

-if you use insulated ducting, it will allow you to cut a more crude hole. you won't have to be on point with the measurements as much, as the insulated part of the ducting can contract and expand enough to fit the hole and keep it tight fit. Still, approximate and measure your hole. You don't want to cut it too large, this will create more work to fix. You want that ducting to fit nice and snug.

this isn't the only way to do it, as anything can be done a number of ways. modify anything to fit your needs and specific situation.

don't vent out the door, the attic is so much more stealth! if you HAVE to, this is a simple way to work from the closet side. you can always cut a smaller hole in the cealing to fit your hand in and see if there are any beams or wires nearby. this sometimes will work first try, but sometimes you will have to make a few holes until you "guess" right. Start with a small drill bit to see if you hit wood, if its clear then you can put a hangar or something into the hole and sweep it to see if it hits anything. put a hangar in, bend it 90 deg so it will sweep for you as if you were in the attic. gradually increase the size of the hole until you know whats above. This can work great, but can also be just as much as a pain to get right as going into the attic. I suggest this as a last resort, just before exhausting out the door.

oh I forgot the first and last steps! blaze, and crank some tunes

 

[laidbackgreen]

I have cut many a hole in attics and don't understand why you wanna cut the hole from inside the attic. Just do it in the closet.

Find your studs (cause that is where the wiring will be connected to) and cut the whole between them. There is numerous ways you can find studs, stud finder purchased at local hardware store, do the sound test (pound with fist or other tool to determine where stud is) or use a very small drill bit to find the studs by making small holes.

Remember when you find the stud the next one will be 16 inches apart. Just take a razor knife and go to town. Hell I don't see how it would be possible to hit a wire unless you are using a chainsaw to cut the holes. You will run into insulation first before any wires anyway.

Hope this helps, I have built many a home.

 

[solarz]

Thanks for the replies...i think i am going to attempt to crawl thru the attic to spot where i want to cut the hole because i have tried to find studs in this closet and i just can't seem to find them. I have one of those stud finders from hone depot...but i NEVER stands up telling me that there is a stud anywhere in the closet (and i know this just can't be true). From me not being able to find studs...i have to rig up a holder for my 600w HPS because i couldn't screw into the ceiling for lack of knowing where beams/studs are. Maybe i'm using the little stud finder wrong, but i've just been slowly waving it up and down the walls and i've found nothing. But either way...i'm going to attempt to get this hole cut in the next few days. I'll keep yall posted on the progress.

Also, im not using any power tools so it is going to be all manual labor...any suggestions of an efficient NON POWER tool that i could use. I have a pretty sharp razor knife, but i'm not sure if that would work. Should i get/use a hand saw or something similar? Thanks again.

 

[messn'n'gommin']

Just a thought, but, exhausting into the attic is not really a problem until one considers where the air is being drawn from. Drawing from the house and exhausting to the attic will increase your heating and cooling costs dramatically, but the logistics in your situation may not allow any other option than to do it that way.

That being said, a razor knife will do, but, it will take awhile. A drywall/keyhole/jab saw will do the job a lot quicker. Make your cut just insideyour mark and fine tune the cut with a coarse rasp (have a sample piece of the ducting you will use on hand to dry fit with). Laidbackgreen has valid points to consider, but having done rough framing before, I think you should know that some may not follow standard building practices like LBG does. Just a heads-up to make sure before you go jabbing metal into a wall you cannot be sure whether or not there is electrical wire or pvc water lines running in the same space.

Namaste, mess

 

[badugi]

Just a thought, but, exhausting into the attic is not really a problem until one considers where the air is being drawn from. Drawing from the house and exhausting to the attic will increase your heating and cooling costs dramatically, but the logistics in your situation may not allow any other option than to do it that way.

Not sure I get it. Why will the attic being warmer than usual be a problem?

 

[messn'n'gommin']

Not sure I get it. Why will the attic being warmer than usual be a problem?

Exhausting cooled or heated air to the outside makes the A/C or furnace cycle much too frequently trying to keep the inside air at thermostat settings. Trust me! It sucks big time paying double or even triple electric and/or fuel oil and/or natural gas costs!

While, exhausting inside the house will tend to ease heating costs in winter, the small extra cooling needed in summer makes it more of a push. The down side to exhausting into the house, is the ever present danger of mold from higher humidity levels. A definite must to watch out for!

Namaste, mess

 

[badugi]

Right now I'm pulling cold outside air from a window and running it through a closed circuit system of air-cooled hoods (and A/C unit) and exhausts into the attic. There is no central A/C or heating system.

How much will things suffer? I imagine humidity isn't much of an issue, since it's simply taking outside air, warming it up a little and sending it to the attic... right? (And only at night.)

 

[Joe Hawkins]

Your home wont lose heat if you are pulling air from one window in the same room, if you were venting the whole house, then maybe.

Im sure you missed what someone said earlier, because you seem to still be thinking of making that cut from the attic, but you dont make the cut from in the attic, you do that from your closet space, Honestly good luck gettng into the roof space you described then trying to actually do manual dexterous work in high heat with out falling through the ceiling.

just use your hand and common sense and find that hollow part between the studs, guess if you have to, CEILINGS CAN BE FIXED.
As mentioned by someone before on this thread, the electrical wiring will be running with your studs, so dont panic.

I just used a drill to cut out the hole, but wear some safety goggles or you'll get eyes full of plaster dust.

you will still have to get into the roof space to rig up a fan to PULL the air, doing this should be enough of a task in that small space

 

[messn'n'gommin']

Right now I'm pulling cold outside air from a window and running it through a closed circuit system of air-cooled hoods (and A/C unit) and exhausts into the attic. There is no central A/C or heating system.

How much will things suffer? I imagine humidity isn't much of an issue, since it's simply taking outside air, warming it up a little and sending it to the attic... right? (And only at night.)

Ahh...ok...I understand now. Solarz only mentioned cutting a hole into the ceiling of his closet for his exhaust. He made no mention of where his intake was originating from. So, as a qualifier, I said that it depended where the fresh air was being drawn from and made my suggestions from that standpoint. Hope this clears up any confusion I may have caused. Thanks for the headsup Badugi.

Namaste, mess

 

[badugi]

Sorry for the misunderstanding, I wasn't trying to point out anything... but rather asking a question as I'm really unfamiliar with how buildings and central systems and stuff works. I don't know much about how central systems are set up and how temperatures in different parts of the house may affect it.

In my scenario, do you think anything will suffer? I imagine I'll probably be the only house without frost on the roof in the winter (if it were ever to frost here, unlikely), but besides that?

 

[messn'n'gommin']

Sorry for the misunderstanding, I wasn't trying to point out anything... but rather asking a question as I'm really unfamiliar with how buildings and central systems and stuff works. I don't know much about how central systems are set up and how temperatures in different parts of the house may affect it.

In my scenario, do you think anything will suffer? I imagine I'll probably be the only house without frost on the roof in the winter (if it were ever to frost here, unlikely), but besides that?

I think you have a better grasp of it than you give yourself credit for, at least on an intuitive level. That being said, most heating and A/C systems are usually separate units that use the same blower and ducting to push the heated or cooled air to various parts of the house (or apartment). Somewhere in the house, usually at some low point, will be a large grill that covers the hole for the "return." This is the primary source where the blower gets the air from to "condition" and recirculates it throughout the living space, while both heating and A/C units are hooked up to a thermostat controlling the interior temps. As the air loses its temps through convection, the thermostat kicks on the blower and recharges the air to its designated temperature. Exhausting this conditioned air to the outside causes the thermostat to cycle the furnace or A/C units to get back to preset levels. The more conditioned air exhausted to the outside, the more the units cycle, to an almost constant level.

However, and here is where your intuition comes into play, drawing the air from and exhausting to the outside on a closed circuit, means you have bypassed the HVAC units without affecting inside air temps. As far as the way you describe your setup, it will affect the temps in the attic to a minor extent, but, you can add passive or active exhaust systems in the attic itself to help cool temps as well. But, usually isn't necessary

This explanation is a bit simplistic and full of errors, and can be picked apart by most anyone familiar with HVAC work, but is essentially the process. Hope this helps a bit.

Namaste, mess

 

[badugi]

Thanks so much for the detailed explanation. It helps a lot.

Despite some recent disagreements on some topics I'm really starting to like hoosierdaddy's and your level of expertise in a lot of technical fields. I also really like the well-written posts that explains and illustrates everything well with plenty of detail.

Hope you guys stick around for a while, you guys are valuable assets and can probably help answer some of my questions the future.

 

[messn'n'gommin']

I am more than humbled. But, I suspect that the student is fast becoming the teacher.
Peace, bro.

Namaste, mess

 

[smurfin'herb]

I have never personally vented into an attic, but i wouldnt reccomend it unless you wanna have no snow on your roof in winter when everyone else does! It can also get humid and condensate up there with the cold roof and warm attic, leading to mold. Have you ever been in an attic in the summer...? Hot as ballz!!! Imagine routing growroom heat to those existing temps! Pff talk bout an easy FLIR target! Anyway i always route through the attic AND then thru the roof. Its easy, if you wanna know how to do it the right way without any leaks, just pm me. Heres a pic from up in the attic of a place i did. The rigid duct goes thru the roof and connects to an umbrella cap. I sealed it using a 4" modded to 6" roof pipe flashing. I then sealed flashing with roofing cement and silicon. I sealed the inside with silicone just as a precautionary measure.

 

[badugi]

Is 6" enough to get 4.8k of exhaust out?

 

[smurfin'herb]

funny. i was runnin 4.8k out of that exact setup in the pic. Thats the exhaust for the lights for two diff rooms, hence the y-duct. Is 6inch enough you say..... well its all you got to work with cuz the lights only have 6inch cooling acceses. But if you were referring to exhausting your outtake for the room, i did 4.8k in a 15x12 room, and used 6inch fans for in/outtake and it worked fine, as it should if you do the math on the cfm ratings on a vortex 6in. for that size room. 6inch worked ok, 8inch would have been better tho.