Sealing room with 6mil plastic

[testing]

Building a new space and everything is framed. Planning on going fully sealed CGE and was going to seal the room by using 6mil plastic sheeting and Bituthene to seal the holes made by nails and staples. After the plastic is covering the insulation and framing we're gonna sheetrock it, mud and tape, caulk all seams, and then paint. So 6mil plastic lined room, all holes covered by Bituthene (which is basically roofing tar tape). Then sheetrock, mud tape caulk and paint.

So does this sound air tight? We're gonna do the same to the floor and ceiling. Does 6mil plastic hold air/smell adequately? Any suggestions/experiences would be appreciated.

Ps I wanted to do spray foam but budget does not allow.

 

[Weed Gretzky]

I grow in a "Sealed room". Before i built i thought i had to go overboard and seal up evey single staple hole and pin hole. I did my best but had some holes. My 50 lb c02 tank lasted 8 weeks so i realized now the plastic sheet was more than enough. Then again completely up to you how "pro" you want your set up to be.

 

[DemonTrich]

I did 2x 6ml, plus 1 layer of reflextix from HD. 50lbs in 8 weeks, holy shit bro. You running 500ppm or something? Lol

 

[dank.frank]

I don't ever put that barrier on the interior walls. Thick sheeting like that goes on the outside around the entire enclosure. You let insulation do it's job. With any significant difference between internal and external temps you can build up condensation/moisture and you don't want your interior walls getting any mold.

Skip regular drywall and use greenboard - like you would put behind a shower. Build your room from the inside out. Use caulking to line the back side of the walls before installing insulation, wrapping entire structure with plastic sheeting, and tacking up the exterior plywood.

The only exception I'd make to double plastic would be if planning to use an IR blocking material, which I'd still place on the exterior wall, prior to wrapping the structure with the 6mil.

Just my opinion and how I was taught.



dank.Frank

 

[sheik_yerbouti]

Don't want to hijack this thread but i thought it might be a good spot to ask this question since i just sealed my room so I can run CO2.

How long will your burner go before reflaming in a room without plants once its gotten up to 1500ppm? Its been a solid half hour and the ppm levels havent lowered barely at all. Anyone else tried doing this to test in there room? Will it be hours or days? Kinda assumed it would drop a little more rapidly. I know there is a few spots not totally sealed up as I'm not 100% complete.

 

[dank.frank]

Honestly, I've found 1500ppm to be unnecessary. On at 900 and off at 1100. Any benefit above that is so marginal vs the cost of running the equipment.



dank.Frank

 

[jahshaka]

I don't ever put that barrier on the interior walls. Thick sheeting like that goes on the outside around the entire enclosure. You let insulation do it's job. With any significant difference between internal and external temps you can build up condensation/moisture and you don't want your interior walls getting any mold.

Skip regular drywall and use greenboard - like you would put behind a shower. Build your room from the inside out. Use caulking to line the back side of the walls before installing insulation, wrapping entire structure with plastic sheeting, and tacking up the exterior plywood.

The only exception I'd make to double plastic would be if planning to use an IR blocking material, which I'd still place on the exterior wall, prior to wrapping the structure with the 6mil.

Just my opinion and how I was taught.



dank.Frank

Would love to see what you mean Frank as its a little hard to picture with all the layers of different materials etc. Any pics

 

[dank.frank]

Build you base - get the structure off the ground to control any possible root zone temp variations that come from placing plants on concrete - but - if on carpet then you want to get the structure up because of water and moisture. So, get the structure off the ground - you build a base/foundation on which to place the framing.

Once you have your framing in place, don't put on the exterior plywood first and build from the outside inward. You attached your interior walls (greenboard) in place first. This allows you to caulk all corners and edges to ensure a air tight seal.

Then you run all your pluming and wiring while you still have easy and clear access to the studs you might need to drill through.

Then you put your insulation in place.

Wrap the entire structure with an IR blocking material if you choose to do so.

Do the same with black 6mil poly.

Last, you finish with putting the exterior plywood in place.

Then, you can go back to the interior and hang reflective materials such as Orca or Reflectix, etc. You should have all outlet boxes and such wired and ready to install receptacles, plumbing tie ins, etc.

It's essentially backwards from how you would build a normal structure from the outside inward. Sorry. No pictures.



dank.Frank

 

[jahshaka]

excellent explanation clear as day for a numpty like me. Thanks again your info is priceless.

when you wrap the 6mil poly on outside do you staple and tape it or use some glue type tar shit?

 

[Chunkypigs]

you need to think about where the moisture in your grow room is going to condense if you don't line it with plastic inside.
most won't want that to happen inside the wall, black mold.

https://buildingscience.com/documents/digests/bsd-106-understanding-vapor-barriers

 

[dank.frank]

I'll explain with information from your link:

"Vapor barriers are also a cold climate artifact that have diffused into other climates more from ignorance than need. ... Incorrect use of vapor barriers is leading to an increase in moisture related problems. Vapor barriers were originally intended to prevent assemblies from getting wet. However, they often prevent assemblies from drying. Vapor barriers installed on the interior of assemblies prevent assemblies from drying inward. This can be a problem in any air-conditioned enclosure. ... In general water vapor moves from the warm side of building assemblies to the cold side of building assemblies."

I have never lined with plastic between the greenboard and framing. I've never had any mold on interior walls or in the insulation.

Keeping in mind, I'm discuss this from the perspective of building a "room inside a room" as a freestanding structure. I'm not discussing this from the perspective of building a home or warehouse where walls are exposed directly to outside environmental conditions and temperatures.



dank.Frank