I have a large metal outbuilding that the previous owners built a 15' x25' office in. 2x4 walls and 8' ceiling with insulation. Paneled walls, drywalled ceiling. In the middle of summer with a dehumidifier running it feels like a/c in there . Doesn't freeze in winter. It was too nice to use for a shop so I use it for storage. I built a shop that I smoke in, but not insulated as well. After 7 years of living here, the " office" is too nice for storage so I want to turn it into a cave/ shop. Just need a way to vent smoke. I saw in another post where they used high velocity bathroom fans. In the shop with the woodburner going I open a window with a fan in it blowing out. There is no window in the room I want to use. Anybody have any ideas?
Ventilation for cave
- Thread starter nightowl
- Start date
I use a bathroom fan vented out side in my heated shop. It works well however it has a tendency to also remove the heat as it removes the smoke. The fan is a cheep one, not a high velocity. I am considering a filter which will not exhaust the heat.
I just got this installed in my heated shop last night as a matter of fact. Still have to do some cleanup and get the power cord situated, but you get the general idea.
Me and a buddy smoked in there right after hanging it. It does a good job of getting rid of the smoke. Not a bit of smoke could be seen lingering. It doesn't get rid of all the smell though. I would say it did cut the smell down by about 50% while smoking. Leaving it on for a few hours after we finished I would say the smell was 75% gone. The nice thing though, is that it was putting all the heated air back into the room so I wasn't losing any heat. I think for a complete solution to the smell as well, you almost need to either vent in fresh air, or vent the air completely out.
My next project is to find something that will get rid of most of the smell when used in conjunction with the air cleaner.
Me and a buddy smoked in there right after hanging it. It does a good job of getting rid of the smoke. Not a bit of smoke could be seen lingering. It doesn't get rid of all the smell though. I would say it did cut the smell down by about 50% while smoking. Leaving it on for a few hours after we finished I would say the smell was 75% gone. The nice thing though, is that it was putting all the heated air back into the room so I wasn't losing any heat. I think for a complete solution to the smell as well, you almost need to either vent in fresh air, or vent the air completely out.
My next project is to find something that will get rid of most of the smell when used in conjunction with the air cleaner.
Jfire
BoM 9/9' 9/11' 8/12'
There are 2 options. Both will need a fresh air entry to prevent negative pressure in the space. Negative pressure is the last thing u want in your cave. Moisture issues etc.Calculate Cfms needed first. Get your volume of the space LxWxH wich will also be your cubic ft. First the bath fan. Cheap, lower cfm option. Generally 200 cfm or less. Even with smaller inlet openings you'll be fine with positive pressure. Multiple bath fans can be used but noise is always a issue. 2nd option. Inline eduction motors. Higher Cfms, more cost, less noise. They require a bigger fresh air intake opening to allow higher Cfms being pulled by the eduction motor as well. Also more labor and money involved in parts and installation. You'll need bigger ductwork for this which cost considerably more. If your not smoking with others often a bigger cfm bath fan 180-220cfm fan is probably the better option for you.
Jfire
3rd option: air cleaners are not recommended by me unless theyre added to options 1 or 2. They clog and cost more over time.
Jfire
3rd option: air cleaners are not recommended by me unless theyre added to options 1 or 2. They clog and cost more over time.
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Good info JFire. For my setup above, what would you suggest I do in addition to my air cleaner? My space is roughly 30 x 30 x 12. Or would you recommend I ditch the air cleaner and do something entirely different?
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I built my own ventilator. I used an HVAC air handler squirrel cage fan and mounted it into a frame of 2x4. Then covered the frame with 3/8 ply. I cut a rectangular hole in the side to fit an AC register grill. One end vents outside via to a 4" louvered dryer vent kit. I had the fan on-hand, the remaining parts cost less than $30.
forty
forty
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Pic of ventilator. ...https://docs.google.com/open?id=0B_R9hHHVCbZieFdjTmZxWkVoYlU
Jfire
BoM 9/9' 9/11' 8/12'
Forty,
Do you have a window in that room or another fresh air supply for it? If not you have a good possibility of creating a negative pressure in that room or the house in general if it's in the house. I would be concerend with moisture issues if you do not have a fesh air source for that set up. FWIW
Jfire
Do you have a window in that room or another fresh air supply for it? If not you have a good possibility of creating a negative pressure in that room or the house in general if it's in the house. I would be concerend with moisture issues if you do not have a fesh air source for that set up. FWIW
Jfire
- Joined
- Aug 18, 2012
- Messages
- 70
The cave is a 12x16 metal shop building. I installed electrical, insulation, sheetrock, and flooring after they set the building. The opposite end of the building has an AC unit mounted in the wall and cools the building well in Houston summers. Fresh cool air is blown in at a greater rate than I pull it out with the ventilator (stays cool even when the ventilator is on). The AC unit also acts as a passive vent even if it is not running when the lever is pushed to the exhaust position.
There was a little guess work on sizing for the AC register in the ventilator. Too big and it would suck out all the air, too small and it would not get enough flow. I started with a 12x6 with the intention of changing to a 12x12 if the need arose. As it stands the AC cycles on and off so I've left it alone.
The fan is from the blower of a 3 ton home AC system. Pretty big, but I don't know a specific CFM rating. I hardwired it for "medium" speed when I installed it. I'll try to take the panel off and shoot some pics of the blower motor later. It looks a lot like this.
The ventilator is also good at removing paint fumes, welding smoke, saw dust particles, etc. Keeps the shop free of smoke with up to 3 buddies stogies going.
There was a little guess work on sizing for the AC register in the ventilator. Too big and it would suck out all the air, too small and it would not get enough flow. I started with a 12x6 with the intention of changing to a 12x12 if the need arose. As it stands the AC cycles on and off so I've left it alone.
The fan is from the blower of a 3 ton home AC system. Pretty big, but I don't know a specific CFM rating. I hardwired it for "medium" speed when I installed it. I'll try to take the panel off and shoot some pics of the blower motor later. It looks a lot like this.
The ventilator is also good at removing paint fumes, welding smoke, saw dust particles, etc. Keeps the shop free of smoke with up to 3 buddies stogies going.
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Sorry to keep jacking this thread, but I could use some help on my cave build as well from those more in the know.
I am trying to decide between 2 options for my 25x25x12 heated garage. Any input is greatly appreciated.
Both options include 3 Panasonic 340 CFM Inline Extraction Fans.
Both options include 2 fresh air inlet vents located on the ceiling directly above the radiant heater that is hanging from the ceiling. I figured this way the cold intake air would funnel in over the radiant heater and perhaps get warmed up as it enters the room. If it doesn't get warmed up as it enters then its as good a spot as any I suppose.
Option 1: Have one exhaust vent per fan all lined up on the ceiling in the center of the room
Option 2: Split each fan into two exhaust vents and spread them around the room
I am trying to decide between 2 options for my 25x25x12 heated garage. Any input is greatly appreciated.
Both options include 3 Panasonic 340 CFM Inline Extraction Fans.
Both options include 2 fresh air inlet vents located on the ceiling directly above the radiant heater that is hanging from the ceiling. I figured this way the cold intake air would funnel in over the radiant heater and perhaps get warmed up as it enters the room. If it doesn't get warmed up as it enters then its as good a spot as any I suppose.
Option 1: Have one exhaust vent per fan all lined up on the ceiling in the center of the room
Option 2: Split each fan into two exhaust vents and spread them around the room
Haha thanks man. Got any electrician skills? I think the only hard part is going to be cutting holes in the roof for the 3 vents and wiring this all up to a switch. I'd also like to get electronic dampers on the fresh air vents so I can close them when not smoking
Jfire
BoM 9/9' 9/11' 8/12'
Cold air moving fast will not warm over radiant heat that Is far away. It's why you see retail stores using units with heat coils inside the blower motors/ units. U would be better off passing that air over a convected heat current. Think gas blower in your hvac. Or by placing a radiant coil temper in each opening of fresh air.