Exhaust fan for dust control

[wxwise]

I have a basement shop, with numerous nooks and crannies that makes it impossible to caulk all of the places that saw dust could leave the shop and migrate through the rest of the house. I do have a dust collection system that I use religiously, along with a shop vac to collect dust from hand held routers and sanders.

Would a bathroom fan with large CFM provide enough "negative pressure" to keep the sawdust in the shop?

Thanks,
Scott near the Gateway City

[Steve N]

LOML says jokingly that most of the fun of a basement shop is being able to share the dust with all of the homes inhabitants, no matter how many floors above the shop they reside. Next Sunday marks our 35th anniversary, we have had a basement in our home in each home we have owned, and lived in. It was only in the first one I had a basement shop. 3 DC's and a number of point of use shop vacs, and there was still dust through that entire house. I had a downdraft table for sanding, before I knew they had a name. I can't think of a possible way you could mount even the most powerful bathroom fan, and it make any difference, but I sincerely wish you the best of luck.

Sign me, Mr unattached shop for 32 years

[fredhargis]

I agree with George, best of luck. You might consider an ambient air filter to capture it, but the bath fan isn't going to do much (methinks).

[Dave Diaman]

I have a large basement shop (about 1200SF). I installed two solid core doors for dust and sound. I have one at the top and one at the bottom of the stairs. I also have sound proofing insulation and double 5/8' drywall on the ceilings. The whole shop is basically soundproof. When I am doing anything like finishing or something that creates a lot of dust like resawing I have two 2200 CFM fans that exaust outside. I do need to open a window but even with that it is difficult to open the door due to the negetive pressure in the shop. I also have my shop on its own heat and ac so no dust or sound travels through the duct work. The only way dust gets in the house is on my shoes and I have a clean room mat at my door to help with that.

[jteneyck]

My setup is similar but not as extensive as Dave's. The key feature is a separate door to my basement shop which represents about half the basement. I put up a wall to partition it off and that's where the door is. I have a DC but it doesn't get everything and nothing if I'm freehand routing. There's really no way for dust to get into the rest of the house except on my shoes and clothes. I didn't add any extra sealing except for the wall/door, didn't see where it would be needed. I have a homebuilt HEPA filter to help get the fine stuff but it's useless if I generate a lot of dust from routing, etc. until after the worst of it settles.

John

[mikefm101]

jteneyck said:

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The key feature is a separate door to my basement shop which represents about half the basement. I put up a wall to partition it off and that's where the door is. I have a DC but it doesn't get everything and nothing if I'm freehand routing. There's really no way for dust to get into the rest of the house except on my shoes and clothes.

John

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+1 to this.

I put walls and doors in my basement shop and it seals in the dust. Our furnace is steps away from the shop doors and I always ask the furnace tech at cleaning time if he sees sawdust build up and there never is any.

A dust collector and air filter help. Also am religious to use a shop vac when sanding and routing. I sweep most every time I finish for the night. I wear a shop apron that stays in the shop. There isn't any ventilation to the outside to speak of.

Dust gets on my shoes, but I usually take them off at the top of the basement steps.

Dust in other parts of the house just has not been a problem. The walls and doors keep dust where it is made.

Mike

[jteneyck]

I forgot to mention that I have a hydronic heating system, so I have no concerns about sawdust getting drawn into an air plenum and getting blown up into the house. If I had a forced air system I would have put up the partition walls to separate it from the shop.

John

[TDKPE]

You'd be better off with a squirrel cage centrifugal blower rather than a propeller type axial fan. They're better at creating high pressures, or vacuum in this case, and they can't be overloaded even with a 'perfect' seal and no air flowing. I have an old window fan I use in a casement window when making a lot of dust or fumes, but I open another window for intake air. Seems to work for me. But if you want to pull a stiff vacuum, I'd suggest looking for an old A/C air handler or furnace that's being scrapped; the blowers are usually still good in them.

[Doug_H]

Scott,

The negative pressure idea is very good in theory, but it may be impractical to get the static pressure that you would need. I honestly don't know what static pressure you can get with a bathroom fan, but I tend to doubt that it would be enough.

If you have the space, an air cleaner might be something to consider. I had one similar to this Jet that worked well. web page
They are no substitute for dust collection at the source (shop vac, duct collector, etc) but they may collect the finer particles that escape point-source collectors.

Also, you should heed the earlier posts about dust on your shoes and clothing.

Finally, I have mostly given up sanding in favor of card scrapers. The dust from a ROS is virtually impossible to control/collect even with a shop vac attached.

All best wishes

Doug

[paulmaine]

I had a gable end vent with a built in fan at one of my previous home shops to use in the summer. It seemed like a good idea to shoot dust outside in the warm weather. The flat fins of the gable vent open when the fan was on.
A problem developed in that the fan which shot dusty air outside interfered with the oil furnace draft..the fire alert kept going off.