TimTucker,
I thought I would share some thoughts from my experiences even though I may be dancing around your question or going beyond its scope.
Since I began woodworking as a hobby, I have had woodworking shops in 2 basements and 2 attached garages. I moved 3 times. I am now woodworking in an attached garage. I always thought I wanted a separate dedicated building close to the house – I can only dream.
While I was never 100% successful in preventing dust from entering the home, I was mostly successful. At least the wife never really complained. I achieved what I considered satisfactory results be paying close attention to isolating the workshop air from that of the rest of the house. I believe this is important no matter how good a dust collector you may have. By the way, in the first shop (basement), I started with no dust collection. Then I upgraded to a ½ hp bag system that performed poorly. Only in the last few months did I upgrade to the CV 1800.
I prefer commandeering the garage over the basement solution. It is much better for a number of reasons. There is far less worry over dust and noise entering the home from the garage. There is no HVAC duct work in typical garages. Make a good seal into the attic, if access is in the garage, and around the door that provides access from the garage into the home and the house is pretty well isolated. Good weathering striping installed in a workmanlike manner does the trick. Also sealing any receptacles in the garage in wall(s) common the house would be a good idea. If this sealing is done, the only dust making its way into the house is tracked in on your feet and clothes. You could probably woodwork with no dust collection at all in an attached garage without worry of contaminating the house with dust – except tracking in dust.
In addition to the ease of isolating the attached garage from the house, you can receive delivery of machinery and lumber easily and get fresh air when the weather is nice by simply opening the garage door. Walls separating the garage from house are normally insulated, providing some measure of sound abatement. However, all is not good in the attached garage. First, the cars either set outside or you have to constantly move cars and machines. Second, the garage is typically unconditioned space. Depending on where you live, you may want to heat or cool the garage. In so doing the garage door, attic and exterior walls should be insulated.
In my view setting up the shop in the basement is more problematic. Considerations when setting up a shop in the basement include: sound isolation, mechanical systems isolation, lighting, flooding, laundry room location (typically in the basement), moving machinery, moving materials, ceiling height, and access to the basement from the house.
Material and machinery access is made a whole lot easier and flood less of a concern if the basement is a walkout at grade. Moving large finished projects, scrap, and collected wood dust out of the basement is also much easier with a walkout basement. If not a walkout, a basement door where you can immediately exit to the garage or to the outside is important when it is time to empty the dust collector. The wife will kill you if you pack your full dust collection drum through her kitchen or living room. Also the number of turns and the space available to make turns is a consideration, as is the construction of the stairs themselves. After all you have to get heavy machines into and at some point you or someone else will have to remove them from the basement. Tight turns or stairs that collapse under the weight of two men and a heavy machine can impede setting up the shop.
Forced air ducted HVAC systems can be quite effective at moving dust throughout the house. If the home has a flame fired (propane, natural gas, fuel oil, etc.) furnace and/or hot water heater, keeping the burners clean is a major concern and isolation from dust must be very effective. High efficiency mechanicals that draw combustion air from outdoors help, but I believe isolation of the hot water heater and furnace from dust is still important, since these are not systems suited for a dusty environment. When it comes to sound isolation, insulation is a must in the ceiling joist bays, assuming you want to keep peace with the family. Even with this done, sound is transmitted through the drywall or drop ceilings into the first floor living space. Ceiling height of 8’ or more is workable. Less than this make is far more difficult to shoe horn a tall dust collector in place. Flooding of a basement workshop would be a nightmare.
If you opt for the basement, I would recommend an unfinished basement. I am sure you did not want to hear that. Finishing a basement is a major expense; made less if you do the work yourself. But then there is no woodworking for a year or so if you finish the basement yourself, unless you are faster than me. The reason for the unfinished basement recommendation is that you can plan effective mechanical systems and sound isolation. You can plan and build a mechanical room that is well isolated from the woodworking environment. There are sound absorbing products like denim or mineral wool or spray foam insulation and sound absorbing drywall that you could install.
As far as increasing the dust collection capability of your dust collector, more may be better. However, it is probably next to impossible to remove all dust from your workshop. Collecting 100% of the dust from sanding and saw operations is, in my experience, next to impossible. Then there are handheld machines like the router and circular saw that are dusty machines. Certainly you can collect more dust with a bigger dust collector, just not all of it.
Back to my dream; a standalone building has obvious advantages. However, there are disadvantages. It has to have power, and a lot of it (100 amps). It probably needs to be heated or cooled, which means insulation and mechanicals. Access to the house is a consideration; I would hate to walk 150 feet through 2 feet of snow to woodwork. Also communications may be important. An intercom to the house and a telephone is a consideration, if, like me, you are not on the cell phone grid – or solve both of these problems by getting on the grid.
Finally, I looked at a lot of houses during my three moves. I did not find the perfect answer, but I am sure there are few gems out there. I hope I helped a little. Anyway, Good luck!
