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Before I pour the shop floor, I would like to install a dust collection system. Are there any suggestions as to what material? Special concerns or ideas to make life easy later?
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Prescriptive codes don't address the connection at less common angles, so base the connection off more typical ones using bolts, structural screws, blocking, and steel tension ties.
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It will get clogged sometime in the future.
If it in under your finished floor, it will get water in it from time to time.
Solve those problems to your satisfaction.
*Treat it exactly like you would any drain system. Complete with cleanouts and plan ahead to minimize angles.Bury it at least 2" below the slab and use standard pvc piping.Where ever it comes through the slab, use a foam collar to isolate the pipe from the concrete.Should work out fine.
*I did a dust collection system in my concrete floor. It's been two years and I haven't had a problem yet. That's not to say that I did everything right and won't someday discover a problem. Here are some tips, though. I used galvanized duct. I joined each section with pop rivets to keep them from coming apart during the pour. I installed them on the top half of the duct only, at about the 10 o'clock and 2 o'clock positions so there would be nothing on the bottom half of the duct to catch and hold an obstruction. I felt pop rivets would be less likely to catch chips than longer, pointier sheet metal screws. I sealed all the joints with silicone caulk followed by wide plastic tape. The duct was completely surrounded by concrete, I did not bury it in the stone. Because of the amount of stone under the slab, and that the bottom of the slab is a few inches above the grade all around the shop, there will never be standing water under the slab up to the level of the duct. I had only a straight shot under the floor, with no elbows.Of course, think carefully about location because your choice would be "cast in stone" so to speak! Plug the ends to keep the concrete out during the pour.If you are going to have a stub up in the middle of the room, say, for a table saw with access on all sides, don't forget to bury an electrical conduit, too. The stub coming out of the floor should be metal, not PVC. For my table saw I securely fastened a coarse (about 1/2") wire mesh over the intake, so none of those long flexible strips of wood could make it into the duct and get caught.
*I buried 4" ABS plastic DWV pipe under my slab. This stuff is strong, waterproof, and not too expensive. I wouldn'y use PVC drain pipe, which seems too flimsy to me to be used in such a "permanent" placement. It's sealed with normal ABS cement, so it's waterproof.I also ran 1" PVC conduit to the same locations, for power.
*If you bury it...it makes no difference if you use abs or pvc or a garden hose, it will be protected. As long as it's waterproof and inexpensive. Galvanized ductwork(or any pipe) cast into the slab is foolhardy at best. Exposing the slab to cracking and the pipe to failure. It may have worked once, which is questionable, but not worth the risk.
*> If you bury it...it makes no difference if you use abs or pvc or a garden hose, it will be protected. As long as it's waterproof and inexpensiveTrue, but I wanted something that would endure getting knocked a bit from the flatwork sub while the pour was going on. ABS seemed better than the thinner drain pipe. I guess it depends on how much you trust the guys doing the work to be careful. I knew they had to deal with DWV pipe coming up through the slab in the past.
*BarryO,True has no buts.You used ABS and that's great. The fact remains, any will do. A buck's a buck.
*In response to LFred, I did not give clear details of what I suggested. LFred is correct, putting any large duct within a standard slab will cause a crack. In more detail, what I did was bury the duct below the slab, but surround it in concrete. In other words, I dug a trench about 10" deep into the stone base below the slab. The duct was laid 2 to 3 inches off this base. So it had a few inches of concrete underneath, then 6" for duct, then another inch of concrete above before having an additional 4" for the slab. It was all done in a single pour.Because the floor has radiant floor heat, the slab has 6 x 6 wire mesh throughout. The contractor did an outstanding job of preparing the base and placing the concrete. There is no movement of the perimeter walls, no movement up or down of the slab, and nothing more than one or two hairline shrinkage cracks.I wouldn't say that I'd recommend what I did over the other methods suggested. I did, however, want to avoid static buildup that might come from plastic pipe, and therefore worked up a secure method of working with galvanized despite the extra concrete.
*Pouring a large pipe into any slab, even inside a thickened footing is not a recommended procedure. It is always better to keep a consistent slab thickness and isolate pipes and such from the actual slab. It's not worth the risk.
*so what your saying is, the pipes go below the 4" slab? What exactly is the issue with static?
*David, Is it to late in the game to froego the concrete all together? a wood floor will be much more comfortable if you will be spending alot of time on it.With a crawl space and joist system you can insulate and be able to run wires and ducts or whatever underneath.Just a thought.Enjoy your new shop!Mr T
*Some people say that there is a slight chance of a static electricity buildup with plastic duct, which could conceivably spark and cause the dust in the duct to explode. But, many commercially available dust collection systems are made with plastic duct.Unfortunately, I've never seen any expert write on the subject and support his opinion with data, either from laboratory tests or accident data, so I can't say who's right.
*Thanks to all. I think your right about the dust-static issue. I know there are guys here who are very knowledgable. Thanks in advance.
*The Knots forum has had some good discussionas about DC sizing and static risks (or non risks according to some).