In an earlier life I owned, designed and built auto/truck service facilities. I've put in several different exhaust extraction systems over the years. First it was just cutting a port into the garage doors and connecting exhaust hoses (the type you describe). This didn't work. Exhaust gas would leak around the hose and some exhaust systems on the vehicles themselves leaked. Air pressure was positive in the hose which promoted leaks. Big headaches, literally!

Next I installed an inexpensive exhaust fan in the attic and ran round ductwork over and down to the back of vehicle areas. This worked great as the system sucked the exhaust out (negative pressure in the hose) and shot it out the roof, away from the mechanics (and customers, who tend to hang around the garage doors). The problems were: the fan sometimes failed because of the hot, moist gasses clogging it up; the ductwork was flimsy (and ugly) and would get pulled apart when a mechanic forgot to disconnect the hose; and each unused port had to be covered with a cap so it wouldn’t suck all the heat out of the building . If a shop rag got sucked in and got to the squirrel cage, major problems!

The third time was a charm. We closed the shop between X-mas and New Years and had at it. We cut 160’ of trench through the slab around the shop and installed heavy round cementatious duct made for underground exhaust systems. Steel exhaust hose ports with sliding metal covers were located at each workstation. I hung a purpose designed variable speed exhaust fan (with HEAVY DUTY squirrel cage) on vibration dampers from the ceiling and connected it to a large underground plenum with a clean-out hatch at the end of the trench. Worked great! The exhaust hoses would go down into the ports in the floor when not in use. No damage from forgetting to disconnect. The metal covers were easy to use and the fan would slow down when most were closed so heat was preserved. Best of all, dropping shop rags in the port was no longer a disaster. You’d shut the fan down and (most of the time) the rags would fall into the plenum where you’d fish them out through the hatch. The only real problem occurred when the funnels ends came off the hoses and they got sucked into the ductwork. Fortunately they are too heavy to get sucked up into the fan.

I recommend the underground system. It will probably cost more than $150 though.

BTW – the exhaust hose you describe is the way to go. It takes the hot, moist gasses and drive-over abuse with ease. I had two on my Lightning the other night at my brother’s shop and when I put them away they were HOT, even though his underground system sucks like crazy.

 

I used to plan and design these systems for Uncle Sam. Here's a link to get to a manufacturer. The Company's name is Engwald. They specialize in Industrial and Commercial vehicular exhaust extraction systems. They sell (through distributors)the crush-proof hoses in various diameters and lengths. http://www.engwald.com/

 

I'm looking at buying exhaust hose to accomodate a single or dual exhaust vehicle. The professional grade stuff I've seen on the web is about $40 for 10' of 3", non-crushable hose. Once you get the port for the door, and a tailpipe adapter, you're looking at about $150 worth of stuff.

I want quality materials, and might go ahead and get this, but wanted to see if anyone knows of something better. For example, using PVC, or dryer hose is too cheesy.

Thanks,
LT