Vapour barrier to prevent dust?

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I'm in the midst of redoing the lights in my MRR room, and am considering installing sheets of vapour barrier on the joists, above the lights to prevent dust from coming from the floor above. Considering how much dust I'm already generating in the room, would this stop very much at all? I've heard that a lot of dust can come from above floords, but does anyone have experience with this type of thing?


Master Mechanic
Installing vapor barrier above a layout to catch dust is a good idea. But one thing you'll have to watch for is condensation between the vapor barrier and the joists/floorboards above it. The plastic would be at a slightly cooler temperature that the surrounding air and condensation could be a problem. The solution of course would be to just make sure that each end of the plastic is open to allow for circulation of the air thru the "runways" between the joists, the plastic would provide.

In simple terms, if the room is 12' wide, only apply the plastic on the middle 11' of the area, leaving an open 6" at each end allowing for the air to circulate. This would catch 99% of the dust and allow for air circulation which would prevent condensation.
In my rifle/reloading room I used plastic barrier and it was amazing how much dust it stopped. Most dust does come through the flooring from above unless you are leaving basement windows open. I went from having to dust my collection every day to doing it once or twice a month. I lived in Utah though so the humidity was not a concern.

Have you given thought to renting a paint sprayer and hitting the joists/sub floor with 8-10 good coats of interior paint to seal the wood and keep dust from migrating through? You wouldn't have to worry about trapping the humidity this way and it would be a cleaner look. is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to - An online railroad bookstore featuring a curated selection of new and used railroad books. Railroad pictorials, railroad history, steam locomotives, passenger trains, modern railroading. Hundreds of titles available, most at discount prices! We also have a video and children's book section. - An online model railroad bookstore featuring a curated selection of new and used books. Layout design, track plans, scenery and structure building, wiring, DCC, Tinplate, Toy Trains, Price Guides and more.