There are many things that are designed to reduce drywall dust: airtight, negative-pressure plastic dust barriers; the wet-sanding method (effective only for small areas); and sanding machines that attempt to suck away dust as you sand. They all make admirable efforts, but none is a real match for drywall dust.
Enter low-dust, or dust control, drywall compound (a.k.a. drywall mud). It contains a binder that makes the dust clump into heavier particles so that they fall to the floor rather than... fly through the air. A test-drive of this specialty mud reveals that it works fairly well at reducing the spread of dust, but it's more expensive than standard mud, and it doesn't sand quite as smoothly.
01 of 07
The Enemy: Drywall Dust
Drywall dust is as fine as talcum powder, and it loves to travel. It's also a master escape artist. If you happen to have a hole in your dust barrier the size of a dime, drywall dust will find it and escape. Once out, it will travel farther than you can imagine. An appreciable amount of escaping dust will end up at the other end of the house.
You may think you did a good job of controlling the dust, but you will wake up the next morning and run a finger across your dresser, and your fingertip... will come up white.
02 of 07
Dust Similar to Sawdust
The idea behind dust control mud is that it goes on like regular compound and dries like regular compound, but when it's time to sand it, its special formula makes the dust clump as you sand. The clumps are heavy enough to drop to the floor rather than float into the air like regular powdery sanding dust.
In reality, the dust clumps are similar to sawdust from a jigsaw. If you've ever cut a piece of wood indoors using a jigsaw, you have some of idea of the aftermath of sanding a wall... with dust control mud.
The bulk of the dust piles up at the base of the wall. Then, there is a layer of fine dust radiating out another 2 feet or so. Outside of that is a very fine layer of dust extending to about 10 feet from the wall, with very little dust beyond 10 feet. But compared to the dust from regular mud, this is a noteworthy difference.
03 of 07
You Still Need a Dust Barrier
Using low-dust mud does not mean you can sand drywall with abandon. You'll still need to erect dust barriers if you want to keep the room or surrounding area dust-free. If you do use a barrier, dust control mud will be comparatively less prone to escaping through small holes and seams in the barrier and traveling from one end of the house to the other.
04 of 07
Not a Top-Notch Finish
One advantage of standard drywall mud is its smooth finish. With good mud, you can step down your sandpaper grit, and by the time you have reached the finest grit, the sanded compound is hard and glass-smooth. With low-dust mud, the best finish seems to be only medium-hard and somewhat rougher, a bit short of glass-smooth. Thus, you will not want to use low-dust mud for the final skim coat of a Level 5 drywall finish.Continue to 5 of 7 below.
05 of 07
Slightly Harder to Sand
Perhaps due to the clumping effect that prevents the material from breaking up readily into fine particles, dust control compound seems to be a little harder to sand than standard mud.
06 of 07
More Expensive Than Regular Compound
It should be no surprise that dust-control mud is more expensive than standard all-purpose mud. Pre-mixed, all-purpose joint compound in a 4.5-gallon bucket costs about $15, or $3.33 per gallon. Dust control compound, also pre-mixed, in a 3.5-quart container costs about $8.50, or $9.70 per gallon.
07 of 07
Can Be Swept Up
Another comedy of errors with conventional drywall compound's dust occurs when you try to sweep it up. Every sweep of the broom seems to send more dust airborne than is deposited in the dust pan. This is another reason why it's best to suck it up with a shop vacuum fitted with a drywall dust-compliant bag.
But with low-dust mud, it is possible to sweep up the majority of the pile without creating too much of a dust cloud. Although vacuuming is still recommended.