Afterburner on my----Vacuum Cleaner????

Well, not really an afterburner, but----My house has one of those built in vacuum cleaners that is mounted on my garage wall, on the inside.(garage is attached to house). The exhaust just blows out into the garage, and even with a freshly cleaned filter pad and everything else, it blows out a very fine, greasy dust out the air discharge into the garage space---and the RPU has a white convertible top---Oh Yeah!!!! On my previous house I had the same situation and fixed it by running 2" diameter ABS piping from the air discharge out thru the brick wall---Only trouble was, I almost broke my wrist drilling thru the brick wall with a 2" core drill. Not wanting to repeat that particular injury, I did a bit of research this morning, and found out that you can buy an "after-filter", built exactly for the purpose I need. It hooks to a 2" diameter pipe which attaches to the discharge side of the vacuum cleaner. For $18, it may be just the thing I needed. I thought all the others out there with a similar problem might like to know about this.---Brian