Planning a big do-it-yourself project this weekend? Before you start, prepare for a big mess. Remodeling, repairs and home improvements all have one thing in common. They often produce lots of dirt and dust that works its way into every nook and cranny -- in every part of your house. This is why, for both airborne minute particles and those particles spread by foot traffic, you must take measures ahead of time or pay the piper later. Two new items we like are plastic film-runners with a light, tacky underside that stays put underfoot, and temporary pre-fab work-site enclosures. They're created by wrapping plastic film around floor-to-ceiling extension poles. To get in and out, 8-foot-long zippers with peel-and-stick backing are put in place, then zipped open. The plastic is slit with a razor knife to create a walk-through closeable entry point. The name? Zip wall (which makes sense). Products like these, as well as closing or sealing air vents, go a long way toward household mess-prevention. And that's the On The House tip for today.