Planning to put in ceramic tile or a new wood floor? You might have to shorten the casing around your door so the new tile or flooring can slide in beneath it. What's the easiest way to get this done? Pros use a piece of the new flooring as a measurement guide to determine exactly how much casing needs to be trimmed so that it can slide in below while still providing a snug fit. Measuring is OK, but using the actual material as a guide works even better. Just turn it over to keep from scratching the face, and lay a handsaw on top of the material. Using the flooring as a thickness guide, saw off the bottoms of the casing on each side. Remove the “waste” cuts and the flooring material, and the casings will be exactly the right height to accept the new flooring beneath it. It'll be snug and tight because it was measured and cut just right. And that's the On The House tip for today.