One of the most common remodeling jobs I get asked to do is replacing entry doors. These jobs often involve hanging a new door in an existing opening. One of the sticky spots on these rehanging jobs is creating a good weatherseal between the old jambs and the new door. On a recent job, I tried caulk-in tubing from Conservation Technology to make a pair of custom entry doors weathertight.

Available in five diameters for gaps ranging from less than 1/8 in. up to 3/8 in., the silicone tubing is available in white or bronze and costs between 36¢ per ft. and 96¢ per ft. The tubing is also available in 100-ft. rolls. After a bead of neutral-cure silicone caulk (Dow 795 or GE Silicone II are two options) is applied, the tubing is pressed into place.

Once cured, which the company says can take as little as an hour, the tubing will be permanently seated. My advice: Do the installation on a nice warm day, and give the silicone at least a few hours, if not overnight, to fully cure. I didn’t wait long enough on the first door and ended up with silicone smeared all over the door’s hinge side.

The cool thing about this system is that you can use tubing of different diameters on different parts of the same installation, or even double up on thicknesses where needed. The tubing is extremely compressible; if installed appropriately, it won’t make closing the door any more difficult.

I don’t think these caulk-in seals are the best solution for sealing every job, but they are handy for situations where nail-on or cut-in weatherseals aren’t practical or pleasing to the eye.