During the past year I know I have read recommendations on using a paintable water sealer on exterior joined wood before priming and painting. We're prepping areas of a nice 1960's house in order to repaint areas where weather and water have caused the wood to reject the paint (common problem with age on oil primer). The house has wood panels as a decorative element below the windows that could use some water seal. But the owner of the house has never heard of using a water seal on exterior wood under primer and would allow us to do this only if someone like Bob Villa said so (according to his wife). Does anyone else recall the five year trial that matched sealed versus unsealed exterior wood on an historic restoration? How can I convince the man that water seal is right in this case, and does anyone have a favorite brand to use under paint. Personally, I've used water seal under paint occasionally for year and now frequently since hearing the recommendations. But my word isn't good enough. Maybe a reply on this message board would do the trick.