I’m a NJ homeowner (I guess that makes me rich, at least by congressional budget office standards) and am planning a renovation to my 1962 vintage ranch (as in ranch style home, not Crawford, TX type).  I have a 12′ X 14′ room off of my otherwise rectangular residence that is over a crawl space.  I also have a 10′ X 26′ one car garage (now known as a shed) at the end of the home.  My renovation will have the 12 X 14 room (plus a new 6′ X 6″ crawlspace) become the kitchen and the existing garage become living space.  My architect has recommended venting the crawl spaces into the existing basement area to condition the air and avoid moisture problems, pipes freezing, etc.  I basically agree with this idea, but have two questions on the best way to prevent outside air and moisture from entering these areas. Since the “new” Kitchen will be over the existing crawl space, I am wondering what improvements I can make to insulate, add vapor barrier, etc.  I am planning on lifting the subfloor to gain access and want to take the opportunity to do it right the first time.  I am looking for some suggestions from the experienced gang here at breaktime forum.  I would also like your thoughts on the living space over my existing garge floor.  The new floor level will be about 13-14 inches above my existing garage floor (concrete slab) so I need to make the most of this space.  What type of vapor barrier should I consider?  How much insulation and what type.  I will have plumbing into both spaces for the kitchen and a 1/2 bath also. I would like not to have to lift my new tile work and subfloor due to mold, mildew, leaky pipes, and so on. I’m considering radiant floor heat, but I’ll save that for another post! Thanks for your willingness to help and time to respond to help a longtime fine homebuilding reader, but relatively new GC.