We have a 70 yr old house (in Long Island) with hardwood floors that are cold in the winter and allow cold air to seep in around the perimeter (under the heating elements). I put a bead of silicon seal around obvious cracks and now need to do something under the house.
The previous owners put insulation in the crawl space between the joists - but put it in upside down. There is also no vapor barrier on ground, just dirt. The 4 ventilation "vents" were covered by another piece of wood, but the crawl space is definitely not "air tight".
Since I am 6'9", getting through this small opening and working with 2 feet clearance, I'd like to do this project in as few steps as possible! The house definitely loses a lot of heat and my questions are:
1) Do I remove all the insulation that is installed "kraft-side down" and put new insulation in the correct way? (about 1,000 square feet)
2) Should any material be installed between the insulation and "ceiling" of crawlspace?
3) Do I need to put down plastic sheeting on the dirt?
4) How do I ensure that I cover the cracks that leak air around the perimeter of my hardwood flooring?
3- It's a good idea, and tape the seams.
4- If you can reach them with a spray foam from underneath then use that. Foam is better than caulking 'cos it not only stops air but provides some r-value too. And it expands into places you can't reach with a caulking gun.