Attic Air Sealing and Insulation Choices
You'll be able to work in your attic if you wear the proper mask. (I use a 3M 6000 series half mask approved for asbestos removal.) Try not to work up there on extremely hot days...you'll sweat a lot and your mask will shift around leaving gaps around your mouth. Wait til night time or cooler weather..
Even still, I would limit the amount of activity and plan on blowing insulation to prevent the amount of movement necessary to accomplish your r-value goals. Blowing insulation is a 2 man job, so you'll need to have a buddy help you out loading the insulation into the blower.
You can use the rental machine that comes free with the insulation. You can get it at the Home Depot or Lowes around here in NJ. You'll have to choose between blown fiberglass and blown cellulose. I like the recycled nature of cellulose, so I usually take that path, but blown fiberglass does a fine job.
Air sealing is the process of installing caulk, expanding foam, sheet metal, foam board and gaskets to prevent air from flowing through the walls, floors and ceilings in your home.
35% of your heat and air conditioning is lost through holes, gaps and cracks left in your home by the electricians, plumbers, HVAC installers and framers. No amount of fiberglass insulation will stop air from being sucked out of your house by the winter winds, but air sealing will...
The main problem you have is that in order to properly air seal your attic floor, you need to remove the insulation...
If you want to dramatically lower your energy bills and make your home a lot more comfortable, this is the way to go. It's also the most expensive route. But the heating oil $4/gallon it might pay off in a few years. After all, most of the heat in your home rises and escapes through your attic.
There are less expensive ways to dramatically lower your energy bills, but I'm running out of time right now...