If your home isn’t retaining heat like it used to, it's probably time to add new attic insulation. Mostly the old insulation should be left in place. Even if it’s crappy, it doesn’t interfere with the new material and will even contribute to the R-value, even if only by a factor of 1 or 2.
There are certain instances, particularly mold issues or other contaminations, where the insulation should be removed for health safety reasons. This process can be laborious and last for a day or two, but the following steps should make the task easier.
Rake and Remove Blown Attic Insulation
To remove the bulk of the blown attic insulation, the best method is to use a rake to scrape the insulation together and stuff it into trash bags. Wear long pants, work gloves, and a face mask to prevent any contact or inhalation of dust and debris. Remember that the job will go even faster if you can get an extra pair of helping hands!
Vacuum up the Remains
Once the bulk of the blown attic insulation has been removed, use a commercial vacuum to suck up the remaining bits and pieces of insulation. Don’t attempt the entire job with a vacuum, as the hose can easily get clogged and the vacuum would need to be constantly emptied during the course of the operation. Again, this part of the task will go faster with a helper to empty the vacuum and clear debris from the hose as you work.