New insulation can be installed on top of old insulation in some cases, but there are times when insulation should be removed completely before replacement. An insulation professional will be able to assess your insulation and determine whether or not it needs to be removed. But in general, you’ll need insulation removal services when your insulation is:

Infested by rodents

Damp or wet

Moldy

Damaged by fire or anything else

Also, according to ENERGY STAR, any vermiculite insulation (which is more likely to have asbestos) should be tested and, if asbestos is present, professionally removed.

If insulation is damaged by water, mold, fire, rodents or anything else, it won’t be as effective at stopping heat transfer and maximizing the energy efficiency and comfort of your home or building. This is why it’s important to make sure your insulation is in good condition and will work the way it’s supposed to.