There are many different kinds of wool like insulation that are man made and do not have asbestos but if your attic insulation looks like wool than it is best to be safe and have it tested by a professional.
Old attic insulation asbestos.
In this austin texas home the vermiculite was hiding beneath blown cellulose insulation.
Fiberglass and cellulose are the most common insulation installed in residential attics today.
But the vermiculite that was mined years ago was contaminated with an asbestos like material.
There is one type of older insulation that has a significant possibility of being contaminated with asbestos.
Asbestos is actually a natural fiber so if your attic insulation looks like wool there is a slight chance that it will contain asbestos.
See this article on vermiculite and asbestos for more information.
In older homes specifically asbestos may be found in many different materials from pipe insulation to flooring adhesive to roof shingles.
It is often used for gardening and as insulation in older homes.
That is the loose granular insulation called vermiculite.
Geological survey vermiculite attic insulation is sometimes found in older homes and is often contaminated with asbestos because of the libby montana mine where it originated.
Asbestos can be found in the insulation used in walls attics the materials around plumbing and pipes electrical wiring as well as on heating and air conditioning units.
But just because your insulation is old doesn t mean it is dangerous.
In its essence vermiculite is pellet like material that expands at high temperatures.
If your insulation is in batt form you shouldn t worry.