Russell Taylor, good evening,
Looks a lot like Fiber Glass.
As an aside the Asbestos Fiber that does the damage is only several Microns in Diameter,
With respect the Fiber glass you have there is likened to a Rope if compared to a far more dangerous Asbestos Fiber.Diameters.
In general terms, Asbestos was in effect "Outlawed" and prohibited from use, the generally accepted cut off date for Asbestos use in Building Products was the year 2000 [Actual date was late 1999] but the Millennium is easier to remember, at least for the bulk of the General public.
Even before the cut off date above, the technology in roof felt led to the abandonment of Asbestos in the felt in place of a more stable and easier to use Fiber glass, in effect Asbestos incorporation into felt went the same way as Old Horse Hair Felt
As an aside, this type of roofing felt was generally a paper based product with the Asbestos being on the paper base, the base was then coated in the waterproofing layers, thus the Asbestos paper was encapsulated by the waterproofing layers. The product was used generally in flat roofs as a part of a built up system.
Having been at several Asbestos awareness courses, roof felt is very far down on the list to be discussed, being fairly rare?
If you are still uneasy as regards this product or there is a load of it still left In-Situ you could get it tested just or peace of mind.
Ken
