An fibrous insulation product is provided that includes a binder comprising a polyol and a phosphorus crosslinking agent derived from a phosphonic or phosphoric acid, salt, ester or anhydride to form crosslinked phosphodiester linkages. The polyol is polyvalent, but may be monomeric or preferably polymeric; and may be synthetic or natural in origin. Carbohydrate polysaccharides are exemplary polyols, including water-soluble polysaccharides such as dextrin, maltodextrin, starch, modified starch, etc. Additionally, the carbohydrate polymer may have a dextrose equivalent (DE) number from 2 to 20. In exemplary embodiments, the binder may also include a catalyst, a coupling agent, a process aid, and other additives. The environmentally friendly, formaldehyde-free binder may be used in the formation of residential and commercial insulation materials and non-woven chopped strand mats. A method of making fibrous products is also provided.