This GreenFiber blow-in natural fiber insulation is engineered for use in wall and attic retrofit projects to help homeowners take advantage of federal tax credits. It’s made with an all-borate fire-resistant formula that offers a higher level of dust suppressant for re-insulation applications. Made from 85 percent recycled paper fibers, it offers R-values from 13 to 60. Cost: under $12 per bag. GreenFiber. 800-228-0024.