Key Takeaways. Roof insulation costs are fairly consistent, with a low end of $1,000 and a high range of $2,500.The average costs for a typical insulation project are around $2,000.; The materials ...

For every inch of foam roofing, you will add an R-value of 6.5 to 7 to the insulation of your roof. Most foam roofs are done using at least 1 inch of foam. If you want a better insulation value ...