Comprehensive contractor guide breaking down attic insulation costs by material type (fiberglass, spray foam, cellulose), regional pricing variations, DIY vs professional installation, and hidden costs. Includes cost estimates ranging from $1.50-$5.50 per sq ft with ROI analysis and money-saving tips for homeowners and contractors. https://quantifyna.com/how-much-does-it-cost-to-insulate-an-attic/