Insulation Types: The Complete Guide
Discover the best insulation for your home. Compare fiberglass, spray foam, cellulose, mineral wool, and rigid foam to make an informed decision for your project.
Why Insulation Matters: Proper insulation is one of the most important investments you can make for your home. It reduces energy costs, improves comfort, and protects your property from moisture damage and extreme temperatures. This guide covers everything you need to know about insulation types, R-values, installation, and costs.
Understanding R-Value
R-value measures thermal resistance — the ability of insulation to resist heat flow. Higher R-values mean better insulation performance. The recommended R-value for your home depends on your climate zone, the part of the house being insulated, and your local building codes. For most homes, attic insulation requires the highest R-values (R-38 to R-60), while walls typically need R-13 to R-21.
Common Insulation Types
Fiberglass
The most common and affordable insulation option.
- Available in batts, rolls, and loose-fill
- Good thermal and acoustic performance
- Non-combustible and moisture-resistant
• DIY-friendly
• Widely available
• Less effective if compressed
• Requires careful installation
Spray Foam
Superior air-sealing and insulation in one application.
- Open-cell and closed-cell options
- Expands to fill gaps and cracks
- Excellent for attic insulation and crawl spaces
• Air-sealing properties
• Adds structural strength
• Requires professional install
• Off-gassing during application
Cellulose
Eco-friendly insulation made from recycled paper.
- Loose-fill or dense-pack application
- Excellent for retrofits and attic insulation
- Good soundproofing properties
• Good fire resistance
• Pest-resistant (borate-treated)
• Moisture-sensitive
• Requires special equipment
Mineral Wool
Excellent for soundproofing and fire resistance.
- Made from rock or slag wool
- Naturally fire-resistant
- Great for soundproofing walls and floors
• Excellent soundproofing
• Water-repellent
• Heavier to install
• Can irritate skin
Rigid Foam
High-performance insulation for exterior walls and foundations.
- Polyiso, EPS, and XPS options
- Moisture-resistant and durable
- Ideal for exterior sheathing and basement walls
• Moisture-resistant
• Adds structural support
• Requires precise cutting
• Flammable (must be covered)
Reflective / Radiant Barrier
Reflects radiant heat, ideal for hot climates.
- Foil-faced paper or plastic
- Reduces cooling costs in summer
- Effective in attic insulation applications
• Lightweight and easy to install
• Can be combined with other insulation
• Not effective in cold climates
• Requires air space to work
Insulation Types Comparison
| Type | R-Value per inch | Cost per sq. ft. | Best Application | Installation |
|---|---|---|---|---|
| Fiberglass | R-2.2 – R-4.3 | $0.30 – $1.50 | Walls, Attics, Floors | DIY / Professional |
| Spray Foam | R-3.5 – R-6.5 | $1.00 – $3.00 | Attics, Crawl Spaces, Walls | Professional Only |
| Cellulose | R-3.2 – R-3.8 | $0.50 – $1.20 | Attics, Retrofits | Professional / DIY |
| Mineral Wool | R-3.0 – R-3.3 | $0.80 – $2.00 | Soundproofing, Fire-Rated Walls | DIY / Professional |
| Rigid Foam | R-3.6 – R-5.0 | $1.50 – $3.50 | Exterior Walls, Basements | Professional / DIY |
| Radiant Barrier | R-1.0 – R-2.0 | $0.50 – $1.50 | Attics (Hot Climates) | DIY |
💡 Insulation Installation Tips
- Safety First: Always wear protective gear including gloves, safety glasses, and a respirator when handling insulation materials.
- Air Seal First: Seal all air leaks with caulk or spray foam before installing insulation for maximum effectiveness.
- Don't Compress: Never compress insulation — it reduces R-value and performance.
- Consider Vapor Barriers: In cold climates, install a vapor barrier on the warm side of insulation to prevent moisture problems.
- Leave Attic Access: Keep attic access points clear and consider adding a attic insulation cover or hatch to maintain R-value.
How to Choose the Right Insulation
Selecting the right insulation type depends on several factors including your climate, budget, the area being insulated, and your DIY comfort level.
🏠 By Location
Attic: Spray foam, cellulose, or fiberglass
Walls: Fiberglass batts, spray foam, or cellulose
Basement: Rigid foam or spray foam
Floors: Fiberglass or mineral wool
💰 By Budget
Low: Fiberglass batts, cellulose loose-fill
Medium: Mineral wool, rigid foam
High: Spray foam (closed-cell)
🔧 By DIY Level
Beginner: Fiberglass batts, reflective barriers
Intermediate: Mineral wool, rigid foam
Professional: Spray foam, dense-pack cellulose
Related Home Improvement Considerations
When planning insulation upgrades, consider these complementary home improvement projects that can further enhance your home's efficiency and comfort.
Maximize energy savings
SoundproofingReduce noise between rooms
Home SafetySafety during installation
Mold RemediationAddress moisture issues first
Seasonal MaintenancePrepare your home year-round
Emergency RepairsHandle unexpected issues
Frequently Asked Questions
Ready to Improve Your Home's Insulation?
Browse recommended insulation products below to find the best solution for your home.
SHOP INSULATION PRODUCTS