Fiberglass Insulation Guide for Franklin Homeowners | 2025 Edition

Fiberglass insulation remains one of the most popular and cost-effective insulation options for Franklin homeowners. Understanding its benefits, applications, and proper installation helps you make informed decisions about improving your home's energy efficiency and comfort.

Fiberglass insulation consists of fine glass fibers arranged to trap air pockets, creating thermal resistance. Available in various forms and R-values, fiberglass insulation has protected homes for decades, offering reliable performance at affordable prices.

The material is manufactured from recycled glass (often 40-60% recycled content) and sand, making it an environmentally conscious choice that doesn't compromise performance.

Fiberglass Batts and Rolls

Pre-cut sections or continuous rolls designed to fit between standard wall studs, floor joists, and ceiling joists:

• Available in standard widths (15" and 23")
• Various thicknesses providing R-13 to R-38
• Faced (with vapor barrier) or unfaced options
• Cost-effective for new construction and accessible retrofit projects
• Requires proper installation to avoid gaps and compression

Blown-In Fiberglass

Loose-fill fiberglass installed pneumatically:

• Excellent for attics and hard-to-reach spaces
• Fills around obstacles and irregular areas
• Achieves consistent coverage without gaps
• Ideal for retrofit applications
• Settles less than cellulose insulation

Blown-in fiberglass provides superior coverage in existing attics where batts would be difficult to install properly around trusses, wiring, and other obstacles.

Cost-Effectiveness

Fiberglass insulation delivers excellent value, providing effective thermal resistance at lower cost than spray foam or rigid foam alternatives. For budget-conscious Franklin homeowners, fiberglass offers the best performance-to-price ratio.

Fire Resistance

Naturally non-combustible, fiberglass insulation won't burn and doesn't require fire-retardant chemical treatments. It actually slows fire spread and provides critical additional escape time during emergencies.

Moisture Resistance

Unlike cellulose, fiberglass doesn't absorb moisture or promote mold growth. While it doesn't provide moisture barriers, the material itself remains effective even when exposed to humidity.

Sound Dampening

Fiberglass effectively reduces sound transmission between rooms and from outside, improving your home's acoustic comfort. It's particularly valuable in bedrooms, home offices, and media rooms.

Longevity

Properly installed fiberglass insulation lasts 80-100 years without significant degradation, settling, or loss of R-value. It's a true long-term investment in your home's efficiency.

Environmentally Friendly

Made largely from recycled glass and requiring less energy to manufacture than many alternatives, fiberglass insulation supports sustainable building practices.

Attic Insulation

Both blown-in and batt fiberglass work excellently in attics. Blown-in fiberglass provides easier installation and better coverage in existing attics, while batts work well during new construction or when attic floors are clear.

Franklin homes should target R-49 to R-60 attic insulation for optimal performance in Tennessee's climate. Learn more about comprehensive attic insulation solutions.

Wall Insulation

Fiberglass batts fit perfectly between standard 2x4 or 2x6 wall studs, providing R-13 to R-21 values respectively. Proper installation without gaps or compression is critical for maximum effectiveness.

Floor Insulation

Fiberglass batts between floor joists above crawl spaces or unheated basements prevent cold floors and reduce heating costs. Installation must include proper support to prevent sagging.

Cathedral Ceilings

High-density fiberglass batts work well in cathedral ceilings when installed with proper ventilation channels maintaining airflow between insulation and roof decking.

Crawl Space Applications

When insulating crawl space ceilings rather than walls, fiberglass batts provide cost-effective solutions. However, proper moisture management and installation support are essential.

R-value measures insulation's thermal resistance—higher numbers indicate better insulating properties. For Franklin, Tennessee:

Attics: R-49 to R-60 recommended
Walls: R-13 to R-21 depending on stud depth
Floors over unconditioned spaces: R-25 to R-30
Crawl space walls: R-13 minimum if using wall insulation approach

These values exceed minimum code requirements but provide better comfort and energy savings, typically paying for themselves within 5-7 years.

When Professional Installation Makes Sense

Hire professionals for:

• Blown-in fiberglass applications (requires specialized equipment)
• Large-scale projects
• Areas requiring air sealing before insulation
• Situations involving electrical, plumbing, or HVAC modifications
• When you lack time, tools, or comfort with the work

Professional installation ensures proper R-values, complete coverage, and compliance with building codes.

DIY Considerations

Batt insulation installation can be DIY-friendly for:

• Small, accessible areas
• Homeowners comfortable with physical work
• Projects with straightforward layouts
• When budget is extremely tight

However, improper installation reduces effectiveness significantly. Gaps, compression, and inadequate coverage compromise performance, potentially negating any cost savings.

Quality fiberglass installation requires:

Air Sealing First

Seal gaps, cracks, and penetrations before installing insulation. Air leakage undermines insulation effectiveness, so addressing it first maximizes performance.

Proper Fit Without Compression

Fiberglass must maintain its full thickness to achieve rated R-values. Compressing it into spaces reduces effectiveness proportionally. Split batts to fit around obstacles rather than compressing.

Continuous Coverage

Eliminate gaps at edges, corners, and around obstacles. Even small gaps significantly reduce overall effectiveness.

Correct Facing Orientation

When using faced insulation, install with the facing toward the warm-in-winter side (typically toward living spaces). Ensure facings overlap properly at seams.

Ventilation Maintenance

In attics and cathedral ceilings, maintain proper ventilation. Use baffles ensuring airflow from soffit vents to ridge vents isn't blocked.

Safety Equipment

Wear protective equipment including dust masks, gloves, long sleeves, and eye protection. Fiberglass particles can irritate skin, eyes, and lungs during installation.

Fiberglass insulation costs vary based on:

• Insulation type (batts vs. blown-in)
• R-value selected
• Square footage
• Accessibility and preparation needed
• DIY vs. professional installation

Typical Costs:

• Batt insulation materials: $0.40-$1.00 per square foot
• Blown-in fiberglass materials: $0.30-$0.80 per square foot
• Professional installation: adds $1.00-$2.50 per square foot
• Complete attic insulation project: $1,500-$3,500

Fiberglass provides excellent value, typically delivering the lowest cost per R-value of any insulation type.

Fiberglass vs. Cellulose

• Fiberglass resists moisture better
• Cellulose settles more over time
• Similar R-values and costs
• Fiberglass is more fire-resistant without treatments

Fiberglass vs. Spray Foam

• Spray foam costs 2-3 times more
• Spray foam provides superior air sealing
• Fiberglass allows easier access to wiring and plumbing
• Both offer long lifespans

For more information about spray foam options, explore spray foam insulation benefits.

Fiberglass vs. Rigid Foam

• Rigid foam provides higher R-value per inch
• Rigid foam costs more
• Fiberglass works better for cavities (walls, floors)
• Rigid foam excels for exterior continuous insulation

Compressing Insulation: Reduces R-value proportionally to compression

Leaving Gaps: Even small gaps significantly reduce effectiveness

Covering Recessed Lights: Creates fire hazards unless lights are IC-rated

Blocking Ventilation: Causes moisture problems and reduces insulation lifespan

Wrong Facing Direction: Reduces moisture control effectiveness

Inadequate R-Values: Installing minimum code requirements rather than optimal levels

Fiberglass insulation requires minimal maintenance but benefits from periodic inspection:

• Check for damage from pests, moisture, or disturbance
• Verify coverage remains complete without gaps
• Ensure ventilation systems continue functioning
• Look for signs of roof leaks or moisture problems
• Inspect after major home renovations or repairs

Properly installed and undisturbed fiberglass insulation lasts the lifetime of your home.

Franklin's historic charm includes many older homes built before modern insulation standards. Properties from the 1970s-1990s often have R-19 to R-30 attic insulation—adequate when installed but below current recommendations for optimal performance.

Upgrading to R-49 to R-60 provides significant comfort improvements and energy savings, with many homeowners seeing 20-30% reductions in heating and cooling costs.

Franklin's premium real estate market values energy-efficient homes. Proper insulation upgrades add resale value while improving comfort during ownership.

The city's mature tree canopy provides natural cooling but increases humidity levels during summer. Fiberglass insulation's moisture-resistant properties perform well in these conditions when combined with proper ventilation.

Williamson County building codes enforce specific insulation requirements for new construction and major renovations. Professional installers familiar with local requirements ensure compliance and smooth inspection processes.

Franklin homeowners may qualify for:

• Federal tax credits for energy efficiency improvements
• Utility company rebates for insulation upgrades
• Low-interest loans for energy efficiency projects

Professional contractors can help identify available incentives and ensure your project meets qualification requirements.

Fiberglass insulation offers Franklin homeowners reliable, cost-effective thermal performance. Whether upgrading existing insulation or insulating new construction, fiberglass delivers excellent value and long-lasting results.

Black Oak Insulation & Gutters provides professional fiberglass insulation installation throughout Franklin and Williamson County. Our experienced team ensures proper installation maximizing your insulation investment's performance and longevity.

Ready to improve your home's comfort and efficiency? Contact Black Oak Insulation & Gutters at (629) 310-7393 for a comprehensive home assessment and detailed estimate customized to your specific needs and goals.