Discover the Surprising Cost of Blown In Insulation Under Floor
Introduction
When it comes to improving your home’s energy efficiency and comfort, few upgrades deliver as much bang for the buck as blown in insulation under floor. By sealing out drafts, reducing heat loss, and preventing moisture buildup, this versatile insulation method can lower your heating and cooling bills and create a more comfortable living environment. In this article, we’ll explore the average cost of blown in insulation under floor, break down the factors that influence pricing, compare it with other insulation types, and answer common questions to help you make an informed decision.
The Average Cost of Blown In Insulation Under Floor
On average, homeowners can expect to pay between $1.50 and $3.00 per square foot for blown in insulation under floor. For a typical 1,000-square-foot area, that translates to roughly $1,500 to $3,000, including materials and professional installation. Your exact cost will depend on several variables:
Material Choices and Their Impact on Cost
• Fiberglass: $0.50 – $1.00 per sq. ft.
– Affordable, fire‐resistant, moisture-tolerant
– R-value around R-2.2 to R-2.7 per inch
• Cellulose: $1.00 – $1.50 per sq. ft.
– Eco-friendly, good soundproofing, treated for fire resistance
– R-value around R-3.2 to R-3.8 per inch
• Mineral Wool: $1.50 – $2.00 per sq. ft.
– Excellent fire and sound resistance
– R-value around R-3.0 to R-3.3 per inch
Labor, Accessibility, and Other Cost Drivers
• Labor Rates: $40 – $70 per hour, varying by region and contractor experience
• Accessibility: Tight crawlspaces, uneven joists and obstructions (pipes, ductwork) can add 10–20% to labor time
• Equipment Rental: Some contractors include it in the quote; DIY rental can cost $100–$200 per day
• Prep Work: Removing old insulation, sealing air leaks, installing vapor barriers can add $0.50–$1.00 per sq. ft.
Factors Affecting the Cost of Blown In Insulation Under Floor
1. Size of the Area
– Larger areas benefit from economies of scale, but total material and labor costs rise proportionally.
2. Condition of Existing Insulation
– If old insulation must be removed or additional repairs are needed, expect an extra $1–$2 per sq. ft.
3. Regional Variations
– Labor and material costs tend to be higher in urban centers or regions with higher living costs.
4. Desired R-Value
– Thicker insulation or higher-performance materials will increase material costs but yield greater energy savings.
5. Contractor Selection
– Licensed, insured professionals may charge more upfront but can prevent costly mistakes and ensure warranty coverage.
Comparing Blown In Insulation Under Floor vs. Other Insulation Types
Blown In Insulation Under Floor
• Pros: Fills gaps and voids, fast installation, high coverage in hard-to-reach areas
• Cons: Requires specialized equipment and professional installer
Fiberglass Batts
• Cost: $0.64 – $1.19 per sq. ft.
• Pros: DIY-friendly, wide availability
• Cons: Challenging to cut and fit in irregular spaces; may leave thermal bridges
Spray Foam
• Cost: $1.50 – $3.50 per sq. ft.
• Pros: Superior air sealing, very high R-value per inch
• Cons: Most expensive; requires specialized applicator and ventilation precautions
Rigid Foam Board
• Cost: $1.00 – $2.50 per sq. ft.
• Pros: High compressive strength, moisture resistance
• Cons: Time-consuming to cut and fit around joists
Q&A
1. What is the ideal R-value for under-floor insulation?
Aim for at least R-19 in mild climates and R-30 or higher in colder regions. Consult local building codes.
2. Can I install blown in insulation myself?
While DIY kits exist, proper technique, protective gear, and specialized equipment are essential. Hiring a professional ensures optimal coverage and performance.
3. How long does blown in insulation last?
Quality blown in insulation can last 20–30 years or more if protected from moisture and pests.
Conclusion
Investing in blown in insulation under floor is a cost-effective way to enhance your home’s comfort, reduce energy bills, and increase resale value. With average costs ranging from $1.50 to $3.00 per square foot, a typical under-floor retrofit will cost between $1,500 and $3,000 for a 1,000-square-foot area—money well spent given the long-term energy savings. By understanding the various materials, labor considerations, and regional factors that influence pricing, you can confidently choose the best solution for your home. Whether you prioritize eco-friendly cellulose, budget-friendly fiberglass, or premium mineral wool, blown in insulation under floor delivers unbeatable coverage and performance for years to come.
