Floor underlayment is a crucial layer between your subfloor and finished flooring that provides support, moisture protection, and sound dampening.
Choosing the right underlayment can extend the life of your flooring while improving comfort and reducing noise transmission between floors.
This guide compares common underlayment materials to help you select the best option for your specific flooring project.
Types of Floor Underlayment
- Foam Underlayment: Lightweight, affordable option best suited for laminate flooring
- Cork Underlayment: Natural material offering excellent sound insulation and thermal properties
- Rubber Underlayment: Durable choice for high-traffic areas and gym flooring
- Felt Underlayment: Traditional option providing good sound absorption and thermal insulation
- Plywood Underlayment: Rigid support layer often used under vinyl or tile
Comparison Table
| Underlayment Type | Cost per sq ft | Best For | Durability |
|---|---|---|---|
| Foam | $0.25-$0.75 | Laminate, Engineered Wood | 5-10 years |
| Cork | $1.00-$4.00 | Hardwood, Laminate | 20-30 years |
| Rubber | $1.50-$4.50 | Tile, Stone, Gym Floors | 15-20 years |
| Felt | $0.50-$1.50 | Hardwood, Laminate | 10-15 years |
| Plywood | $1.00-$2.00 | Vinyl, Tile | 20+ years |
Moisture Considerations
Always check the moisture content of your subfloor before selecting underlayment (National Wood Flooring Association recommends below 12% moisture content).
- Vapor Barrier Required: Basements, concrete subfloors, crawl spaces
- Moisture-Resistant Options: Cork, rubber, specialized synthetic materials
- Built-in Vapor Barrier: Some foam and felt products include attached moisture protection
Sound Reduction Properties
Sound transmission class (STC) and impact insulation class (IIC) ratings measure noise reduction effectiveness.
- Cork: STC 50-60, IIC 60-65
- Rubber: STC 45-55, IIC 55-60
- Foam: STC 40-50, IIC 45-55
- Felt: STC 45-55, IIC 50-60
Installation Tips
- Clean and level the subfloor before installation
- Allow materials to acclimate for 24-48 hours
- Install vapor barrier if needed before underlayment
- Use manufacturer-recommended seam tape
- Avoid overlapping seams
Making Your Final Choice
Consider your specific needs: moisture protection, sound reduction, thermal insulation, and budget.
- Budget-Friendly: Basic foam underlayment
- Best Sound Control: Cork or rubber underlayment
- Maximum Durability: Plywood or rubber underlayment
- Eco-Friendly: Cork or recycled rubber options
For professional installation assistance, contact the National Wood Flooring Association to find certified contractors in your area.
Maintenance Requirements
- Foam: Replace if compressed or damaged
- Cork: Inspect annually for moisture damage
- Rubber: Clean spills immediately to prevent staining
- Felt: Monitor for moisture accumulation
- Plywood: Check periodically for warping or squeaks
Environmental Impact
Sustainable Options
- Cork: Renewable resource, biodegradable
- Recycled rubber: Reduces landfill waste
- Wool felt: Natural, renewable material
Carbon Footprint Considerations
- Local sourcing reduces transportation emissions
- Look for FSC-certified plywood products
- Choose underlayments with recycled content
Special Applications
- Radiant Heat Systems: Cork or thin foam recommended
- Commercial Spaces: High-density rubber or plywood
- Soundproofing Requirements: Multiple layers of cork or rubber
- Wet Areas: Moisture-resistant rubber or synthetic materials
Making a Long-Lasting Investment
Select underlayment that balances initial cost with longevity and performance. Quality underlayment protects your flooring investment and can reduce long-term maintenance costs. Consider professional installation for optimal results and warranty protection.
- Match underlayment specifications to flooring requirements
- Invest in moisture protection for below-grade installations
- Factor in the total cost of ownership, not just initial price
- Consider future resale value improvements
FAQs
- What are the main types of floor underlayment?
Cork, foam, rubber, felt, plywood, cement board, and moisture barrier underlayments are the primary types available for different flooring applications. - How thick should floor underlayment be?
Floor underlayment typically ranges from 2mm to 6mm in thickness, with most residential applications using 2mm to 3mm underlayment for hardwood and laminate flooring. - Does all flooring require underlayment?
No, not all flooring requires underlayment. Some vinyl planks and tiles come with pre-attached underlayment, while ceramic tile can be installed directly on suitable subfloors. - What’s the best underlayment for soundproofing?
Cork and rubber underlayments provide the best sound reduction properties, with cork offering an STC (Sound Transmission Class) rating of up to 60. - Can I install multiple layers of underlayment?
No, installing multiple layers of underlayment can cause instability in the flooring system and may void manufacturer warranties. - How do I choose underlayment for moisture protection?
Select underlayment with a vapor barrier for below-grade installations or concrete subfloors. Look for products with a minimum vapor permeance rating of 0.5 perms. - What underlayment works best with radiant floor heating?
Thin, dense materials like cork or specialized thermal underlayments conduct heat better than thick foam options, making them ideal for radiant floor heating systems. - How long does floor underlayment typically last?
Quality underlayment typically lasts 20-25 years when properly installed, though its lifespan usually matches the flooring material above it. - Should underlayment be removed when replacing flooring?
Yes, old underlayment should typically be removed to ensure proper installation of new flooring and prevent height issues or deterioration problems. - What’s the average cost of floor underlayment per square foot?
Basic foam underlayment costs $0.25-$0.75 per square foot, while premium options like cork or rubber can range from $0.75-$1.50 per square foot.
