Roofing felt is a common underlayment used in many U.S. roofing systems, and questions about its toxicity affect homeowners, roofers, and environmental regulators. This article examines the materials in roofing felt, potential health risks during installation and disposal, regulatory standards, and safer alternatives to help readers make informed decisions. Key Points:
| Topic | Quick Fact |
|---|---|
| Common Materials | Asphalt-saturated organic or fiberglass mats |
| Primary Risks | Fumes When Heated, Particulate Dust, PAHs Presence |
| Occupational Exposure | PPE Reduces Risk; Ventilation Important |
| Environmental Concerns | Landfill Persistence; Potential Leachate |
| Safer Alternatives | Synthetic Underlayments, Self-Adhered Membranes |
In the United States, roofing materials are regulated at multiple levels, including OSHA for worker safety and EPA guidelines for hazardous waste; ASTM provides product standards. There is no single federal “toxic” designation for standard roofing felt, but components like PAHs are regulated under environmental and occupational statutes.
Testing protocols include GC-MS for volatile organics, PAH panels for semi-volatile compounds, and particulate monitoring for airborne dust. Manufacturers may provide Safety Data Sheets (SDS) that list known hazards and recommended precautions.
Comparing Roofing Felt Types: Organic Vs. Fiberglass Vs. Synthetic
Organic felt is heavier and may contain more cellulosic material; it can release particulate dust and odors when cut or heated. Fiberglass felt is dimensionally stable and resists rot, with generally lower dust generation. Both types are typically asphalt-saturated and share similar hydrocarbon-related hazards.
Synthetic underlayments, made from polypropylene or polyethylene fabrics, offer lower weight, improved tear resistance, and often reduced hydrocarbon emissions. They can be a less toxic option, though additives and manufacturing residues should be reviewed on product SDS sheets.
Safer Alternatives And Product Selection Tips
Synthetic underlayments and polymer-modified self-adhered membranes reduce reliance on asphalt and can lower fumes during installation. Look For products labeled “polypropylene” or “polyethylene” underlayment and check for manufacturer VOC claims.
When selecting products, review technical datasheets and SDS for information on components, recommended installation methods, and disposal guidance. Choosing mechanical fastening over torch-applied systems eliminates a major source of heated fume exposure.
Practical Recommendations For Homeowners And Contractors
Homeowners should ask contractors about the underlayment type, installation method, and safety precautions. Contractors should provide written information about materials and confirm compliance with local building codes and safety practices.
During reroofing, consider ventilating the attic and sealing HVAC intakes to reduce indoor air infiltration of fumes. Scheduling work on cooler days and using mechanical fastening or adhesives rather than torches reduces emissions and fire risk.
Frequently Asked Questions
Is Roofing Felt Carcinogenic?
Roofing felt itself is not labeled universally as a carcinogen, but components like PAHs found in asphalt are associated with increased cancer risk in occupational studies. Risk depends on exposure intensity and duration, so minimizing prolonged inhalation is prudent.
Can Roofing Felt Make Indoor Air Unsafe?
Untreated roofing felt used under shingles typically poses low risk to indoor air after normal installation, but heated or improperly stored materials can emit VOCs that may infiltrate interiors. Proper ventilation and sealing during installation reduce indoor air concerns.
How Should Torn-Off Felt Be Disposed?
Torn-off roofing felt should be handled as construction and demolition waste and disposed of via licensed waste haulers; recycling options are limited but available for some asphalt roofing products. Avoid burning or open-air incineration to prevent toxic emissions.
Resources For Further Information
Authoritative sources include OSHA guidance on asphalt exposure, EPA publications on PAHs, and ASTM standards for roofing materials. Consult manufacturer SDS sheets for product-specific hazard and handling information.
Professional organizations such as the National Roofing Contractors Association (NRCA) provide best practice guidance on safe installation and product selection. Local state environmental agencies can advise on disposal regulations and recycling programs.