Roofing felt, also called tar paper or underlayment, is a foundational material used to provide a moisture barrier beneath shingles or metal roofing. Its price depends on type, weight, length, and width. This guide breaks down common roofing felt options, typical roll sizes, and current U.S. price ranges to help homeowners estimate costs for projects large and small.
Types Of Roofing Felt
Understanding the main varieties helps align budget with performance. The two most common categories are asphalt-saturated felt and self-adhering (torch- or cold-applied) underlayment. Asphalt-saturated felt is inexpensive and widely used on traditional roofs, while self-adhering underlayment offers superior waterproofing and easier installation in some climates.
- 15-pound asphalt-saturated felt: The standard, budget-friendly option. It provides a basic moisture barrier and is widely used in new roofs and re-roofs on moderate climates.
- 30-pound asphalt-saturated felt: Heavier, more tear-resistant and durable than the 15-pound version. It provides longer life in harsh weather and is favored on steeper or higher-wear roofs.
- Self-adhering underlayment: Also called self-adhesion or peel-and-stick. It typically has an asphalt or synthetic membrane with adhesive that sticks to the roof deck. It offers enhanced waterproofing, especially in valleys, eaves, and roof transitions.
Typical Roll Sizes And Coverage
Roll dimensions influence cost, handling, and waste. The most common roofing felt rolls in the United States are 36 inches wide, with lengths ranging from about 90 to 100+ feet. Coverage per roll is roughly 270 to 360 square feet, depending on the exact length.
- 36″ wide by 90–100 feet long: Approximately 270–300 square feet per roll.
- 36″ wide by 100–120 feet long (self-adhering or premium options): Approximately 300–360 square feet per roll.
When calculating materials, consider extra rolls for waste and overlaps. Valleys, roof edges, and difficult-to-fit shapes may require additional material beyond the straight square footage.
Price Ranges By Type
Prices vary by weight, adhesive technology, and supplier. The figures below reflect typical retail prices in the United States as of the latest market data and may fluctuate with regional differences and fuel costs.
- 15-pound asphalt-saturated felt: Commonly $20–$40 per roll. A typical roll covers about 270–300 square feet, giving a cost per square foot around $0.07–$0.15.
- 30-pound asphalt-saturated felt: Generally $40–$70 per roll. Coverage is similar, around 270–300 square feet, with a cost per square foot near $0.13–$0.26.
- Self-adhering underlayment (peel-and-stick): Usually $60–$120 per roll. Coverage ranges from 270–360 square feet, resulting in roughly $0.17–$0.44 per square foot.
Notes on pricing: higher weight felts and self-adhering types cost more upfront but may reduce labor time and improve performance in wet climates. Bulk purchases and regional supply chains can affect overall pricing. Expect price variations based on brand, warranty, and whether you buy loose or as part of a roofing package from a contractor or home improvement retailer.
Factors Affecting Price
Several factors influence the bottom line beyond the basic weight and type. Being aware of these helps homeowners forecast total project costs more accurately.
- Roll length and width: Longer rolls reduce waste but may have higher upfront costs. Widths other than 36″ are available in specialty products.
- Material composition: Asphalt-saturated felt is cheaper than synthetic or all-weather composite underlayments, and self-adhering products command a premium for adhesive features.
- Climate and installation requirements: Regions with heavy rain, snow, or ice dam risk may favor self-adhesive or premium underlayments, raising price but potentially saving labor and future repairs.
- Brand and warranty: Reputable brands with longer warranties may cost more but offer added assurance and performance.
- Acquisition method: Buying from a hardware store, local distributor, or roofing contractor can create price differentials due to bulk pricing, pickup vs. delivery, and service charges.
Where To Buy And How To Compare
Americans typically source roofing felt from home improvement centers (like Home Depot, Lowe’s), building supply distributors, or roofing specialty outlets. Compare quotes by considering:
- Price per roll and total rolls needed for the project
- Coverage accuracy based on roll length and width
- Warranty and code compliance with local building codes
- Installation considerations such as weight, ease of handling, and compatibility with chosen roofing material
- Delivery options for large orders, particularly in rural areas
For projects with complex roof lines, obtaining a rough material list from a contractor or using a professional estimator can prevent material shortfalls and waste, optimizing the overall cost.
Installation Considerations And Practical Tips
Price is only part of the equation. Proper installation ensures performance and durability. Here are practical guidelines to keep costs predictable and ensure a quality job.
- Inspection and deck preparation: Before laying felt, inspect the roof deck for damage, nails, and moisture. A clean, dry surface improves adhesion and reduces future repair costs.
- Weather window: Install underlayment in dry weather; moisture can compromise adhesion for self-adhering products and reduce effectiveness for asphalt-saturated felts.
- Overlaps and fastening: Follow manufacturer recommendations for overlaps (commonly 2-4 inches for felt) and fastening methods (nails or staples) to avoid gaps.
- Ventilation and flashing: Ensure proper ventilation and correct flashing integration with underlayment to prevent leaks and prolong roof life.
- Safety and handling: Manage rolls safely to prevent injuries and damage to roof edges.
Smart budgeting tip: For a standard shingles roof of about 1,500–2,000 square feet, estimate roughly 5–6 rolls of 36″ by 90–100 feet for 15-pound or 30-pound felt, and consider 6–8 rolls if self-adhering underlayment is preferred or required by code. Always round up to cover waste and unusual shapes.