When it comes to maintaining the integrity and longevity of your roof, one of the most critical components that should not be overlooked is roof felt. Whether you’re replacing an old roof, undertaking a roofing project, or repairing an existing roof, buying the right felt for your roof is essential. Roof felt acts as a protective barrier, preventing moisture from seeping into the structure, thus keeping your home dry and safe. In this article, we will delve deep into everything you need to know about buying felt for your roof, from its purpose and types to installation tips and factors to consider before making a purchase.

What is Roof Felt and Why is It Important?

Roof felt, also known as roofing felt, is a roll of material used as an underlayment for roofing systems. It is typically placed between the shingles or tiles and the decking (the wooden surface beneath your roof covering). The primary purpose of roof felt is to act as a secondary layer of defense against moisture, wind, and other elements that could damage the roofing structure.

Roof felt serves as a water-resistant barrier, ensuring that if water penetrates the outer layer of roofing materials, it doesn’t reach the underlying wood or insulation. This is especially important in climates with heavy rainfall, snow, or humidity, where roofing materials are more vulnerable to water damage. The felt also helps in preventing mold growth, rotting of the decking, and rust formation on metal roofing materials.

In addition to protecting against water, roof felt can also serve as an insulator by adding a layer of thermal resistance to your roof. It helps to maintain temperature regulation inside your home, reducing the need for excessive heating or cooling. This contributes to energy efficiency, making your home more comfortable throughout the year.

Types of Roof Felt: Choosing the Right One for Your Roof

When buying felt for your roof, it’s crucial to understand the different types available. Roof felt comes in various materials and grades, each designed for specific applications, and selecting the right one will ensure your roof performs optimally over time. The two primary types of roof felt are asphalt felt and synthetic felt, but there are several variations within these categories.

Asphalt Felt

Asphalt felt is the traditional material used for roofing felt. It is composed of a fibrous base, typically made from organic or fiberglass matting, that is then saturated with asphalt. Asphalt felt is known for its durability and water-resistant properties, which is why it has been the go-to material for centuries. It comes in different weights, such as 15-pound and 30-pound felt, with the number representing the weight of a single 100-square-foot roll.

• 15-pound felt is lightweight and commonly used in dry climates or as an underlayment for shingles.
• 30-pound felt is heavier and provides better durability, making it suitable for areas with high moisture or wind exposure.

Asphalt felt is a tried-and-true material, but it does have some downsides, such as being more prone to tearing and degradation under extreme weather conditions. Over time, asphalt felt can become brittle and break down when exposed to UV rays or moisture for extended periods.

Synthetic Felt

Synthetic felt is a modern alternative to asphalt felt, made from advanced materials like polyester or polypropylene. These materials offer superior strength, water resistance, and durability compared to traditional asphalt-based felt. Synthetic roof felt is generally more lightweight, which makes it easier to handle during installation.

One of the biggest advantages of synthetic felt over asphalt is its UV resistance. Unlike asphalt, which can break down and degrade under UV exposure, synthetic felt maintains its integrity and performance for much longer, even in harsh conditions. Synthetic roofing felt is also more resistant to tearing, and some products come with built-in anti-microbial properties to prevent mold and mildew growth.

In addition to its durability, synthetic felt typically has a higher breathability than asphalt, meaning it allows more airflow beneath the roofing materials. This can help to prevent the buildup of moisture that could lead to mold growth or other structural issues.

Factors to Consider When Buying Felt for Your Roof

Now that you’re familiar with the different types of roofing felt, it’s essential to consider several factors before making your purchase. The right choice depends on your specific roofing needs, the climate in which you live, and the type of roofing material you’re using. Below are key factors to take into account when selecting the right felt for your roof.

1. Climate and Weather Conditions

The climate in your region plays a significant role in determining the best type of roof felt for your home. If you live in an area prone to heavy rainfall, snow, or humidity, you’ll need a roofing felt that offers excellent water resistance. In contrast, for dry or arid climates, you may not need a product that is as moisture-resistant.

If you’re in a region with high temperatures or intense sunlight, synthetic felt may be a better option due to its superior UV resistance. Asphalt felt, while reliable, tends to break down faster under prolonged exposure to sunlight, which could reduce the lifespan of your roof.

2. Roof Pitch and Type of Roofing Material

The pitch or slope of your roof can influence the type of felt you should choose. Steep-pitched roofs tend to shed water more efficiently, while flat or low-slope roofs require more durable and water-resistant materials to ensure that moisture does not seep under the roofing material. Synthetic felt is often a better choice for low-slope or flat roofs due to its stronger water resistance and durability.

The type of roofing material you plan to use also affects the choice of felt. For example, if you are installing asphalt shingles, a 15-pound asphalt felt may suffice as an underlayment. However, heavier materials such as slate or tile may require a thicker, 30-pound felt to provide additional protection.

3. Budget and Longevity

When purchasing felt, it’s important to balance cost with durability. While synthetic felt may have a higher initial cost, its durability, UV resistance, and longer lifespan can save you money in the long run by reducing the need for repairs or replacements. On the other hand, asphalt felt is more affordable upfront, making it a good option if you’re working within a strict budget.

If your primary concern is long-term performance and durability, synthetic felt is often the better investment, even though it may come at a higher cost. Asphalt felt, while cost-effective, may need to be replaced sooner due to its tendency to degrade over time, especially under extreme weather conditions.

4. Ease of Installation

Roofing felt is relatively easy to install, but synthetic felt is generally considered to be easier to work with. Its lighter weight and increased flexibility make it more manageable, especially for DIY roofing projects. Asphalt felt, on the other hand, can be heavier and more cumbersome to handle, particularly in larger rolls.

Synthetic felt often comes with features that make installation easier, such as adhesive backing or slip-resistant surfaces. However, both types of felt can be installed by professionals or experienced DIYers with the proper tools.

5. Environmental Impact

If sustainability is important to you, synthetic roofing felt may be a better choice due to its longer lifespan and recyclability. Some synthetic felt materials are made from recycled plastic or other eco-friendly components. Additionally, synthetic felt typically requires fewer resources to manufacture than traditional asphalt felt, making it a more environmentally friendly option.

Asphalt felt, while widely used, may not be as eco-friendly due to the production of bitumen and its reliance on petroleum-based products. However, it is still recyclable in some cases, though its overall environmental impact may be greater than synthetic alternatives.

Where to Buy Felt for Your Roof

You can purchase roofing felt from a variety of sources, including home improvement stores, online retailers, and specialty roofing suppliers. When purchasing roofing felt, make sure to choose a reputable vendor that offers high-quality materials. Some stores may also offer bulk purchasing options, which can save you money if you’re buying for a large roofing project.

Before making your purchase, be sure to compare prices and check for any promotions or discounts that may be available. If you’re working with a professional roofing contractor, they may have preferred suppliers or materials that they recommend based on the specific needs of your roof.

Buying felt for your roof is an essential step in ensuring that your roof provides maximum protection against the elements. Whether you choose traditional asphalt felt or modern synthetic felt, understanding the differences between these materials, as well as considering factors like climate, roofing material, and budget, will help you make the best decision for your home. Proper installation of high-quality roof felt not only extends the lifespan of your roof but also enhances its performance, keeping your home safe, dry, and energy-efficient.

Take the time to research the various options available, consult with roofing professionals if necessary, and make sure you choose the right roofing felt that fits your needs. Your roof is a critical part of your home, and investing in the right felt will ensure it continues to protect your home for years to come.

FAQ: Buying Felt for Your Roof

1. What is roof felt and why is it necessary?

Roof felt, also known as roofing felt or underlayment, is a protective layer installed under the shingles or roofing material. It serves as a moisture barrier, preventing water from seeping into the roofing structure, protecting the decking, and enhancing the roof’s durability.

2. What are the different types of roofing felt?

The two main types of roofing felt are asphalt felt and synthetic felt. Asphalt felt is made from organic or fiberglass matting soaked in asphalt, while synthetic felt is made from advanced materials like polyester or polypropylene, offering better strength, UV resistance, and durability.

3. What is the difference between 15-pound and 30-pound roofing felt?

The number (e.g., 15-pound or 30-pound) refers to the weight of a 100-square-foot roll of felt. 15-pound felt is lighter, often used in dry climates or as an underlayment for shingles, while 30-pound felt is thicker and provides better water resistance, ideal for areas with high moisture or wind exposure.

4. Can I install roofing felt myself, or do I need a professional?

Roofing felt can be installed by both DIYers and professionals. However, it’s important to ensure the proper application, such as overlapping seams, securing edges, and avoiding wrinkles. If you’re unsure, it’s best to hire a professional to ensure proper installation.

5. Is synthetic felt better than asphalt felt?

Synthetic felt is generally more durable and resistant to UV rays and tearing. It also has better water resistance and lasts longer than asphalt felt. While synthetic felt tends to be more expensive upfront, it may offer better long-term value due to its durability.

6. How long does roofing felt last?

The lifespan of roofing felt depends on the material used and weather conditions. Asphalt felt typically lasts around 10-20 years, while synthetic felt can last 25 years or more due to its higher durability and UV resistance.

7. Do I need to replace the felt if I’m replacing my roof shingles?

Yes, it’s highly recommended to replace the roofing felt when replacing shingles, as it acts as the foundation for your new roof. Old felt may have deteriorated over time, and using new felt ensures maximum protection and efficiency.

8. Can roofing felt be used on all types of roofs?

Roofing felt can be used on most types of roofs, including pitched, sloped, or flat roofs. The material choice may vary based on the roof’s slope, the climate, and the roofing materials used, but both asphalt and synthetic felts are versatile.

9. How do I choose the right roofing felt for my roof?

To choose the right roofing felt, consider factors like climate, roof slope, and the type of roofing material. For example, in wet climates, synthetic felt or 30-pound asphalt felt may be a better choice due to superior water resistance, while in drier regions, 15-pound asphalt felt may suffice.

10. How is roofing felt installed on a roof?

Roofing felt is typically installed in overlapping rows, starting at the eaves and working upward. The felt should be rolled out horizontally, and each row should overlap the one below it to ensure a watertight seal. The felt is nailed or stapled in place, with extra attention paid to seams and edges.

11. Does roofing felt contribute to energy efficiency?

Yes, roofing felt can help with energy efficiency by adding an extra layer of insulation. Synthetic felt, in particular, has higher breathability, which can help regulate attic temperatures and reduce the heat entering your home, contributing to energy savings.

12. How much roofing felt do I need for my roof?

To calculate the amount of roofing felt, measure the square footage of your roof and consider the size of the rolls you’re purchasing. Roofing felt usually comes in 36-inch wide rolls. Be sure to order a little extra to account for overlaps, cuts, and waste.

13. Is roofing felt waterproof?

Roofing felt is water-resistant, not entirely waterproof. It helps prevent water from reaching the decking if the roof covering fails, but it is not intended to act as a primary water barrier. Roofing materials like shingles or tiles provide the primary waterproofing layer.

14. Can roofing felt be used in combination with other underlayment materials?

Yes, roofing felt can be used in conjunction with other underlayment materials. For example, synthetic felt may be layered over asphalt felt for additional protection, or both can be used alongside a moisture barrier for enhanced water resistance, especially in high-risk areas.

15. How do I store roofing felt before installation?

Roofing felt should be stored in a dry, cool place, preferably indoors or under a tarp. Avoid exposing it to direct sunlight or heavy moisture, as these conditions can cause the felt to degrade before installation. Always check for any damage before use.