Roofing paper

Types of roofing paper

Roofing paper, also known as felt paper or roofing felt, is a material used in roofing systems to provide an additional layer of protection against moisture. It is typically installed between the roof deck and the shingles or other roofing materials. Roofing paper acts as a barrier, preventing water from seeping into the roof deck and protecting it from potential damage caused by moisture, and is available in various types such as:

• Asphalt-Saturated Roofing Paper:

  This type of roofing paper is the most commonly used for residential roofing projects. It features a base layer of felt paper, which is typically polyester or fiberglass, that is saturated with asphalt. The saturation process makes it waterproof and more durable. There are two main varieties: regular and heavy-duty asphalt-saturated roofing paper. The former is used for asphalt shingle roofs, while the latter is designed for more demanding applications like roofs with larger water.

• Non-Asphalt-Saturated Roofing Paper:

  This type of roofing paper is less commonly used than asphalt-saturated roofing paper. It is typically made from natural fibers such as cellulose or paper. It is treated with a waterproofing chemical to make it water-resistant. There are two main types of non-asphalt-saturated roofing paper: organic and synthetic roofing paper. The former is lighter and easier to work with but less durable than asphalt-saturated paper. The latter is made from polypropylene or other synthetic materials and is known for its durability and resistance to tearing and UV rays.

• Rubberized Asphalt Roofing Paper:

  This roofing paper is designed for low-slope or flat roofs. It features a rubberized asphalt compound that is both waterproof and elastic. This allows it to expand and contract with temperature changes without cracking. It is ideal for areas prone to heavy rain or snow and is commonly used in the construction of torch-down or rolled roofing systems.

• Ventilated Roofing Paper:

  Ventilated roofing paper is a specialized type of underlayment designed for pitched roofs. It is equipped with a breathable membrane that allows moisture vapor to escape from the roof structure while preventing water from penetrating. This helps to prevent the buildup of condensation and mold growth in the roof space. Ventilated roofing paper is typically made from synthetic materials and has a textured surface to facilitate water runoff.

Functions and features of roofing paper

Roofing paper helps waterproof the roof deck by creating a barrier that prevents water from seeping through. It is commonly used in roof construction. Here are some key functions and features of roofing paper.

• Moisture Barrier

  The primary function of roofing paper is to act as a moisture barrier. This prevents water from penetrating the roof deck. Water is a significant cause of roof decay and damage. The roofing paper helps to extend the lifespan of the roof by preventing it from being damaged by water.

• Wind Drive Resistance

  Wind-driven rain can force water through roof deck seams and gaps. Roofing paper helps to resist this by creating a continuous barrier. It prevents water from being driven into the roof deck by wind.

• Protection from Debris

  During the installation of the roof, debris such as nails, and sharp objects can damage the roof deck. Roofing paper provides a protective layer that prevents debris from penetrating the roof deck. This helps to prevent punctures and cuts on the roof deck.

• Temperature Regulation

  Some types of roofing paper have reflective coatings. They help to regulate the temperature of the building. This is because they reflect sunlight. Reflecting sunlight helps to keep the building cool. A regulated temperature reduces the workload of cooling systems. This saves energy and reduces cooling costs.

• Fire Resistance

  Some types of roofing paper have fire-resistant properties. These papers include Type III and Type IV roofing papers. They help to prevent the spread of fire. This protects the building and increases the safety of occupants.

• Durability

  Roofing paper is made from materials such as asphalt, fiberglass, and felt. These materials are resistant to tearing, and punctures. Roofing paper is designed to withstand harsh environmental conditions such as extreme temperatures and UV radiation. This ensures that it provides long-term protection to the roof.

Scenarios of roofing paper

There are different applications and scenarios of roofing paper, including:

• Residential and commercial construction: Roofing felt is used in residential and commercial construction as an underlayment. It is placed between the roof deck and the shingles or other roofing materials. Roofing paper acts as a moisture barrier, protecting the roof deck from water and extending the life of the roof. Roofing paper is also used as a vapor barrier in residential and commercial buildings. It is installed under the roof or in the walls to prevent moisture from moving. This helps to reduce the risk of mold and improves the energy efficiency of the building.
• Climate and environmental conditions: Different types of roofing paper are designed for specific climatic and environmental conditions. For example, asphalt-saturated felt paper is commonly used in temperate climates. It offers good protection against rain and snow. However, it is not suitable for extremely hot or cold temperatures. On the other hand, polyethylene roofing underlayment is preferred in hot climates. It reflects UV rays and prevents heat buildup in the roof. In addition, it is ideal for cold climates because it remains flexible.
• Roofing material types: Different roofing papers are used depending on the type of roofing material used. For example, felt paper is used with asphalt shingles. It provides an additional moisture barrier. Synthetic underlayment is suitable for tile and metal roofing. It offers better puncture resistance and tear strength.
• Specialized applications: Roofing paper is used for specific applications in roofing. For example, it can be placed on the roof valleys, around chimneys, and skylights to prevent water from penetrating. This creates a water-tight barrier in vulnerable areas. It can also be used as a temporary roofing solution during construction. It protects the building from water damage until the final roofing is installed.

How to choose roofing paper

When selecting the ideal roofing paper for a specific project, consider the following factors:

• Type of roofing

  The type of roofing system significantly influences the choice of roofing paper. Different roofing materials and designs may necessitate specific underlayment types. For instance, asphalt shingles often work well with fiberglass or asphalt felt underlayment, while tile or metal roofs may require synthetic underlayment for added durability and moisture resistance. Additionally, the roofing design, such as steep or flat slopes, may impact the performance of underlayment and, thus, should be considered when selecting roofing paper.

• Climate and weather conditions

  The local climate and weather conditions play a crucial role in determining the most suitable roofing paper. Areas with high humidity or heavy rainfall require underlayment with superior moisture resistance, such as synthetic roofing paper, to prevent mold growth and leaks. In contrast, regions with extreme heat may benefit from reflective underlayment to reduce attic temperatures and prolong roof lifespan. Similarly, windy areas may necessitate more durable underlayment to prevent tearing, while cold climates may require vapor barriers to reduce condensation.

• Budget and cost

  Budget and cost considerations are essential when selecting roofing paper, as various types and brands come with different price points. While premium underlayment may have a higher upfront cost, it could offer better durability and protection, potentially saving money on future repairs. Therefore, it is essential to find a balance between cost and quality to ensure the chosen roofing paper meets the roofing requirements without exceeding the allocated budget.

• Installation

  The ease of installation and compatibility should also be considered when choosing roofing paper. Some underlayment types, like synthetic roofing felt, are lightweight and easy to install, making them a good choice for DIY projects or cost-sensitive applications. On the other hand, traditional asphalt felt, while heavier, may be preferred by professional roofers due to its proven performance. Additionally, compatibility with the roofing material is crucial to ensure a seamless and efficient installation process.

Roofing Paper Q&A

Q1: What is roofing paper used for?

A1: Roofing paper is used as a moisture barrier between the roof deck and shingles. It protects against water, debris, and extreme temperatures, prolonging the life of the roof.

Q2: What are the two types of roofing felt?

A2: The two types of roofing felt are asphalt-saturated organic felt and fiberglass/synthetic felt. The former uses paper base layers, while the latter uses fiberglass/synthetic base layers.

Q3: Which roofing paper is better?

A3: Fiberglass roofing paper is better because it is lighter, more durable, and provides waterproof protection. It is preferred for modern roofing applications.

Q4: How thick is roofing paper?

A4: Roofing paper is usually 0.03 inches thick. However, it may vary slightly depending on the type and manufacturer.

Q5: What is the difference between tar paper and roofing paper?

A5: Tar paper is a type of roofing paper that uses asphalt coating for waterproofing. It is heavier and used for low-slope roofs. Roofing paper also includes felt paper and other synthetic materials.