Roofing Underlayment: Types, Benefits, and Installation in Virginia

Roofing underlayment is a crucial component of any roofing system. It provides a barrier between the roofing material and the roof deck, protecting the structure from water damage and improving energy efficiency. 

If you’re planning to install a new roof in Virginia, it’s important to understand the different types of underlayment available and their benefits.

What is roofing underlayment?

This is a layer of material that is installed directly onto the roof deck before the roofing material is applied. It serves as a secondary layer of protection against water infiltration and helps to regulate temperature and humidity levels within the attic space.

Types of roofing underlayment

There are several types, but here are the three main types: felt, synthetic, and rubberized asphalt.

#1: Felt underlayment

Felt underlayment is the popular, traditional choice. It is made of organic materials, such as wood or paper fibers, which are saturated with asphalt to make them water-resistant. Felt underlayment is available in different weights and thicknesses, and it is typically less expensive than synthetic or rubberized asphalt underlayment.

#2: Synthetic underlayment

Synthetic underlayment is made of polymer materials, such as polypropylene or polyester, which are designed to be more durable and resistant to tearing than felt underlayment. Synthetic underlayment is also lighter than felt, making it easier to install, and it has a longer lifespan than felt underlayment.

#3: Rubberized asphalt underlayment

Rubberized asphalt underlayment is a mixture of rubber polymers and asphalt. It is the most expensive kind of underlayment, but it provides the highest level of protection against water infiltration and wind-driven rain. Rubberized asphalt underlayment is also the most durable underlayment type, with a lifespan of up to 50 years.

Benefits of roofing underlayment

Installing this provides several benefits, including:

#1: Waterproofing

This underlayment acts as a secondary layer of protection against water infiltration. Even if shingles or other roofing materials become damaged or torn off, the underlayment will help prevent water from seeping into the roof deck and causing damage to the structure.

#2: Temperature regulation

It will help to regulate temperature and humidity levels within the attic space. This can help to reduce energy costs and prevent moisture buildup, which can lead to mold growth and other problems.

#3: Protection from wind-driven rain

This will provide a barrier against wind-driven rain, which can be especially important in areas like Virginia that are prone to severe weather conditions.

#4: Protects against ice dams

In colder climates, ice dams can form on roofs and cause water to back up under the shingles, leading to leaks and damage. Installing the underlayment can help to prevent ice dams from forming and protect against this type of damage.

#5: Increases energy efficiency

Certain types of underlayment, such as reflective underlayment, can help to regulate the temperature of your attic space and improve the energy efficiency of your home.

#6: Reduces noise

This will be able to help reduce noise from rain or hail hitting the roof, making your home more comfortable and peaceful.

#7: Adds an extra layer of protection during roof repair

If you need professionals to make repairs to your roof look to Mighty Dog Roofing Richmond in Virginia, they can advise and provide the underlayment that will provide an extra layer of protection while the shingles are removed and replaced.

#8: Increases home value

Installing high-quality underlayment can increase the overall value of your home and make it more attractive to potential buyers if you decide to sell in the future.

Installation of roofing underlayment

Proper installation is crucial for ensuring its effectiveness in protecting the roof structure. Here are the steps involved in the roofing installation: 

#1: Preparation

Before installing the underlayment, ensure that the roof deck is clean and free of debris. Remove any old roofing materials or damaged underlayment. Check for any protrusions or irregularities that may require additional attention or special care during installation.

#2: Placement

Start at the lowest point of the roof and work your way up, ensuring that the underlayment is placed in a shingle-like pattern. Overlap the edges of each underlayment strip by at least 2 inches to create a water-resistant barrier.

#3: Fastening

Fasten the underlayment to the roof deck using roofing nails or staples, spacing them according to the manufacturer’s instructions. Be careful not to overdrive the fasteners, as this can damage the underlayment and compromise its effectiveness.

#4: Overlapping

Ensure that each strip of underlayment overlaps the previous one and that the seams are sealed with roofing cement. This will help to prevent water infiltration through the gaps between the underlayment strips.

Choosing the right roofing underlayment for your Virginia home

When choosing one for your home in Virginia, consider factors such as the climate, the slope of your roof, and your budget. Synthetic or rubberized asphalt underlayment may be a better choice if your roof has a steep slope or if you live in an area with severe weather conditions. Felt underlayment may be a more cost-effective option if you have a lower-sloped roof and live in a less severe climate.


Roofing underlayment is a critical component of any roofing system, providing an additional layer of protection against water infiltration, regulating temperature and humidity, and protecting against wind-driven rain. 

By understanding the different types of underlayment available and their benefits, you can choose the best option for your Virginia home and ensure proper installation for maximum effectiveness.

Frequently Asked Questions (FAQs) 

What is the lifespan of roofing underlayment?

The lifespan totally depends on the type of material used and the environmental conditions. Felt underlayment typically has a lifespan of 15-30 years, while synthetic and rubberized asphalt underlayment can last up to 50 years.

Can roofing underlayment be used alone without shingles?

The underlayment on the roofing is designed to be used as a secondary layer of protection and should not be used alone without shingles or other roofing materials.

How much does roofing underlayment cost?

The cost of installation typically varies depending on the type of material used and the size of the roof. Felt underlayment is typically the least expensive option, while synthetic and rubberized asphalt underlayment can be more expensive.

Can roofing underlayment be reused?

This should not be reused once it has been removed from the roof, as it may have been damaged or compromised during the removal process.

Do I need a permit to install roofing underlayment?

In Virginia, a building permit is required for any roofing work that involves the replacement or repair of more than 25% of the total roof area. This includes the installation of said underlayment. Be sure to check with your local building department to ensure that you comply with all necessary regulations and requirements.

Can I install the roofing underlayment myself? 

While it is possible to install roofing underlayment yourself, it is generally recommended to hire a professional roofing contractor to do the job. Improper installation can lead to leaks and other issues, so it is important to ensure that the underlayment is installed correctly for maximum effectiveness and protection.

Do I need to install roofing underlayment? 

While it is not legally required in all areas, the installation is highly recommended by professionals to protect against leaks, improve energy efficiency, and prolong the life of your roof.


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