Exploring The Different Roof Underlayment Types

Roof underlayment might not be the first thing that comes to mind when you think about your home’s roof, but it plays a crucial role in its integrity and longevity. But what is it, and how do you know when it is time to replace it?

In this blog, we’ll explain:

• What roof underlayment is
• Why it’s important
• The various roof underlayment types available
• When to replace it
• How much it costs

What is Roof Underlayment?

Roof underlayment is a protective layer installed between the roof deck and the roofing material (shingles, tiles, metal panels, etc.). It serves as an added barrier against moisture infiltration, providing extra protection to the roof structure and the interior of the building.

Importance of Roof Underlayment:

• Moisture Protection: Roof underlayment acts as a secondary barrier against water intrusion, preventing leaks and moisture damage to the roof deck and underlying structure.
• Temperature Regulation: It helps to regulate temperatures within the attic space, reducing heat transfer in summer and heat loss in winter, thus improving energy efficiency.
• Wind Resistance: Roof underlayment enhances the roof’s resistance to wind uplift, especially in areas prone to high winds or storms.
• Added Protection: In case of damage to the primary roofing material (shingles, tiles, etc.), the underlayment provides temporary protection until repairs can be made, preventing further damage to the interior.

Different Types of Roof Underlayment

Trying to decide which style of roof underlayment is right for you? Here is our quick guide to the pros and cons of various types.

1) Asphalt-Saturated Felt:

Made from organic or fiberglass materials saturated with asphalt. It is available in various thicknesses and weights.

• Pros: Affordable, provides good temporary protection, widely used and accepted.
• Cons: Susceptible to tearing during installation, can degrade over time due to UV exposure, not as resistant to moisture as newer alternatives.

2) Synthetic Underlayment:

Made from polyethylene or polypropylene materials. It is lightweight and highly resistant to tears and wrinkles.

• Pros: Superior tear resistance, UV resistant, offers better waterproofing compared to felt, easier to install.
• Cons: Generally more expensive than felt, may not be as widely accepted in all regions.

3) Rubberized Asphalt Underlayment:

This style of underlaymen consists of asphalt coated with a layer of rubberized polymer. It provides excellent waterproofing and flexibility.

• Pros: Superior waterproofing properties, highly durable, remains flexible in cold temperatures, self-sealing around fasteners.
• Cons: Higher cost compared to traditional felt underlayment, may not be necessary for all roofing applications.

4) Non-Bitumen Synthetic Underlayment:

This material is made from materials such as polyethylene, polypropylene, or polyester. It offers high tensile strength and excellent durability.

• Pros: Lightweight, tear-resistant, UV resistant, can be left exposed for longer periods during roof installation.
• Cons: Higher initial cost, may not be as widely available as other types of underlayment.

When to Replace Your Roof Underlayment

Knowing when to replace your roof underlayment is essential for maintaining the integrity of your roof system. Here are some signs that indicate it’s time for replacement:

• Visible signs of damage or deterioration, such as tears, wrinkles, or curling edges.
• Water stains or leaks in the attic or ceilings.
• Roofing material reaching the end of its lifespan (typically 15-30 years for asphalt shingles).
• Planning to replace the primary roofing material, as it’s recommended to replace the underlayment at the same time for optimal protection.

How Much Does Roof Underlayment Cost?

The cost of roof underlayment varies depending on the type of material, quality, brand, and the size of your roof. Here’s a general overview of the costs:

• Asphalt-Saturated Felt: $0.10 – $0.50 per square foot
• Synthetic Underlayment: $0.20 – $0.80 per square foot
• Rubberized Asphalt Underlayment: $0.40 – $1.00 per square foot
• Non-Bitumen Synthetic Underlayment: $0.30 – $1.00 per square foot

It’s important to note that while synthetic and rubberized underlayments may have a higher upfront cost, they often provide better long-term protection and durability, potentially saving you money on future repairs.

Learn More About Types of Roofing Underlayment

Roof underlayment is a crucial component of any roofing system, providing essential protection against moisture, wind, and other elements. Understanding the different types of underlayment available, their pros and cons, and knowing when to replace them can help homeowners make informed decisions to safeguard their investment and prolong the lifespan of their roof. While the initial cost of quality underlayment may be higher, the long-term benefits in terms of durability and protection make it a worthwhile investment for any roofing project.

Contact Roof Medic today to learn about roof underlayment types and schedule you roof replacement.