What Is Spray Foam Roof Insulation? A Simple Guide

Spray foam roof insulation, often referred to as spray polyurethane foam (SPF) roof insulation, is an innovative way to protect your roof. Many property owners wonder whether spray foam insulation is a good option for their roofs. The short answer is spray foam roofing insulation works really well with both sloped and flat roofs. 

At BRH Enterprises LLC, we are committed to providing professional roofing services to Mayville and the surrounding areas of Wisconsin. So, if you are struggling to find the right roofing materials for your property, our professionals are here to help. Just give us a call at (920) 249-4228. 

In this article, we will be covering all about spray foam roof insulation. Let’s get started.

What Is Spray Foam Insulation?

Spray foam insulation is a popular insulation method where liquid polyurethane foam is sprayed onto surfaces like walls, ceilings, and attics. Once applied, the liquid foam expands and solidifies, creating a thick and flawless layer of insulation.

This insulation type acts as both an air sealant and a thermal barrier, preventing heat transfer and air leaks. Since the 1980s, spray foam insulation has been popular for commercial, residential, and industrial buildings because of its effectiveness and durability.

When installed correctly, spray foam insulation can last for decades, often up to 80 years, with minimal maintenance. Its long lifespan, coupled with its energy-saving properties, makes it a valuable investment for property owners.

You might also like: Does Spray Insulation Remove The Need For Roof Ventilation?

What Are The Pros Of Spray Foam Roof Insulation?

There are several reasons why spray foam insulation has become a popular choice among homeowners. Here, we will take a closer look at its advantages:

#1 Superior Energy Efficiency

One of the most noteworthy benefits of spray foam insulation is its high R-value (thermal resistance) compared to other types of insulation materials. The higher the R-value, the better the material insulates your home.

Spray foam insulation offers an R-value of R-5 to R-7 per inch, which surpasses materials like extruded polystyrene (XPS) insulation (R-5 per inch) and traditional fiberglass batts (R-3 per inch). 

By reducing heat transfer more effectively, spray foam helps lower heating and cooling costs, often allowing energy savings to offset the initial investment.

#2 Airtight Seal

Spray foam insulation forms a smooth barrier that fills even the smallest gaps and cracks, eliminating air leaks. This feature ensures consistent indoor temperatures and reduces energy waste due to drafts or poor sealing, which is common with traditional insulation methods.

#3 Moisture Resistance

In addition to sealing the air leaks, spray foam insulation also blocks moisture from entering your home. Closed-cell spray foam is particularly effective at resisting water, which helps prevent issues like mold and mildew.

#4 Longevity and Durability

Unlike traditional insulation materials that sag or deteriorate over time, spray foam insulation maintains its structure and effectiveness for decades. This durability makes it a long-term solution for homeowners looking to reduce maintenance needs.

#5 Noise Reduction

The dense structure of spray foam also helps to soundproof homes by reducing noise transfer between rooms or from external sources.

#6 Eco-Friendly Features

While spray foam requires chemical components, it reduces overall waste by lasting longer and minimizing energy consumption. Most modern formulations have low volatile organic compounds (VOCs) and no ozone-depleting potential (ODP).

What Are The Cons Of Spray Foam Roof Insulation?

While spray foam insulation offers many advantages, it’s important to consider its potential downsides:

#1 UV Sensitivity (When Exposed)

Spray foam insulation is not naturally UV-resistant. However, this is more relevant in roofing applications. Attic insulation does not receive any direct sunlight, so this is not a major problem to consider. 

#2 Installation Depends on Weather

Applying spray foam insulation requires specific environmental conditions. For optimal results, the temperature should be above 50 degrees with low humidity. Poor weather conditions may delay installation, especially in unconditioned spaces.

#3 Potential Overspray

If the foam isn’t applied carefully, it can spread to unintended areas, causing damage or requiring cleanup. Professional contractors mitigate this risk by using protective measures.

#4 Requires Skilled Installation

Proper installation of spray foam insulation requires experience and precision. Mistakes can result in underperformance, so hiring a certified contractor is essential for quality results.

How Much Does Spray Foam Insulation Cost?

The cost of spray foam roof insulation depends on the type (open-cell or closed-cell), the area to be covered, and the thickness required. On average, homeowners can expect to pay:

👉 Open-cell spray foam: $0.44 to $0.65 per board foot

👉 Closed-cell spray foam: $1.00 to $2.50 per board foot

For an attic or crawl space, this translates to a total cost ranging from $1.50 to $4.50 per square foot, depending on the insulation’s thickness and the complexity of the project.

How To Install Spray Foam Insulation In Your Attic?

It is not recommended to attempt to install spray foam insulation in your attic without prior experience. Knowing the steps involved in the installation process can help you ensure the work is being done accurately. 

Here are the general steps involved in installing spray foam attic insulation:

👉 Step: 1 Preparation

Clear the attic space by removing any existing insulation and sealing gaps to prevent air leaks. This step is very important for improving the effectiveness of the spray foam roof insulation.

👉 Step: 2 Conduct an Energy Audit

Assess the insulation needs of your attic to determine the appropriate thickness of the required spray foam insulation.

👉 Step: 3 Select the Right Product

Choose between open-cell and closed-cell spray foam insulation, with closed-cell being preferred for its superior air sealing and moisture resistance though it is more expensive.

👉 Step: 4 Application

In the fourth step, a spray foam gun is used to apply the SPF roof insulation evenly across the rafters or trusses. Start from the furthest point from the access and work your way back, applying in layers to allow for expansion.

👉 Step: 5 Curing

The final step is allowing the spray foam insulation roofing to cure as per the manufacturer’s instructions, creating a protective and effective barrier against heat loss and improving the energy efficiency in your home.

How To Choose Between Open-Cell And Closed-Cell Insulation?

To make a final choice between open-call and closed-cell spray foam insulation, you will need to consider a few things. Below, we will quickly look at these important factors. 

#1 R-Value

The very first thing to look for is how much R-value per inch of insulation your attic space needs. 

Closed-cell spray foam has a higher R-value, ranging from R-6 to R-8 per inch, which makes it a good choice if you live in snowy regions. 

On the other hand, open-cell foam averages around R-3.6 per inch, and it is commonly used in areas with moderate temperatures.

#2 Moisture Resistance

Closed-cell foam is dense and moisture-resistant, which makes it suitable for areas like Wisconsin that often receive heavy rain. 

In contrast, open-cell foam is more absorbent and can allow moisture to pass through, which may lead to mold issues if used in damp conditions.

#3 Cost

Open-cell spray foam is generally less expensive to install due to its lower material costs and faster application process. 

However, achieving the same R-value with open-cell requires more thickness, potentially increasing overall costs in the long run.

#4 Application Area 

Closed-cell foam is used for exterior applications or areas exposed to weather, while open-cell foam is better for interior insulation and soundproofing.

Remember that your choice should align with your insulation goals, budget, and specific environmental conditions. If you are still confused about how to choose the right insulation type for your roof in Wisconsin, our experts are here to help. 

Also Read: The Ultimate Guide To Types Of Attic Insulation

Schedule Your Free Roof Inspection In Wisconsin Today

If you are concerned about the condition of your roof, we offer free roof inspections in Mayville and the surrounding areas of Wisconsin.

At BRH Enterprises LLC, we are your trusted roofers. From minor repairs to full roof replacements, we provide reliable, professional roofing services to both home and business owners. To get a custom roof quote or to schedule your free roof inspection, call us today at (920) 249-4228.