What Is R-Value?: Crawl Space Insulation Ratings

When purchasing a home, the foundation type might not be a primary concern. Yet, different foundations can lead to unique issues. For example, a house with an open crawl space can be colder in winter compared to one on a concrete slab, leading to higher heating costs.

Additionally, open crawl spaces are susceptible to mold and mildew growth. Therefore, it’s crucial to insulate these areas effectively. This is where the ‘R-value’ comes in. Higher R-value insulation materials are recommended for their superior thermal resistance. If you’re looking to understand this concept better or need advice on insulating under-covered areas, you’re in the right place.

What Is R-Value? 

The R-value is a measure used to tell you how well certain insulation can keep the heat from leaving or entering your home, which is important for preventing heat loss. The higher the R-value, the better the insulation. The R-value depends on several factors, such as the density, thickness, and type of insulation. 

Crawl Space Insulation Types 

Different insulation materials have different R-values. When you have decided that you want to insulate your crawl space, you need to consider the material’s R-value before you find the right one for your crawl space. Here is a list of materials that are often used as insulation: 

• Roll: This insulation type is made of glass fibers and it is commonly used to insulate large, open spaces such as the area over attic joists. It comes in wide sheets. 
• Batting: This fiberglass insulation comes in the form of bats and is used for covering walls, attics, and areas between joists. When it is compressed, this insulation has a lower R-value. 
• Blown-in: The blown-in type of insulation consists of fiberglass or loose cellulose. It can be used on attics and walls that have never been insulated before. The best thing about this type of insulation is that it can get into all kinds of nooks and crannies. 
• Spray foam: Since it is made of expanding polyurethane foam, spray foam enlarges once it is sprayed, which makes it convenient for insulating pipes and wires. Usually, spray foam has an R-value of 6.3 and low-density. 
• Rigid foam: Made from expanded or extruded polystyrene, the rigid foam has a smoother surface and great thermal properties. Some have an R-value between 3.6 and 4, but can have a value above 10, and is used to insulate the crawl space or basement. 

What’s the Best Insulation Product? 

To be an excellent insulation product, a material needs to be fire-resistant, compact, and effective in slowing down heat transfer. It should also help keep the structure safe from pests and mold growth. If you wish to insulate your crawl space, check out the local codes and R-value requirements in your area. You can also consult with expert contractors in Michigan who will recommend the best insulation products for your home. A highly praised product is FSM’s rigid foam insulation panels that have an R-value of 15. 

Identifying and Covering Under-Insulated Areas 

There are many areas in your home that might be under-insulated or uninsulated completely. Locating and properly insulating those spaces can help you keep the cold air out of your home, which will instantly reflect on your bills. With quality insulation, you can save more and ensure a comfortable indoor environment. Here are some of the areas in your home you should check up on: 

• Crawl space: If you have a vented crawl space, you should inspect the perimeter walls. Otherwise, you should check out the space between the floor joists. You should avoid using soft materials since they can easily soak up the moisture and turn your crawl space into a comfortable environment for mold growth and pests. FSM’s insulation panels are a great solution for crawl space insulation. 
• Attic: If you have an insulated attic, go up there and stick a tape measure into the insulation. It needs to be at least 19 inches deep. If it is thinner, your attic is under-insulated, so you might want to consider adding another layer of insulation to the existing one. 
• Basement: If you have an unfinished basement, inspect the walls and rim joists. 
• Knee walls: Knee walls are located between your living area and the garage or the attic. If your home was built three decades ago or even earlier, it most likely doesn’t have effective insulation. Contact professional contractors in Michigan and have them apply blow-in insulation to reduce heat loss. 
• Floors: You will make your living space much more comfortable if you insulate the floors above unheated basements. You can use mineral wool batts on the subfloor. 

Why Insulate Your Home? 

There are so many reasons why you should insulate your home. Here are just some of them: 

• Lower utility costs: When you insulate your home, it stays cooler in the summer and warmer in the winter, so your heating and cooling appliances don’t have to run as long, which lowers utility costs. 
• Noise reduction: Traffic noise can keep you up at night and make it harder to focus during the day. With proper insulation, you can soundproof your place and make your home quieter. 
• Enhance energy efficiency: With insulation on exterior walls, you will prevent heat from leaking into unheated areas through openings and fixtures like door and window frames and the entry/exit points of pipes and wires. 
• Moisture control: Insulation creates a barrier against moisture that is a result of everyday activities such as bathing or washing. 

If you want to insulate your crawl space or basement with materials that have a high R-value, contact professionals at FSM to schedule a free inspection and estimate. 

Leah Leitow

Content Writer

Leah is a Content Writer for Groundworks with nearly ten years of experience working in the foundation repair industry. Her experience ranges from working with homeowners to find the right solution to training inspectors and staff. In her background as a Michigan journalist, she gained invaluable insight into people's lives throughout our state. Leah lives in metro Detroit with her husband and two sons.

Related Resources

How to Install Crawl Space Insulation in 6 Steps

Tips for Maintaining Your Crawl Space Encapsulation System

The Crawl Space Argument: Vented vs. Encapsulated