Spray Foam Insulation for Crawl Spaces : A DIY Guide

Uninsulated crawl spaces are uncomfortable and highly energy inefficient regardless of whether they are vented or not. Crawl space insulation is one of the secrets to reducing your energy bills and making your home comfortable all year round.

DIY Crawl Space Insulation with PU Spray Foam

In this article, we will guide you through the process of insulating your crawl space with spray foam with a step-by-step DIY guide. We will also discuss the benefits of spray foam and the cost of crawl space insulation.

Why Insulating Your Crawl Space is Essential?

Many homeowners neglect their crawl spaces, but it is an important part of the house. Insulation is important because allergens and pests can get into the living area through crawl spaces. Naturally, a crawl space is an open space for ventilation; without proper insulation, it can cause heat loss in your home.

Crawl space insulation reduces mold infestation by preventing moisture buildup. Insulation improves the air quality in your home by keeping the crawl space sealed from allergens. Insulating crawl spaces allow you to maintain a stable temperature all year in your home, even during extreme weather conditions.

What are the Benefits of Crawl Space Insulation?

Benefits of Crawl Space Insulation

Crawl space insulation is essential to make your home comfortable during winter or summer. The benefits of crawl space insulation include the following:

Reduces Heating and Cooling Bill

Energy bills are high because the HVAC system consumes a lot of energy to keep your home warm. Crawl space insulation can save up to 15% of energy bills by reducing the heat transfer between the living area and crawl space.

Crawl space insulation will reduce the amount of energy consumed for heating and cooling in your home. In other words, less energy would be required to keep your home warm during harsh weather conditions

Prevents Moisture, Mold & Pest

Mold growth is caused by moisture buildup, and it can be prevented by insulating crawl spaces to control moisture levels. The insulation in your crawl space can also prevent pests such as rodents and insects. 

Maintains Consistent Temperature

Crawl space insulation helps to maintain a consistent temperature in your home all seasons by preventing heat transfer in your crawl space. Heat is trapped in your home when your crawl space is insulated in winter.

Also, crawl space floor insulation prevents heat from entering your home during summer. Insulation will also improve the comfort and efficiency of your home by maintaining a consistent temperature. 

Increases Indoor Air Quality

Another significant benefit of crawl space insulation is that it increases the air quality in your home by making it air-sealed, preventing dust and unwanted air pollutants from entering.

Reduces Noise Pollution

Crawl space insulation helps to reduce noise pollution in your home by absorbing sound. Insulation acts as a sound barrier to reduce the sound transmitted into your living area.   

Increases Home Resale Value

Crawl space insulation increases the resale value of your home by making it energy efficient and comfortable. Every potential homeowner would prefer to buy a thermally insulated home that saves energy costs.

How to Choose the Right Insulation for Your Crawl Space?

Choosing the right insulation for your crawl space insulation is as important as the insulation process itself. Choosing the right insulation for your crawl space depends on significant factors like budget, climate, and individual preference. 

There are different types of crawl space insulation, like fiberglass, spray foam, batt insulation, etc, but how do you determine the right one to use? This section will highlight 3 common insulation types and their characteristics. 

Fiberglass Batts Insulation: 

Fiberglass batts insulation is a common type of insulation that is cheap and easy to install. Fiberglass is not ideal for crawl space insulation because it absorbs moisture. Moisture can lead to wood rot and mold growth.

Rigid Foam Insulation: 

Rigid foam board insulation provides a strong barrier that can be resistant to moisture infiltration and air infiltration in crawl spaces. Rigid foam insulation is difficult to install, and it is expensive when compared to fiberglass batts insulation. 

Spray Foam Insulation: 

Spray foam insulation is the best insulation for crawl spaces. It provides a tight, air-sealed barrier in crawl spaces to prevent air and moisture from entering your living area. Spray foam insulation is preferred over other insulation methods because it is durable, can be installed as a DIY project, and helps save energy costs. 

Spray Foam Insulation Worker

The Pros and Cons of Spray Foam Insulation for Crawl Spaces

Spray foam insulation is a popular type of insulation that is made up of two chemical products. As spray foam reacts, it produces foam that is used to seal air leaks, gaps, and holes in crawl spaces. 

Many homeowners use spray foam insulation for ceiling insulation, attic insulation, and basement insulation because of its numerous benefits. However, there are some drawbacks associated with using spray foam insulation for crawl spaces. 

Pros of Spray Foam for Crawl Space Insulation

The advantages of spray foam crawl space insulation include the following:

  • Provides uniform coverage around pipes, wires, ducts, and difficult-to-reach areas in your crawl space, like rim joists.
  • Offers a high R-value.
  • Prevents moisture buildup and can be used as a flood barrier.
  • Provides soundproof effects.
  • Durable and last longer than most insulation methods.

Cons of Spray Foam for Crawl Space Insulation

The disadvantages of spray foam crawl space insulation include the following:

  • Expensive to install.
  • It can lead to health problems if it is not properly installed.

Costs of Insulating a Crawl Space with Spray Foam Insulation Kit

The cost to spray foam crawl space depends on the type of spray foam insulation used and the area of the space to be installed. On average, crawl space insulation cost with spray foam insulation is $0.7 to $1.5 per square foot.

There are two different types of spray foam insulation: Open-cell spray foam insulation and closed-cell spray foam insulation. The cost of crawl space insulation with closed-cell spray ranges between $1 to $1.5 per square foot and costs between $0.55  to $0.70 for open-cell spray foam. The benefits and properties of both types of insulation can be found in this article Closed-cell vs Open-cell Insulation Foam

For example, it would cost between $1000 to $1500 to insulate a 1000square feet crawl space with closed-cell spray foam. For the same crawl space area, it would cost $550 to $750 to insulate with open-cell spray foam insulation.

Insulating Your Crawl Space: A Step-By-Step DIY Guide

The cost of getting a professional to insulate your crawl space with spray foam can be quite expensive. Nevertheless, you can reduce costs by installing your crawl space as a DIY project. To avoid complications after installation, spray foam insulation must be installed properly. 

Here is a step-by-step DIY guide on how to insulate your crawl space. 

Step-1: Prepare the Crawl Space

The first step is to clear your crawl space of debris, dirt, and unwanted items. This is necessary to make sure the crawl space is clean and dry. 

Step-2: Measure the Crawl Space 

After cleaning your crawl space, take a measurement of the area of your crawl space. This is done to know the amount of insulation kit needed for proper insulation. 

Step-3: Purchase a Spray Foam Insulation Kit 

Purchase a spray foam insulation kit such as Fast Coat Product and spray foam gun. Fast Coat Product is the best spray foam material with an excellent R-value of R5.66 per inch thickness. It is used for all types of home insulation, like attic insulation and wall insulation

Step-4: Set Up The Spray Foam Insulation Equipment

The next step is to set up for installation by getting the right equipment and protective gear needed. Put on protective gear like gloves, overalls, and goggles to cover your skin. Also, check the instruction manual on the spray foam kit on how to attach the spray gun and regulate pressure. 

Step-5: Apply the Spray Foam Insulation

After getting the necessary equipment and gear, apply the spray by starting from one end of your crawl space to another end. Applying spray foam to holes or gaps in your crawl space is important. 

Step-6: Allow the Insulation to Dry

After spraying, allow the foam to dry. Curing is the process of allowing the foam to dry and it should last at least 24 hours. 

Step-7: Apply a Second Coat (If Necessary)

It is important to check if the spray foam was not over-applied to some areas; you can trim with a knife to make the foam even. Also, check difficult-to-reach areas to be sure the foam was applied to every area. If not, reapply the foam a second time.

Step-8: Seal the Vents

Seal vents, outlets, and doors that lead to your crawl space. Hydraulic cement, vent covers, and sealed doors can be used to achieve this.

Step-9: Inspect the Crawl Space

After curing, inspect your crawl space regularly for any signs of drafts, mold, or moisture. 

Crawl Space Insulation: Frequently Asked Questions

Is Crawl Space Insulation Worth It?

Yes, crawl space insulation is important to make your home energy efficient and comfortable. As a result of crawl space insulation, you can also reduce your energy bills and preserve the air quality in your home.

What is R-Value Insulation For Crawl Space?

The recommended R-value for crawl space insulation is R9, according to the Department of Energy. Spray foam insulation has a high R-value, which means it resists heat transfer better than other insulation methods.

What is the Best Way to Insulate my Crawl Space?

The best insulation for crawl space is spray foam insulation. Spray foam insulation has a high R-value, increases air quality in your home, and has better thermal performance than other insulation methods. 

Should You Insulate a Vented Crawl Space?

A vented crawl space is insulated to reduce air movement from the crawl space to the living area. A vented crawl space allows the movement of air and causes high energy consumption by the HVAC system. Insulating your vented crawl space is important to make your home energy efficient and comfortable. 

Where to Buy Crawl Space Insulation?

You can get a crawl space insulation kit from the Kraken Bond. We sell Fast Coat products, spray guns, and adhesives you need to insulate your crawl space.

How to Get Rid of Moisture in a Crawl Space?

By insulating your crawl space properly, you can make it free from moisture. Insulation helps control moisture levels and also acts as a vapor barrier. Moisture build-up in crawl spaces can lead to mold growth and the presence of pests and insects. 

Is Crawl Space Insulation Required By Code?

According to the International Residential Building Code, crawl space insulation is essential for both vented and unvented crawl spaces. Crawl space insulation is vital to make your home warm and maintain the structural integrity of the home.


Leave a comment

Please note, comments must be approved before they are published

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Author : Krakenbond Team

    1 out of ...