Crawl Space Encapsulation Pros and Cons

It is clear that homes with unconditioned crawl spaces will see more long term moisture related issues over time. Extended periods of high humidity in the crawl space can lead to cupped hardwood floors, mold growth, water damage and wood rot. To avoid these issues, experts recommend crawl space encapsulation. Understanding the pros and cons of crawl space encapsulation is important in determining if this type of vapor barrier works in your situation. When choosing a crawl space system, know the advantages and disadvantages.

Here are a few crawl space encapsulation pros and cons that you should consider before installing one in your home. Home owners with slab foundations need not apply. We also included a few Do’s and Don’ts when it comes to encapsulating the crawl space. Lastly, we discuss the key differences between encapsulation and installing a standard crawl space vapor barrier. This will help you answer the question, do the benefits of crawl space encapsulation outweigh the cost of installation?

The Benefits of Crawl Space Encapsulation

There are many benefits of crawl space encapsulation. The investment is well worth it when you consider these items.

Reduces/Eliminates Moisture Problems in the Crawl Space

Humidity is a problem that every home faces. With the help of proper crawlspace sealing, excessive moisture, high humidity and structural damage issues are reduced. This protects your home not only from mold and mildew, but also promotes a long life for the structure of your home.

Prevents Crawl Space Pests

High humidity in the crawl space is sometimes associated with certain pest infestation. If installed properly, sealing the crawl space can protect you from termites, rodents and other wildlife looking for a home.

Reduces Overall Heating Costs

During the product’s life, you can expect lower heating and cooling costs. This is because the cracks and gaps that usually let air escape are sealed. By insulating the foundation walls instead of the floor joist cavity, the HVAC system will run less. This reduces wear and tear on the HVAC equipment. It also increases energy efficiency and saves money.

Reduces/Eliminates Crawl Space Odors

One of the biggest contributors to foul odors in your home is the crawl space. The encapsulation process will include cleaning and prepping your crawl space or. Your home will no longer linger with crawl space smells associated with mold mildew after encapsulation

Reduce Dust In The Home

A home with a traditional vented crawl space has air that comes in through the foundation vents. This air then exits out the ridge vent on the roof. This process is called the “Stack Effect.” This air contains dust and pollen that can contribute to poor indoor air quality. Encapsulating the crawl space helps reduce the stack effect. It seals all the openings where polluted air can enter. This action stops the thermodynamic engine that pushes air up into living spaces. It also improves indoor air quality.

Increases Home Value

When asked, home buyers prefer an encapsulated crawl space compared to homes with traditional vapor barriers. An encapsulated crawl space is a premium item. It takes a usually dark, damp and foreboding area and transforms it into a clean, dry visually appealing space. The thick reinforced liner is more forgiving to the wear & tear of heavy handed contractors.

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Cons of Crawl Space Encapsulation

You can not have a discussion about the pros and cons of encapsulating crawl space without listing the cons. We discussed the benefits of crawl space encapsulation. Time to consider a few negatives to encapsulating the crawlspace. Consider these factors before making your final decision

Upfront Investment

According to Home Advisor, the cost to encapsulate a average crawl space range between $3.50 to $7.50 a square foot. This puts the average cost at $5,500 to install this system. If you live in dry region, the advantages of encapsulation may not give you the investment return that you seek.

A Cheaper Solution Can Be Just As Effective

Encapsulation is considered a premium moisture abatement solution for your home and it comes with a cost. There are situations where installing a standard vapor barrier and crawl space dehumidifier can be equally effective for controlling moisture in the crawl space at a fraction of the cost.

Cold Floors and Loss of Floor Soundproofing

A typical encapsulation project has the insulation removed from the joist cavity and the foundation and basement walls insulated. The removal of insulation is typically the first step in a crawl space mold remediation project. You often see why crawl space encapsulation and insulation removal are paired together. Removing insulation from the floor joist is typically the first step in a crawl space mold remediation project. Customers can keep undamaged floor insulation instead of putting in new insulation on the crawl space wall. This helps save on project costs.

Customers reported hearing sump pumps and other crawl space equipment and noted cold spots on the floor. Reinstalling insulation in select areas of the floor & foam equipment covers resolves the problem at an additional expense.

Not An Easy Fix!

Materials used to encapsulate the crawl space are specialty items and not readily available at the local hardware store. Quality installers often give a free roll of tape to homeowners. They also provide extra crawl space liner to fix small issues. Major modifications such as new additions & catastrophic plumbing leaks will need the help of your installer at additional cost.

Regular Maintenance Needed

You need a yearly inspection and equipment maintenance. This will ensure the crawl space equipment works as it should and keeps the warranty valid. The cost of maintenance usually depend on the amount of crawl space equipment installed. Cleaning the dehumidifier filter and making sure the sump pump discharge locations are clear are other common tasks.

Encapsulation Do’s and Dont’s

When you’re encapsulating your crawl space, you want to make sure it is installed correctly. Here are a few best and not so best practices when it comes to encapsulating your crawl space.

Seal Gaps and Cracks First

Seal all the gaps and cracks in the walls and subfloor before installing the crawl space lining. After installation, the liner can cover large parts of the crawl space. This may hide areas that need repairs before covering.

Use hydraulic cement to fill cracks in the foundation wall. Also, use it around utility penetrations to stop small water leaks into the crawl space. Use closed cell expandable foam insulation to seal holes in the subfloor. This helps reduce the communication of air between the crawl space and living area of the home.

It is important to seal the crawl space foundation vents when installing a dehumidifier in the crawl space, This blocks the conditioned air from leaking out of the crawl space. Insulation foam board and caulking are commonly used to for this. The more communication

Have a Crawl Space Drainage Plan

Moisture can enter the crawl space in two forms. As a liquid and as a gas. Both forms are addressed separately when sealing a crawl space.

A common misconception is thinking that encapsulating the basement or crawl space prevents water entry or flooding under houses. Consider the encapsulated crawlspace as a vapor barrier on steroids. The job of the vapor barrier is to reduce the transmission of water VAPOR from the ground surface into the crawl space. It does nothing to stop the flow of water through a cracked foundation wall or other preferential pathways during heavy rains.

If you seal the crawlspace without addressing the moisture problem, the water that enters gets trapped under the liner. This causes what is known in the industry as the “Water Bed Effect”. If the seams do not bust open due to the weight of the water, the liner will need to be cut to drain all the water.

An interior perimeter drain with a sump pump is the best way to capture and manage water as it enters into the crawl space.

Encapsulation Vs Vapor Barrier

What is the difference between encapsulation and a vapor barrier? Normally, the thickness of the barrier, the taped seams and how it is fastened to the foundation wall.

Don’t Forget the Dehumidifier:

There are many factors that determine the relative humidity inside a crawl space. The height of the crawl space, the moisture content of the underlying soil and water management both inside and outside all play a part. The amount of duct work leakage also has an effect. Here is the curve ball. The more leakage Crawl spaces with leakAnother common misconception is that once you seal your crawl space misnomer about sealed crawl spaces is that

Installing a properly sized crawl space dehumidifier helps reduce the relative humidity in the air and dry up puddles of standing water.

Alternatives to Crawl Space Encapsulation

The job of any vapor barrier is to reduce ground water from evaporating in your crawl space. A standard unsealed 6-mil or 10-mil black plastic vapor barrier is a lower cost alternative to full encapsulation. This differs from the fully encapsulated crawlspace ashe durability of the liner usually less. Typically, the seams of the traditional vapor barrier are not sealed using vapor bond tape and not attached to the foundation wall to stop moisture from coming through the block. The decision is based on the severity of the moisture problem and the cost of full encapsulation.

The majority of newly constructed homes start with a standard 6-mil black polyethylene contractor grade vapor barrier. Proper installation includes 12-inch inch overlapping seams that are secured to the floor of the crawl space using soil pins. To counteract that, a thin sheet of plastic usually 6-10 millimeters thick that covers 100% the floor of the crawl space. Black and now recently white are the common colors. Clear plastic is usually frowned upon as green algae will be visible under the the liner anywhere light comes in the crawl space.

As a result, water can still bypass the vapor barrier and enter the crawl space through the unsealed seams of the vapor barrier. A dehumidifier installed in conjunction with a standard unsealed vapor barrier has to work harder than its encapsulated counterpart. Moisture passes unsealed seams provide moisture into the crawl space needs to work harder The vapor barrier blocks leof and harder to condition the space. There will always more moisture A comprehensive and expensive approach is to get your crawl space encapsulated and drainage system installed to better guarantee a reduction in moisture.

The process begins with sealing the foundation vents, holes and cracks. The plastic attached to the wall using adhesive & nails This thicker plastic is usually 12 to 20 millimeters thick. It also has a polyester-cored reinforcement which is more durable than the vapor barrier. Vapor bond tape seal seams and is fastened to the floor walls & piers using adhesive. This completes the crawl space encapsulation process

Contact Our Crawl Space Encapsulation Pros!

If you are thinking about moisture control for a wet crawl space or basement, please contact one of our experts for a free estimate today. We also specialize in mold removal for crawl spaces.

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