You should care about your crawl space if you care about your heating and cooling costs, having to walk on cold floors, increased medical bills due to allergy and asthma problems and even how your house smells.
Gases such as radon from leaking up from the crawl space.
There are numerous ways that water can enter your home. The obvious sources are accumulated rain water or storm runoff, but excessive humidity and condensation can also cause enough moisture buildup over time to create significant water damage. One of the most common sources is “hydrostatic pressure” from the ground water that naturally surrounds your foundation and basement walls.
Many building materials that appear solid, such as older types of untreated concrete or masonry, are actually porous and will allow water to seep through. As ground water collects around these artificial barriers, the weight of the accumulated water (hydrostatic pressure) will gradually weaken the material, causing softer areas to buckle or crack and forces water into any available opening.
Basement window wells and invisible gaps between footings and concrete slabs are also vulnerable to water penetration. It takes a surprisingly small about of water to allow mold and mildew to begin forming in basements and crawl spaces. Besides the damp discomfort and health risks, unch
Building scientists and other building experts recommend that crawl spaces be sealed or encapsulated. This upgrade makes buildings more energy efficient and eliminates problems with moisture, mold and pests in the crawl space. Some crawl spaces also need to be waterproofed.
Waterproofing the foundation of your home is vital to ensuring the stability of the structure and protecting the contents that are kept inside. In order to properly waterproof a foundation, it is necessary to not only seal the interior and exterior walls, but also any crawl spaces that may allow for water seepage.
There are several signs that indicate a waterproofing system may be necessary in a crawl space. One obvious sign is standing water on the crawl space floor. If the crawl space has a dirt floor, wet soil can also indicate that a waterproofing system should be installed.
When water collects in your crawl space, it does terrible things to your foundation, to your home’s flooring structure, and to your overall air quality. These are the top three reasons you should eliminate water in your crawl space.
Think of concrete like a sponge. Many concrete structures, both new and old, are porous, especially basement and crawl space walls and foundation supports. Concrete can also become “soft” as it ages, allowing water to seep into crawl spaces. The water passing through concrete will cause expansion and contraction of the block walls, and eventually lead to cracks.
Additionally, your foundation supports can be found in your crawl space and if these sit in waterlogged soil for too long, they will warp, twist, turn, and even worse, eventually lose their structural integrity.
Crawlspace Waterproofing Costs
The cost of waterproofing your basement or crawl space varies, depending on what the contractor needs to do. For each service that the contractor performs, there are additional costs.
Other factors can also affect how much waterproofing your crawl space costs. The factors may include the location of your home, which services the contractor performs, and how much they charge for those services.
A small foundation repair may cost $2,000 but can cost $10,000 or more. If you need a sump pump, that alone can cost $1,000.
If there’s no sump pump basin, that’s an additional expense. If the job requires the installation of drain tile, that project can cost between $8,000 and $15,000.
Encapsulation, the installation of a vapor barrier over the exterior of your basement, is a better option. Basement encapsulation can cost between $2,000 and $15,000.
On average, homeowners pay between $4,000 and $8,000 to have their basement encapsulated. For crawl spaces, it can cost between $2,000 and $10,000 for encapsulation.
Crawlspace Waterproofing Methods
The techniques used to waterproof a crawl space depend on several factors, including the type of foundation you have, where the water is coming from, whether you have a storm drain near your house, and the grade of the soil around the foundation.
A waterproof, condensation-proof vapor barrier is the key to waterproofing your crawl space. This prevents moisture in the soil under and around your home’s foundation from evaporating and entering the crawl space. A vapor barrier is a specially engineered, heavy-duty polyethylene sheet designed to deflect water rather than absorb it.
So we will see now below, that there are two ways to perform the crawlspace waterproofing: exterior and interior.
Exterior waterproofing is the more resource-intensive solution (requires excavation) and helps prevent water from coming into your home by keeping it away from all potential points of entry. Interior waterproofing is often less expensive but can be just as effective as exterior waterproofing
Waterproofing methods may be implemented either on the exterior of your home or interior of the crawl space.
Exterior waterproofing involves digging out the dirt around basement walls, applying a high-tech moisture barrier and installing a specially designed dimple board that deflects water away from the wall. In addition to sealing the wall these materials also improve any structural cracks or foundation flaws that might have been allowing water to get in. The dirt is then replaced with gravel and a drainage system that significantly reduces hydrostatic pressure and helps keep cracks from forming in the future.
This approach stops water at the source and is popular among homeowners that do not want work to be performed on the interior of their home, but it’s also the most labor intensive and costly option. It requires exposing all of the below grade wall surfaces and a lot of hand work to minimize disruption to landscaping and the other outdoor features of your home.
Because excavation is required to waterproof a crawl space from the outside, this technique is considered quite intensive. It’s most feasible to perform exterior waterproofing during the initial construction phase or alongside another renovation, repair or landscaping project.
Exterior waterproofing involves installing a moisture barrier around the foundation walls to keep water out. A drainage system is also often installed to help reduce hydrostatic pressure on the walls that can cause cracks to form over time.
Less costly interior waterproofing is often just as effective as exterior techniques with less disruptive action required. First, it involves installing a vapor barrier on the dirt floor, partway or all the way up the walls, and sometimes even the ceiling. This is known as crawl space encapsulation, and it helps keep all exterior moisture out.
Depending on the age, location or construction method of your home, exterior waterproofing may be the best or only way to go and some contractors may try to convince you that interior waterproofing is an inferior approach. That used to be true, but recent advances in technology have made today’’s interior treatments a lot more reliable than and just as effective as exterior waterproofing. In many cases using them can save you a lot of money.
Interior waterproofing allows you to skip all the expense and inconvenience of exterior excavation.
Then, other methods may be used to remove water and dry up any residual moisture in the crawl space, including running a sump pump, dehumidifier, ventilator or gravity discharge system. Using a combination of interior waterproofing techniques may prove most effective.
Detecting Problems And Preparation For Crawlspace Waterproofing: My Checklist
Detecting moisture problems as early as possible gives you the chance to remedy the issue before irreversible damage is done. Unfortunately, a vast majority of crawl space water leaks go unnoticed for a long time because this is among the least visited areas in your home.
To make sure you catch leaks promptly, plan to inspect your crawl space about twice a year – once in the spring and again in the fall. When you do, watch for these signs that you need crawl space waterproofing:
- Standing water after a heavy rain. Water in a crawl space after heavy rainfall is also a common problem if ignored. Sometimes the ground becomes so saturated, it can’t hold water anymore. Water will pool around your home if this is the case, and water could flood into the surrounding areas—your basement, and your crawl space. Additionally, surface water flooding is a result of heavy rainfall, but could be a problem if downspouts are not turned away from the house. Water from heavy rainfall should be directed away from the foundation of your home.
- Musty odor
- Mold and mildew growth
- Insect or rodent infestation
- Rusty pipes or ductwork
- Wood joists that are rotting, issues in older 2×4 and 2×6 joists that would need to be sistered in some way.
- White deposits on the crawl space walls
- Peeling paint on your home’s exterior
- Air quality problems throughout the house
- Condensation, where it looks like your foundation walls are sweating. Warm air can hold more water than cold air, so naturally, when warm air is cooled, humidity reaches its dew point—the temperature at which atmospheric moisture reaches saturation. Air outside is cooler than the air inside your crawl space. If low temperatures are entering the crawl space through a vent, the warm air is being cooled—therefore posing a problem.
- Cracks in the walls, floors, or mortar joints (area between blocks), what can be caused by hydrostatic pressure.
- A high water table.
- Broken water heater that is leaking or that should be discarded.
Before waterproofing your crawl space, you must address any issues. To begin with, you must mitigate combustion, drainage, or mold problems.
Improper drainage around your foundation is a problem. It can indicate unsatisfactory grading or an unmaintained drainage system. Such conditions can allow water into your basement or crawl space. If you see standing puddles in your basement or crawl space, you’ll need to hire a structural engineer to resolve the issue.
You also need to watch out for mold growing in floor joists or your HVAC equipment. You cannot encapsulate your basement or crawl space before taking care of this matter.
You should also have your contractor check for back-drafting from combustion appliances. This inspection will ensure that your gas furnace and water heater are not giving off carbon monoxide.
Don’t encapsulate your crawl space or basement before attending to this matter. Leaky appliances can filter dangerous gases into your household. Most homes don’t have these kinds of problems, but it’s better to be safe than sorry.
Either way, you want to deal with these problems before the contractor starts their work. Encapsulation can trap mold – for instance – in your basement or crawl space.
A competent contractor will always inspect your basement or crawl space for mold beforehand. They will also check whether your gas furnace or water heater is giving off carbon monoxide.
Now, you know there’s no mold and you don’t have to worry about gas back-drafting into your house. Once the contractor verifies that your basement or crawl space is clear of all threats, they can begin the encapsulation project.
Steps For Waterproofing The Crawlspace
STEP 1: DEBRIS IS REMOVED FROM THE CRAWL SPACE
There’s rarely a true ‘floor’ in a crawl space; most of them are simply dirt under your house. Because of this, builders often place a vapor barrier on the ground when they build a home. A vapor barrier is a sheet of plastic liner that is placed in your crawl space. It isn’t attached to anything; it’s simply a physical barrier to help block out the odors and vapors that evaporate from the earth.
To cover the dirt/gravel floor, a 20 mil. reinforced polyethylene vapor barrier is installed.
Over time, this vapor barrier deteriorates, shifts when water intrudes, gets moved when repairs to pipes or other utilities are made, and stops being effective. Most vapor barriers lose functionality after 5-10 years, depending on how damp your crawl space is.
If you have fiberglass insulation in your crawl space, there’s a good chance it’s no longer in place. In the past, builders thought this was the best type of insulation for a crawl space; we’ve since learned this is not true. Fiberglass insulation absorbs moisture like a sponge, gradually gaining weight until it falls down.
Your old vapor barrier, falling insulation, and any other miscellaneous debris should be removed before water drainage is installed.
STEP 2: DIG A TRENCH ALONG THE PERIMETER OF THE CRAWL SPACE & INSTALL DRAINAGE
Water drainage should be installed along the inside perimeter of your foundation. This will allow the drainage to collect the water as soon as it seeps into the crawl space. You’ll notice the fuzzy outer coating on the geochannel track (in the pictures above). This is a type of fabric developed specifically to filter out dirt, sand, and other detritus; this is what prevents the system from clogging.
The trench is dug, lined with pea gravel, then the geochannel track is placed. Soil or gravel is used to fill around the track and to help “set” it into place.
Trenching is usually done around the perimeter of the crawl space and throughout it. Then, corrugated drain pipe is placed into the trenched areas. We will then fill the trench with lava rock so dirt will not clog the sump pump.
STEP 3: GEOCHANNEL DRAINS INTO THE SUMP PUMP
Now, any water that comes in along the base of the foundation will seep through the filter and into the geochannel. The geochannel track will collect and drain the water into a “pit” that holds the sump pump.
When enough water collects in the pit, the sump pump comes on and expels the water out of the crawl space through a drainage line.
Interior Drain Tile can be installed to address seepage through the cove joint (where the floor and wall meet) or through floor cracks.
STEP 4: REPLACE VAPOR BARRIER OR ENCAPSULATE
Once the water drainage system is installed, you have two options: install a new vapor barrier or encapsulate the crawl space. solutions depend on the cause of the problem and can range from encapsulation to using a sump pump, dehumidifier and perimeter drain system. Our sump pumps are designed to handle major water volume and we have battery backup systems available to keep your basement dry during a power outage.
A vapor barrier is the minimal choice; the plastic liner will help reduce moisture, gases, and vapors from getting into the crawl space. A vapor barrier will also stop rodents from making a home there, help your house stay at a steady temperature and lower your electric bills. It will also improve air quality and help eliminate gases such as radon from leaking up from the crawl space.
But the ideal option is encapsulation. There are three major benefits to encapsulation:
- White cap will block all of the nastiness that evaporates from the ground from getting into the air you breathe
- It protects your wooden flooring structure from moisture, which causes mold and decay.
- It improves the efficiency of your home’s HVAC systems, extending the life of those utilities while saving you money on monthly bills.
Encapsulation uses a much heavier liner than a vapor barrier. Vapor barrier plastic is 3-6 millimeters thick and lasts 5-10 years. White cap is 20 millimeters thick and lasts 25 years. (At Acculevel, encapsulation comes with a 25 year warranty.)
The encapsulation liner completely encloses the crawl space, and all seams are tightly sealed. This liner is also run up the walls and sealed to the wooden flooring structure, using spray foam insulation.
Lastly, if you encapsulate your crawl space, you need to install a dehumidifier. This may be confusing to you- haven’t you eliminated the moisture?! But in some areas, there’s no way to completely remove it without the addition of a dehumidifier.This is because of the wide temperature variations we experience. When it’s warm in your crawl space and cool outside – or vice versa- condensation will form on the liner. That condensation works just like the water that was seeping through your foundation; it will collect and feed mildew or mold. A dehumidifier will eliminate that, and the water line can be drained into the sump pump pit.
If you have termite insurance or a warranty as a part of termite control service contract, you should check the insurance policy or the aforementioned service contract because encapsulation process does not enable a physical termite inspection, thus voiding the warranty or extinguish the insurance policy terms. For this reason, encapsulation can only cover the ground and the blocks. All wood floor should remain exposed in order to supress humidity.
Step 5: Cracks In The Wall Of The Crawlspace
Foundation wall cracks can be repaired from the interior or exterior by using an Epoxy/Urethane injection process. And Exterior Waterproofing Membranes can address the problem of porous concrete walls or seepage over the top of the foundation.
Preventive Maintenance: What To Check After Crawlspace Waterproofing
Encapsulation isn’t the end of caring for your basement or crawl space. You must completely seal the floor, walls, and vents. The goal here is to create an envelope that protects your home from the outdoors.
A plastic vapor barrier attached to the foundation, walls, piers, and mechanical equipment will do the job. It will keep moisture out of your crawl space and out of your critical mechanical appliances.
In addition to attaching a barrier to the walls and piers, you should also have your contractor protect your air handler and water heater. The same applies to any vents or openings that lead outdoors.
The vapor barrier will prevent humid outdoor air from entering your basement or crawl space. For example, a contractor can seal off crawl space vents with foam board and spray foam insulation. They can also attach foam boards to the crawl space door.
Next, the contractor will attach foam insulation to all crawl space walls. Finally, they will air seal all cracks and gaps with spray foam, such as AC drain lines and band joints, as well as plumbing and electrical wiring openings.
Water Damage And Insurance Coverage
Oftentimes, water damage that is found in areas like a crawl space are caused by leaky pipes, flooding from groundwater or run off from rainfall. Knowing the source of your water damage is the first step you will want to take when assessing the damage and figuring out what needs to be done. If the damage in your crawlspace is caused by water seeping up through the ground or coming in at ground level then standard homeowners insurance will not cover the costs. If you believe the chances are high that you could potentially deal with flooding in your crawl space then you will want to add this type of insurance to your homeowners policy. If you have leaky pipes however, homeowners insurance will be more likely to cover some or all of the costs. This will be dependent on whether or not the leak was sudden or over an extended period of time. Damage caused by slow leaks in your piping system are considered to be improperly maintained and will most likely result in lack of coverage whereas a sudden burst in the pipes or plumbing malfunction is usually covered.
Insurance Premiums And Mold: Waterproofing To Avoid Mold Damage In Your Crawl Space
It’s normal to have some water in your crawl space, especially if there was just a rain storm but any water that gets into the crawl space should be able to evaporate fairly quickly otherwise the likelihood of mold growth increases. Stagnant water allows for moisture to build up and where there is moisture you are sure to find the growth of mold. Mold is destructive because its spores travel quickly and are a health concern for humans. As mold grows underneath your home in the crawl space, the air that circulates from your crawl space eventually finds its way into your home. This is the air that you breathe and for those who have asthma or other breathing restrictions, mold spores can be dangerous. When it comes to homeowners insurance, coverage for mold damage will be dependent on the cause of mold. If mold was caused by a flood then the coverage would fall underneath one’s flood coverage plan which is not typically standard. If the mold damage is caused by what is considered a ‘covered peril’, an event that damages a home or belongings, then it may be covered but the likelihood of coverage is grim. Most insurance policies do not cover mold damage due to moisture, flooding or preventable leaks.
Check also the insurance policy in case that there is protection against termites. Encapsulation that is not properly done will not allow a proper termite inspection and this might jeopardize the protection received from the insurance contract in case that the insurable event occurs. For this reason, encapsulation can only cover the ground and the blocks. All wood floor should remain exposed in order to supress humidity.
Homeowner’s insurance policies are known to have lots of loopholes. The best thing you can do for you and your family is to educate yourself on what your insurance plan covers and then add anything to it that you may feel you or your home may be at risk of. If you live in a wet climate, looking into a plan that covers mold damage may be a good idea. If you live on farmland where you know you will be surrounded by wildlife, then you may need to look into a plan that covers damage caused by vermin. Understanding the risks that surround your home and property are key in deciding which homeowner’s insurance plan is best suited for you and your family.
Materials Needed to Waterproof The Crawlspace
A perimeter drain pipe is designed to capture crawl space wall and floor seepage.
A perimeter drainage system works by capturing and navigating the water from the crawl space dirt floor, foundation or walls to a sump pump via underground pipes along the perimeter.
By installing an interior drainage system you’ll be capturing the water at it’s most common entry point while avoiding clogging from soil and roots with exterior versions.
For a dirt floor crawl space – The system features a filter fabric with holes on the front and top to accept the water from the soil.
One of the best ways to protect your crawl space is with the help of a waterproof membrane or vapor barrier. This plastic sheet’s material usually 20 millimeters thick is responsible for permanently preventing moisture, outside air and pests from entering.
This waterproof membrane vapor barrier is laid across the entirety of the crawl space floor and up the walls. This barrier works in conjunction with drainage mats, insulation and vent covers.
If water penetration is serious a sump pump might be a necessity. These machines are designed to move water out of your home. We recommend a pump with a high-quality 1/3hp Zoeller pump which is found in most other pump packages.
I like those models that include battery backup that keep working even when the power goes out.
Flood Alert System: Built into some of the lids is a water-sensitive alarm. This alarm will alert you if water has reached the top of the sump pump’s lid. This can most definitely save you from a huge water disaster.
Vapor Barrier Integration: The vapor barrier used for crawl space encapsulation only works if the area is air tight. That is why a sump pump with a special lid that integrates with vapor barriers for an airtight fit is important. If bunching in the membrane were to occur this can allow for water to pool and not be able to reach the drain.
A dehumidifier will dry out a damp crawl space and automatically maintain a pre-set humidity level. By controlling crawl space humidity, you create conditions that are hostile to mold and mildew.
After insulating and encapsulating your crawl space, the next step for waterproofing would be to install a dehumidifier. The tricky part is finding one small enough to fit but strong enough to remove upwards of 90 pints of water a day. Not mention your crawl space is often cold so this dehumidifier needs to work efficiently in lower temperatures.
This dimpled plastic sheet material promotes good drainage over the entire crawl space floor.
You can put it beneath the vapor barrier, or you can just use the vapor barrier without the addiional draining matting, and that is fine. Some homeowners use the vapor barrier and the drainage matting only in some critical areas of the crawlspace.
Vacuum To Remove Water
Invest in a wet-dry vacuum. If your wet crawl space is a minor issue, meaning there’s not much water present, use a wet-dry vacuum to remove the water. A hose draws the water into the vacuum compartment to be discarded outside.
Don’t allow your crawl space to air dry after this step. Concrete is much cooler than other materials, so it holds moisture longer, and wood absorbs water almost as easily as sponge. Even if you have the pools of water cleared out, moisture will be left behind.
Use a dehumidifier to quickly dry out the space. This will remove moisture from the air and prevent mold growth.
Simply cleaning out crawl space water, however, will not prevent any issues from resurfacing in the future. There are some other problem areas to check and possibly fix in order to prevent water in a crawl space.
Reasons To Perform The Crawlspace Waterproofing
Homeowners are advised to waterproof their crawl space for several reasons.
CONTROL THE TEMPERATURE
High humidity in the crawl space affects the temperature throughout the rest of your home, making it feel colder or hotter than it should be. This may force you to run the furnace or air conditioner more just to stay comfortable.
A waterproofed crawl space is cool and dry, so it has a much smaller effect on home comfort. As a result, you save on energy costs by reducing the amount your HVAC system runs.
IMPROVE INDOOR AIR QUALITY
Up to 50 percent of the air in a crawl space can flow up into the living area. If the air is damp, moldy and fumy, this can obviously impair your indoor air quality. Sensitive individuals may even suffer from headaches, respiratory distress and allergy symptoms as a result of overexposure to moldy air.
When your crawl space is clean and dry, mold growth is hampered. This keeps harmful spores away from your family’s lungs so everyone can breathe easier.
PROTECT YOUR HOME’S STRUCTURAL INTEGRITY
Encapsulation will improve the structural integrity of your home because it is working to keep the soil dry. Dry soil supports a house compared to damp or wet soil that could shift and damage foundation supports overtime.
Excess moisture can rot wood, rust metal and damage drywall. It also makes the ideal environment for mold and termites, which can eat away at your home’s structure. If left unaddressed, your floor joists may degrade to dangerous levels, resulting in sky-high repair bills.
Adding a vapor barrier to the crawl space deters moisture from entering. This gives you peace of mind that your home is well protected from the ravages of wood rot, mold growth and termite infestation.
Saving In Energy Bills
Moisture in the air is usually due to hot, humid conditions, and this makes it very difficult to cool your home in the summer. If humid air sits below your floors in the crawl space, cooling the rest of your home takes more energy, therefore more money. Encapsulation along with waterproofing will decrease the humidity level beneath your home, creating a significant difference in your energy bills.
PROTECT YOUR STORED BELONGINGS
One major benefit of a crawl space is that it increases home storage. However, if water regularly pools on the floor and mold growth runs rampant, the items you store here could be ruined, leaving you distraught when you go to retrieve your keepsakes or heirlooms.
Waterproofing ensures the storage space under your house remains a reliable place to hold precious belongings without fear of losing them to water or mold damage.
REDUCE ELECTRICAL HAZARDS
Moisture and electricity don’t mix. If you have wiring running through your crawl space, water problems could cause electrical shorts, rusted wires or even a house fire.
Ensuring your electrical system is free from moisture is critical for maintaining your family’s safety. If you notice problems with your wiring, consider waterproofing the crawl space to decrease the risk of electrocution and fire.
PRESERVE PLUMBING & DUCTWORK
You probably have water pipes, sewer lines and air ducts traveling through the crawl space. This placement makes them easy to maintain and repair, but if the humidity is too high, rust may become a problem. Over time, corrosion may cause pipes to burst or ductwork to fail.
Extend the life of your plumbing and air duct systems with crawl space waterproofing.
MAINTAIN YOUR HOME’S VALUE & INSURABILITY
All of the problems associated with excess moisture in the crawl space – including mold growth, structural damage, poor air quality and comfort issues – can affect the ability to sell your house in the future. Even if you don’t plan to move, homeowners insurance may be harder to come by if you have a waterlogged crawl space.
A vapor barrier in the crawl space may not directly increase home value, but it prevents problems from developing that could have a negative impact. In this way, crawl space waterproofing is a wise investment that proves to be worth every penny.
Act Against Condensation
Condensation under the house is a problem for some homeowners. It can be a result of leaking ductwork or poor ventilation in the crawl space, or, sometimes outside air coming in through the vent. How is this possible? Warm air can hold more water than cold air, so naturally, when warm air is cooled, humidity reaches its dew point—the temperature at which atmospheric moisture reaches saturation. Air outside is cooler than the air inside your crawl space. If low temperatures are entering the crawl space through a vent, the warm air is being cooled—therefore posing a problem.
Supression Of Mold And Pests
Waterproofing will reduce the chances of mold in your crawl space significantly. Mold and bugs thrive in wet places and can spread throughout the home, increasing chances of wood rot and other potentially hazardous effects.
No More Animals Burrowing Or Digging Near the Foundation
Crawlspace waterproofing is one of the things in the checklist to do against these animals, another one is to monitor the hydrostatic pressure in the basement and to check if there is stagnant water after a heavy rain inside the crawlspace.
Results Expected After Waterproofing The Crawlspace
- Odor reduction in the crawlspace as well as the entire home
- Many moisture issues within the home solved
- Increased storage space, 85% of buyers look for storage space when buying a new house
- Healthier air with less airborne mold
- Increased property value because your beautiful crawlspace will be a clean area for storage
- Eliminates black mold and moisture from within the crawlspace.
- Greatly improves indoor air quality within the crawlspace and throughout the entire home
- Reduces the number one source for entry of radon gas into the home
- Protects against allergens dust mites throughout the entire home
- Seals out most bugs, spiders, rodents and termites from the crawlspace
- Insulates the crawlspace and reduces energy costs. Many times crawl space repairs will pay for themselves within the first 12 months
- Protects the structure of the home from dry rot and termites
- No more crawl space musty smells from moisture and mold