The average crawl space dehumidifier costs $7,000, but it can range between $3,000 and $9,200, depending on the size of the crawl space and the dehumidifier purchased.
Installing a crawl space dehumidifier costs $7,000, though the project can range from $1,500 to $14,000 depending on several factors. Crawl space dehumidifiers lower humidity in your home, preventing mold, mildew, and wood damage. They also improve air quality, reducing the number of allergens.
Installing a dehumidifier in a crawl space without encapsulation isn't recommended as there would be too much air infiltration, making the dehumidifier work much harder. For this reason, we've priced this page assuming you need crawl space encapsulation as well as the dehumidifier. If your crawl space is already encapsulated, expect to pay around $3,000 to buy a unit and have it installed.
The type of dehumidifier you choose and the size of your crawl space are the main drivers of what you’ll pay.
| Desiccant | Cooling-based | Hybrid |
|---|---|---|
| Uses a drying agent | Uses compression to condense moisture | A combination of desiccant and cooling-based |
| Effective across all temperature ranges | Less efficient in cold weather | Harder to find |
| Quieter | More powerful | More expensive |
The type of dehumidifier you choose may be based primarily on budget and functionality. The unique needs of your space will also determine which type to buy, but there is one type that is clearly more popular—coolant-based dehumidifiers.
Refrigerant dehumidifiers, also called coolant-based dehumidifiers, are popular for several reasons. First, they are less expensive than desiccant models. They may be louder, but they force a lot of air quickly, which can quickly and dramatically lower humidity in your home. Expect to pay around $1,500 for a refrigerant-based model for an average-sized crawl space.
Desiccant units are more expensive (around $2,000 on the higher end) and don’t tend to work as quickly as refrigerant units. However, they may keep a space's humidity more stable over time, which has benefits. You can also opt for a hybrid of the two, but those are harder to find and more expensive.
Dehumidifiers are classed by how much moisture they can extract from the air in a single day. The dehumidifiers you may be used to, such as those used in bedrooms or other living spaces, are typically between 25 and 30 pints. However, these are much too small for a crawl space.
There are some strategies you can use if you want to maximize the dehumidifier's effectiveness. A great way to save money while ensuring your unit outperforms is to buy and install one that is one category up from the size you need. The reasoning is the larger the unit, the quicker it can remove the humidity. They also run less, which means lower electricity bills.
| Crawl Space Size in Square Feet | Dehumidifier Water Capacity (Pints) | Average Cost |
|---|---|---|
| Up to 1,500 | 30–50 | $150–$600 |
| 1,500–2,500 | 50–70 | $450–$1,400 |
| 2,500–3,500 | 70–120 | $1,400–$2,500 |
| 3,500+ | 120+ | $2,500–$4,000 |
If your crawl space is already encapsulated, you won’t need many materials. Installing a dehumidifier involves securing it to an immovable object like a part of the foundation or a wooden beam. The drainage system needs to be set up, but oftentimes, this is rather simple. The final piece of the puzzle is power. Ideally, there is a large socket nearby where you can simply plug in the unit. Many of them, however, need to be wired, which is where a pro comes in.
Installing a dehumidifier can be as simple as getting it in place and plugging it in, but those are rare cases. Usually, there are hiccups that you should lean on a pro for. Expect to pay professionals between $50 and $120 per hour for installation.
If your crawl space isn’t encapsulated, you’ll need to do that. It’s a project that takes quite a while and involves specialized equipment, so it isn’t something you should DIY. Once that’s completed, prepping for a dehumidifier comes down to making sure there is power in the area, accessible drainage, and a clean space to mount the unit.
Crawl spaces are small areas, which makes them difficult to work in for extended periods. It’s understandable why it would cost a premium to perform work in such a space. While HVAC professionals will be used to the tight quarters, you can still expect to pay a bit more compared to work done where you can stand and aren’t constantly bumping into things.
This “comfort premium” is baked into the cost of labor, so you won’t see it on a cost line. However, expect to pay between $50 and $120 per hour for the labor.
Most dehumidifiers won’t need much routine maintenance. After all, a dehumidifier in your crawl space will have its own drain line, meaning you won’t need to physically empty a reservoir. However, you should still change the air filters when required—usually every three to six months. When you’re down there, clean the coils and run the unit, making sure it drains properly and nothing is loose. Homeowners should have a pro check the unit every year to 18 months.
Dehumidifiers use a lot of electricity. Energy-efficient models are best, but homeowners can still expect an annual electrical bill increase of around $300 to $500. These numbers can drop if the crawl space is properly encapsulated but could easily surpass the higher end in moist climates without a proper crawl space seal. If possible, program the machine to run primarily at night, when electricity tends to be less expensive.
Dehumidifiers are simple machines that are not too expensive to repair. The good news is that most repairs will only require a few hours of a professional’s time, meaning you save on labor. The bad news is that certain parts (like compressors) can cost up to 50% of the price of the entire unit to repair. Performing regular maintenance can help prevent costly issues from arising.
While you can install a dehumidifier in your crawl space yourself, we recommend hiring a pro. It isn’t a total necessity—like it would be for mold removal—but it ensures the unit is installed correctly and will operate at maximum efficiency.
While hiring a pro increases upfront costs, it may ultimately save you money by preventing costly repairs arising from improper installation. Another note: DIY installations often void the dehumidifier's warranty. Contact a local HVAC professional to determine the size of the unit you need and how much it will cost to purchase and install.
There are not too many ways to save money during an installation, so you need to get creative. Don’t expect to save anything like 50% of the cost, but some ways you can start shaving down the total are:
Choosing energy-efficient models.
Testing the seal of the crawl space, ensuring 100% coverage.
Set the unit to run at low-cost energy hours.
Schedule regular maintenance.
Shop around and take your time finding the right unit.
Remove any items that can increase or trap humidity.
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A crawl space is an area under the house that provides access to plumbing, electrical, heating ducts, and other HVAC units. Its purpose is to create a buffer between the ground and the living area, helping with ventilation, moisture control, and access for maintenance or repairs. Crawl spaces are most often seen in houses in North America which are built on concrete foundations versus other parts of the world where buildings are constructed differently.
Some disadvantages of crawl spaces are mostly regarding the air itself—moisture build-up and poor ventilation, which can cause problems both in the house and underneath it, even damaging the foundation itself. Crawl spaces are difficult to access and often invite unwanted pests during the hot summer months and the cold winter ones. These hard-to-seal spaces are also susceptible to water damage during periods of heavy rain or melting snow.
The only real negative when encapsulating a crawl space is that the cost is high. It can cost several thousands of dollars to do this project. However, it protects your house and those in it by providing an energy-efficient space instead of one that frequently pools moisture and causes damage through mold growth in your home. While less common, another disadvantage could be encapsulation making access to pipes and electrical slightly more complicated in certain crawl spaces.
