Hi, I’m AJ Howard from Crawl Space Ninja Supply. Every day, I help homeowners and contractors protect their homes from the top threat to a crawl space: humidity.

If you remember one thing from this article, let it be this: a crawl space dehumidifier is more important than encapsulation alone. Encapsulation without a dehumidifier is like sealing a jar without removing the damp air inside it traps the problem. However, running a dehumidifier in a crawl space that isn’t encapsulated will still greatly reduce moisture and slow damage.

Product Spotlight: See our full line of Crawl Space Ninja Supply Dehumidifiers  professional-grade units designed for maximum efficiency and long life.

The best solution? Both encapsulation and a dehumidifier working together; the barrier keeps moisture from entering, and the dehumidifier removes what’s already there. You will have full control of the temperature and humidity in your crawl space allowing for healthy clean air to be in your living space

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Why a Dehumidifier Without Encapsulation Is a Strong but Challenging Start

Installing a dehumidifier before you encapsulate is a smart first step—it quickly protects your home from excess moisture, mold, and rot. But without encapsulation, you are forcing that unit to fight a much tougher battle than it was meant to handle.

• It has to work harder and longer. Without a vapor barrier sealing the floor and walls, your crawl space will consistently draw in outside moisture through vents, porous block walls, and exposed soil.

• This can shorten its lifespan. The professional-grade dehumidifiers we sell at Crawl Space Ninja Supply can last 10 to 15 years with proper installation and maintenance. But making them run almost nonstop in an unsealed crawl space can greatly reduce that lifespan.

Recommended Models: Our Aprilaire Dehumidifiers and Ninja Dry Pro Dehumidifier are built for crawl space conditions and can handle the toughest moisture challenges.

That’s why combining encapsulation with a dehumidifier isn’t just “better” it’s the setup that allows your investment to last.

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The 60% Rule: When Mold Begins to Grow

Here’s the truth about mold: it won’t wait years to show up. At a Relative Humidity (RH) level of 60% or above, mold starts to grow within 24 hours.

This doesn’t mean you’ll suddenly see a jungle of mold overnight, but it does mean the spores will begin to activate at that point. Once that process starts, it only takes the right temperature and a few days for visible growth to appear.

Keeping humidity below that level is the single most important action you can take to protect your crawl space.

Humidity Control Tip: Pair your dehumidifier with a Crawl Space Vent Fan to keep air moving and conditions stable.

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The Best Time to Install a Dehumidifier in a Full Project

If you’re working on your crawl space all at once—water management, mold removal, and encapsulation the dehumidifier should be running before the barrier is installed. Here’s the suggested order:

Step 1: Crawl Space Prep

Remove debris, old insulation, and damaged materials to create a clean work area.

Step 2: Drainage System Excavation

Dig a perimeter trench for the Hydraway strip drain and a sump pit at the lowest point.
Make sure there is a proper slope toward the basin.

Step 3: Mold Remediation

Treat joists, subfloor, and piers with a mold remediation solution.
Apply the solution with sprayers, brushes, or foggers, allowing enough time for it to work.

Step 3.5: Begin Drying Process

Start the dehumidifier while mold remediation is in progress.
This will dry wood, piers, and soil, leading to better results for insulation and encapsulation.

Step 4: Install Drainage and Pump System

Install the Hydraway strip drain, connect it to the sump pump, and route the discharge line.

Step 5: Insulate Walls and Rim Joists

Install Insul-Barrier on foundation walls, sealing all seams and edges.
Insulate rim joists with foam board or spray foam.

Step 6: Encapsulate Floor and Piers

Install and seal the vapor barrier across the floor, wrapping and sealing piers.
Mechanically fasten the vapor barrier to walls and piers.

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If you can’t complete the full project right away, you can still make significant improvements:

1. Close the crawl space vents.

2. Install a vent fan in one vent to encourage controlled air movement.

3. Remove any fiberglass insulation that can retain moisture.

4. Run a dehumidifier to keep humidity under control while you plan the rest of the project.

Here’s what makes it special:

• Same Coverage as the E070: Handles up to 2,200 square feet of crawl space.

• Same Moisture Removal Power: Removes 70 pints of moisture per day under AHAM conditions.

• Same Warranty Protection: Covered by a full 5-year warranty for peace of mind.

• Quieter Operation: We modified the design to run with less noise, making it one of the most discreet crawl space dehumidifiers available.

• Price Control: Because we produce and sell the Ninja Dry Pro ourselves, we’re able to offer competitive, consistent pricing without outside markups.

 

While the Ninja Dry Pro matches the E070 in specs, the quieter performance and direct-to-customer pricing make it an incredible value. At the time of writing (August 2025), this unit does not have accessory options  it’s sold as a ready-to-use standalone system.

Even without full encapsulation, starting with the Ninja Dry Pro will immediately help protect your crawl space from humidity damage, mold growth, and wood decay.

 

Even without full encapsulation, this approach starts protecting your home from humidity damage right away.