proper humidity for crawl space

Stop Crawl Space Dampness in Its Tracks: Dehumidifiers for Multi-Family Homes

Have you walked onto your property and been greeted by a musty smell that hits your nose sometimes? It likely means there's too much dampness in your building's crawl space. And dampness leads to issues like mold, wood rot, bugs, and stale indoor air.

As a property manager, letting crawl space moisture build up can mean expensive repairs. We're talking about potentially replacing moldy floors, beams rotted through, and more.

Protecting your investment and keeping residents breathing easy is a must.

This guide covers simple solutions for controlling crawl space humidity using dehumidifiers. You’ll learn how to keep your crawl space dry, and your tenants happy.

Understanding Crawlspace Humidity

What exactly is the crawl space? It's the small area between the dirt and your building's first floor. Unfortunately, crawl spaces are prime spots for moisture troubles from:

 1. Groundwater sneaking in through floors or walls

  2. Leaks from pipes or water lines running through

  3. Condensation from warm air hitting cooler surfaces

Too much moisture in this enclosed space creates a nasty recipe for problems like:

  1. The mold that spreads quickly on organic materials

  2. Wood rot weakening supportive beams and flooring

  3. Pests like termites and carpenter ants moving in

  4. Mildewy odors and mold spores getting inside living areas

The proper humidity for crawl spaces is 45-55 %. Getting moisture under control is important for protecting your property's condition and air quality. In other words, you need to dehumidify the crawl space! Commercial dehumidifiers work great in this situation and they are easy to implement.

Crawl Space Dehumidifier Solutions

Dehumidifiers are moisture-removing machines and are often the ideal fix for crawl space dampness. They work by pulling in humid air and extracting the excess water vapor. The dried air then gets released back into the space.

There are two main types well-suited for crawl spaces:

Refrigerant Dehumidifiers - These cool the air until it can't hold as much moisture, similar to your AC unit. They are highly effective in warm, humid conditions—however, their performance drops at lower temperatures below 65°F.

Desiccant Dehumidifiers - Instead of cooling, these use materials that absorb moisture from the air as it passes through. This option is expensive upfront but works better in cooler spaces than refrigerant units.

When shopping for an energy-efficient crawl space dehumidifier, look for models with the ENERGY STAR label. Features like auto-restart after power outages and adjustable humidity controls help cut costs.

Proper sizing is key for a dehumidifier to work its best. Sizing is based on the total square footage of the crawl space, plus factors like:

  Average humidity levels - very damp areas need more muscle

  How drafty or sealed off the space is

  Any constantly wet areas from leaks

Installation and dehumidifier placement are also important. Make sure you have proper drainage set up to remove collected water. Allow enough clearance around the unit for good air circulation. Use additional fans if needed to prevent stale air zones.

Keeping it Running Smoothly  

Once installed, dehumidifiers do require some routine care and maintenance. You can’t just expect to "set it and forget it!"

Clean Air Filters Regularly -A clogged filter blocks airflow, straining the unit and reducing performance. Check every few months and clean or replace as needed.

Check Drainage System - Clogs or malfunctions in drain lines, pumps, or pans can cause water backups and overflows. Make sure drainage is working properly.

Watch for Performance Issues -Be on the lookout for abnormal noises, leaks, or airflow issues. These can signal the need for service.

Monitor and Adjust Settings - Don't just set the humidistat and ignore it. Routinely check moisture readings and dial in the ideal humidity set point, typically 30-50%.  

Integrate HVAC Airflow -For even better efficiency, link the dehumidifier with your overall HVAC system. This optimizes air circulation and makes the most of dehumidification.

Smart Operation Saves Money - Program humidistats to avoid over-drying. Use fans to enhance airflow without running the dehumidifier more than needed.  

Following best practices for filter changes, settings adjustments, and ongoing monitoring helps ensure your dehumidifier runs smoothly for years.

Additional Steps to Control Moisture

In very damp crawl spaces, you may need to pair your dehumidifier with an additional moisture control tactic. Here are a few suggestions:

Improve Ventilation - Adequate airflow is key for effective dehumidification. Install vents or fans if needed to enhance cross-ventilation. Just be cautious of introducing more outdoor humidity.

Seal Up and Insulate -Thoroughly seal off any openings or cracks in the crawl space. Proper insulation also moderates the space's temperature.  

Fix Groundwater Entry Points - If moisture seems to be wicking up through the floor, try solutions like vapor barriers, sump pumps, or waterproofing sealers.

Repair Any Water Leaks -Drips or spills from plumbing pipes and drains add lots of moisture fast. Promptly fix any active leaks.

Dehumidifier in Crawl Space Without Encapsulation - For moderately damp spaces, a stand-alone dehumidifier can sufficiently control humidity without the added cost and effort of fully encapsulating the crawl space with vapor barriers.

Full Encapsulation - For ‘wet” crawl space environments, you can install a full plastic vapor barrier along floors and walls paired with dehumidification equipment.   

Using an integrated approach customized to your crawl space gives the best results for resolving stubborn dampness concerns.  

The Smart Investment

You might cringe at the upfront costs of a dehumidifier, which typically range from $450 to $1,600 for a quality crawl space unit and professional installation. But think of it as an investment that pays you back over time in protected property value. Depending on the situation, a dehumidifier can be a cost-effective alternative to full crawl space encapsulation.

Getting moisture under control now prevents future expensive headaches like:

- Hazardous mold removal projects costing tens of thousands  

- Replacements of rotted structural elements in floors and beams  

- Lost rent income and high turnover from unhappy tenants

Beyond just avoiding damage, dehumidifiers also deliver benefits like:

- Reduced energy usage from optimized HVAC operations

- Extended lifespan for your building's structure and materials

- Attractive, comfortable living conditions that keep tenants satisfied

Over just a few years, the elimination of constant moisture woes quickly recoups the upfront costs through savings across repairs, operations, and occupancy rates. Proper dehumidification is a savvy investment!

Final Thoughts

Damp, musty crawl spaces spell trouble for multi-family property managers. But with smart dehumidifier solutions, you can stop moisture issues before they escalate into costly nightmares.

The AlorAir Sentinel HD35P is a 35-pint per day dehumidifier designed specifically for crawl spaces and basements.  It features a compact, durable design and can effectively remove excess moisture from spaces up to 1,000 square feet.

The Sentinel HD55P is a larger 55-pint per day model suitable for spaces up to 1,300 square feet. Both units are energy-efficient, with the HD55P offering a 17% improvement over the previous HD55 model.

AlorAir is a leading manufacturer of commercial and industrial dehumidification equipment. Founded in 2003, our mission is to provide innovative solutions that improve indoor air quality and control moisture in challenging environments.

In addition to dehumidifiers, we also offer a range of related products like air movers, air scrubbers, and crawl space encapsulation materials. Our company is committed to developing high-performance, energy-efficient equipment to meet the needs of HVAC contractors, restoration professionals, and facility managers like you.