What is a Rotomold Dehumidifier

Rotational molding or rotomolding is a process used for plastic parts that require a high-quality finish, uniform thickness, and high stability. It is often done to create a rugged and durable type of housing for a portable industrial-grade dehumidifier. 

A rotomold is made by heating and rotating plastic in a hollow mold to produce a single piece of seamless plastic structure in the desired shape. This ensures toughness and durability with few stress points throughout the body. A rotomolded dehumidifier can withstand rugged handling and collisions from one job site to the next. It is often made to be portable and stackable for easy transport and storage. However, some disadvantages are the cost and weight of each unit.

If you’re in the industries of building construction or water damage restoration, this type of dehumidifier is a staple in the business. Aside from rotomolded plastic, heavy-duty steel may be used in the dehumidifier’s construction.

Rotomold Dehumidifier Blue Color

When Do You Need a Rotomold Dehumidifier

Rugged, portable commercial dehumidifiers are specifically built for drying and restoring water-damaged sites. Restoration must be done soon after any water damage emergency including floods after heavy rainfall, leaky plumbing, or burst pipes. Stagnant water can be dangerous in residential areas. If left for too long, it can lead to mold infestation or become a breeding ground for disease-causing bacteria. Restoration involves drying equipment like industrial dehumidifiers and blowers.

Rotomolded dehumidifiers are also commonly used in drying new constructions and other moisture-prone commercial spaces like indoor pools, spas, and gyms. These heavy-duty dehumidifiers are equipped to work in extreme temperatures. They can remove moisture from heavily damaged properties and large commercial spaces to achieve the ideal humidity level. To provide a quick and efficient solution, they feature a portable, stackable design and a rugged rotomolded case. 

Advantages and Disadvantages of Rotational Molding

Advantages and Disadvantages of Rotational Molding

Rotomolding is used in making equipment parts for a variety of industries. Some of its advantages over other molding processes are the durability and long-lasting quality of materials produced. However, there are of course some disadvantages, such as the limited material options and higher labor costs.

Advantages of Rotomolding

Wide range of designs and size options – The rotomolding process can easily create a variety of shapes and designs from plastic. Rotomolding also accommodates surface finishes such as fine-detail textures, logos, or symbols.

Consistent wall thickness – The rotation of the mold evenly coats the walls during the heating and cooling processes, producing consistent thickness from all corners. This protects the internal components from collisions during loading and shipping. 

High durability and stability – The entire part is molded as one solid piece so there is no need to join or weld parts together that create stress points. There are also fewer risks of defects in the finished product. This is why rotomolded dehumidifiers are commonly used in various industrial applications.

Disadvantages of Rotomolding

Limited material options – The raw material used in rotomolding must be converted from granules to a fine powder with high thermal stability. This limits the material options to poly-based resins such as polyethylene or polythene.

High costs of labor and raw materials – Due to the limitations set by the material requirements and the process itself, rotomolding incurs a higher cost for production compared to other similar molding processes. This is also why rotomolded dehumidifiers are more expensive than models made from steel or other metals.

Important Features of a Rotomolded Dehumidifier

When choosing a portable industrial dehumidifier, it’s important to consider your budget and the specifications of each unit to find what matches your needs the best.

Moisture Extraction Rate

This refers to the total amount of water the dehumidifier can collect within 24 hours, typically measured in pints per day or PPD. There are two values often indicated by manufacturers, the rates under AHAM conditions and at saturation. The AHAM capacity is the amount collected at the average condition of 80°F and 60% RH, as recommended by the Association of Home Appliance Manufacturers. The maximum water removal capacity is the largest amount that it can extract per day at the ideal condition of 90°F and 90% RH. Most dehumidifiers are advertised with both capacities. 

Industrial dehumidifiers for water damage restoration typically come with at least a 70 PPD AHAM capacity, going up to 200 PPD and beyond. Look for Energy Star ratings to ensure you’re getting an energy efficient dehumidifier.

Coverage Area

Rotomold dehumidifiers are built specifically for large wet spaces in need of quick drying and dehumidification. Take note of the coverage area when choosing a dehumidifier. A standard unit can cover anywhere from 2,000 to 8,000 square feet. Another specification you must consider when sizing a dehumidifier is the airflow rate measured in cubic feet per minute (CFM) or cubic meters per hour (CMH). This is the volume of air the unit can process per unit of time. Industrial dehumidifiers also provide larger grain depression for a quicker and more efficient dehumidification.

Coverage Area


Industrial dehumidifiers are unsurprisingly large and heavy. For those in the business of water damage restoration or working on construction sites, you need a portable dehumidifier you can easily stack, store, and transport from site to site. Higher capacity typically comes in a bigger, heavier device. For easy movement and transportation, rotomold dehumidifiers are also designed with two large wheels and a sturdy handle.

Built-in Condensate Pump

These high-capacity dehumidifiers produce a lot of condensate in a single operation. Drainage can be a problem without a built-in pump. A pump allows you to operate the unit anywhere as long as the end of the drain hose can reach the sink, drain, or window where the water can be drained up to a certain height limit. 

Low-Temperature Operation

Some job sites like warehouses or storage areas can get extremely cold and dehumidifier compressors may have trouble running at low temperatures. To combat this, most industrial dehumidifiers are equipped with advanced defrosting systems to continue working in temperatures down to 36°F or lower.

Build Quality

Industrial dehumidifiers are built with a metal casing and heavy-duty rotomolding, as opposed to the lightweight plastic commonly found in residential dehumidifiers. This makes them more durable and more likely to survive in harsh environments. The manufacturer should also provide a good warranty to give the customer more confidence in the product’s quality. 

Additional Features

More advanced dehumidifiers may include etra features to make operation even more convenient for customers. This includes smart controls so you can monitor and adjust operation without going to the control panel. 


Rotomolding is the process of molding plastic used to create durable and flexible solid parts for industrial dehumidifiers and other equipment. These dehumidifiers are useful in water damage restoration and drying constructions and other large commercial spaces. Although the price cannot compare to residential dehumidifiers, the performance is well worth the money. If you need a dehumidifier for water damage emergencies but don’t want to buy one, contact your local hardware or appliance store to ask whether they’re renting out a dehumidifier.

Related Articles