Pool Pump Housing: Thermoplastic vs Composite Materials

Housing material as a listing word

Pool pump titles and bullet lists sometimes name the material of the pump body. On this site, thermoplastic and composite are read as listing words: they tell you what the housing is made from, not how that material performs. A listing that does not name a material is listed as "material not stated by the seller."

The housing is the outer body of the pump that holds the volute, the impeller area and the strainer housing. When a title says the pump has a thermoplastic housing or a composite housing, it is naming the material used for that body. The word appears beside other stated details such as the horsepower, the speed type and the pool type.

The material word does not carry a set of requirements. A pump named for thermoplastic is not automatically an above ground pump, and a pump named for composite is not automatically an inground pump. The pool type is a separate stated detail in the listing, and it may appear even when the material does not. Reading the housing material explains how the material word fits with the rest of the listing.

Thermoplastic as a listing term

Thermoplastic is a type of plastic that softens when heated and hardens when cooled, which allows it to be molded into shapes. In a pump listing, the word tells you the housing is plastic rather than metal. Above ground pump listings, including those with model lines sold under the Intex and Bestway names, often name a plastic housing, and the word commonly appears in the bullet list rather than in the title line.

A title may say "thermoplastic housing" or "corrosion-resistant thermoplastic." The first phrase names the material. The second adds a claim that the listing states. This site repeats a stated claim when it is part of the listing text, but does not compare one material against another and does not treat a stated claim as a measured result.

If a listing states the housing material, the material is one of several stated details. The other stated details, such as horsepower, speed type and voltage, do the same work in the listing as the material word. A pump with a thermoplastic housing may be a single speed, dual speed or variable speed model; the speed type is read from the same title.

Composite as a listing term

Composite describes a material made from two or more constituent materials. In pool pump listings, the word usually names a reinforced plastic, sometimes with fiberglass or another reinforcement. Inground pump model lines, including those sold by Hayward and Pentair, may use the word composite for the housing, the diffuser, the impeller or the strainer body.

As a listing word, composite has the same job as thermoplastic: it names the material. The listing does not state measured results for the material, so the site cannot compare composite against thermoplastic for durability, corrosion resistance or weight. The reader should read the word as a stated material and move on to the details that affect pump choice, such as horsepower, flow figures and pool type.

A listing may use both words in one entry, naming a thermoplastic body with a composite impeller or another combination. Each word names a separate part. Reading the full title and the bullet list tells you which part each word names.

Inground and above ground housing words

The pool type often appears beside the material word. An above ground pump title may name a thermoplastic housing because an above ground pump sits above grade and the housing is visible. An inground pump title may name a composite or reinforced housing. These are listing words, not a set of rules.

When one pump model is listed for both inground and above ground pools, the title usually says "for inground and above ground pools." The material word, if present, applies to both. If the listing does not state the pool type, the site lists it as "pool type not stated by the seller."

The material word does not determine whether the pump is an above ground or inground model. The pump's fittings, horsepower and voltage do more of that work in the listing. Read the material for what it names, then read the pool type and the horsepower for the pump's application.

A related detail is the motor enclosure. Some pump listings name a totally enclosed fan-cooled (TEFC) motor or an open drip-proof (ODP) motor; reading the motor enclosure words explains what those words name. The housing material and the motor enclosure are separate stated details, and both can appear in the same title.

What a listing does not tell you

A housing material word does not tell you which material lasts longer, resists corrosion better in salt water, or weighs less. Those are measured material properties, and the catalogue listings on this site do not state measurements for them. The site compares stated details only: the material word, the pool type, the speed type, the horsepower and the flow figures.

The phrase "corrosion resistant" may appear in a listing as a stated feature. The site reads it as the seller's stated words. It is not a measured claim the site can verify, and it is not a promise of performance in a salt water pool. For a salt water pool, the maker's specifications are the place to check the housing material.

Weight is a stated figure in some listings. When a listing states a weight figure, the site reads the figure as stated. The site does not compare weight as a performance measure between two pumps, because weight alone does not tell you how the housing performs.

For the same reason, the site cannot compare durability between thermoplastic and composite. Durability is a measured material property. The listing words name the material, and the maker's manual describes how the housing is designed and how to care for it. The maximum ambient temperature is one of the details the manual may state.

Questions for the maker

The maker's manual and the maker's sizing page state what the housing material is designed for and how to care for it. Before choosing between a pump named for thermoplastic and one named for composite, ask the maker:

• Is the housing intended for the pool type in the listing, inground or above ground?
• Does the manual state a maximum ambient temperature for the housing?
• Does the maker state whether the housing is intended for salt water?
• What does the warranty cover for the housing, and for how long?
• Does the maker publish a sizing page or performance curve for the pump model?

What to pick for your situation

Questions

What does thermoplastic mean in a pool pump listing?

Thermoplastic is a plastic that softens when heated and hardens when cooled, so it can be molded into the shape of a pump housing. In a listing, the word names the material of the housing or another part. The site reads it as a stated material, not as a performance claim.

What does composite mean in a pool pump listing?

Composite names a material made from two or more constituent materials. In pump listings it usually means a reinforced plastic, sometimes with fiberglass. The word names the part it describes, such as the housing, the impeller or the diffuser.

Is composite more durable than thermoplastic?

This site does not compare durability between the two materials. Durability is a measured material property that the listings do not state. The correct reading is to treat each word as a stated material and to ask the maker about the housing's design and warranty.

Does the housing material tell you if a pump works for an above ground pool?

No. The pool type is a separate stated detail in the listing. An above ground pump may name a thermoplastic housing, and an inground pump may name a composite housing, but the pool type is read from its own line in the title.

What should you do if a listing does not name the housing material?

Read the listing as "material not stated by the seller" and shop on the details the listing does state, such as horsepower, speed type, voltage and pool type. The maker's manual or product page can answer a material question if the listing does not.