Choosing Right Spa Component Materials: Balancing Performance, Cost, and Application
The material selection for spa components not only determines product performance but also influences user experience, brand reputation, and after-sales stability. Therefore, how to make scientific trade-offs based on component functions, usage environments, and target market positioning during material selection is a practical issue that every OEM client and system purchaser in the spa industry must address. This article will introduce several commonly used materials for spa components, presenting clear information through analogies and comparisons in combination with different application scenarios, to facilitate procurement decisions that balance performance, cost, and user experience.
Overview of Common Materials for Spa Components
The selection of materials for spa components is never an either/or choice between metals and non-metals, but rather a combinatorial decision that artfully pairs the two based on different usage scenarios and budgetary plans. The key to such combinations lies in a thorough understanding of the unique properties of various metallic and non-metallic materials — their respective standout advantages and unavoidable limitations. Only by doing so can each material be placed in its most suitable position to maximize its value.
Metal materials
Metal materials, with properties of sturdiness, heat resistance and corrosion resistance, play different roles in different application scenarios of spa components. Only by understanding the differences in properties, advantages and disadvantages of these commonly used metal materials can we achieve reasonable selection and optimal matching.
Stainless Steel
Stainless steel is an iron-based alloy that enhances corrosion resistance and mechanical properties by adding chromium (Cr) and nickel (Ni). 304 stainless steel and 316 stainless steel are the two most commonly used in industry, among which 316 stainless steel has stronger chlorine corrosion resistance due to containing molybdenum.
Pros: corrosion resistance, high humidity resistance, antibacterial property, high strength, beautiful appearance, easy to clean.
Cons: heavy weight, difficult processing, high cost.
Applicable components: inner and outer shells of sprinklers, supporting structures, overflow ports, drain covers, metal handles.
Aluminum Alloy
Aluminum alloy is a lightweight structural material mainly composed of aluminum, mixed with small amounts of metals such as magnesium and silicon. Due to its light weight, high thermal conductivity, and flexible surface treatment methods, aluminum alloy is often used in structural decorations like thermal cover brackets. It can not only reduce the overall weight of the equipment but also has good visual ductility. Its oxidation treatment can provide a variety of color options to meet OEM appearance customization needs.
Pros: Lightweight, easy to install; (excellent heat dissipation)
Cons: Low strength, not suitable for high-pressure environments; prone to scratches, requiring additional protective coatings
Applicable components: Thermal cover brackets
Non-metallic Materials
In the field of SPA components, non-metallic materials, with their unique chemical stability, plasticity, and lightweight properties, also demonstrate significant advantages in cost control and design aesthetics, thus occupying an important position in the production of housings, connectors, and comfort components.
ABS
ABS is one of the most commonly used engineering plastics. It is tough, lightweight, and easy to process, and is widely used in non-pressure-bearing parts such as sprinkler housings and control buttons. Its surface is suitable for electroplating and painting treatments, making it the preferred appearance material for standard spa products.
Pros: Low cost, fast molding speed; excellent impact resistance, lightweight and easy to process; electroplatable, paintable, and highly aesthetic.
Cons: Average temperature resistance (≤80°C); prone to aging and yellowing under long-term UV exposure.
Applicable components: spa jet cover, spa drainer cover, spa steps, spa filter
PVC
PVC is a widely used plastic material that can be modified with plasticizers to adjust its hardness, resulting in both rigid and flexible forms. In spa fittings, rigid PVC is widely used. With excellent corrosion resistance and sealing capability, it is extensively applied in the piping sections of spa systems.
PVC is a widely used plastic material – this also makes it one of the most common materials in spa plumbing systems, hot tub water pipes, and whirlpool air hose connections.
Pros: excellent chemical and corrosion resistance; low cost and lightweight; multiple connection methods, suitable for water route connections and sealing structures
Cons: not suitable for withstanding high impact or pressure; relatively brittle
Applicable Components: water pipes, air pipes, drainage systems, air hose connectors, joint sealing structures
PP
Compared with PVC, PP offers better heat resistance, higher toughness, and lower density. Its non-hygroscopic nature and lightweight properties make it a preferred material for many spa components requiring reduced weight. It is commonly used in S-shaped drain traps, water seal assemblies, and certain antibacterial parts. In addition, PP features excellent chemical stability, making it resistant to aging and cracking even after long-term use.
Pros: heat and alkali resistance; low density, non-hygroscopic; good stress cracking resistance
Cons: lower toughness and impact resistance; limited surface treatment options
Applicable Components: S-shaped drain traps, water seal assemblies; sanitary connectors, antibacterial filtration components
PC
PC is a high-transparency, impact-resistant engineering plastic. It can withstand minor impacts while maintaining excellent light transmittance, making it commonly used for LED light covers, transparent inspection windows, and control panels.
Pros: high transparency; excellent impact resistance; heat-resistant and flame-retardant
Cons: prone to scratching, protective coating required; relatively high cost
Applicable Components: LED light covers, control panels, transparent viewing windows
PS
PS is a thermoplastic material with high rigidity and easy moldability, suitable for non-pressure-bearing decorative structures.
Pros: precise molding with high surface gloss; low cost
Cons: high brittleness and poor impact resistance; limited heat resistance
Applicable Components: PS panels
PU
PU is a polymer material with a soft touch, ideal for components that come into frequent contact with the human body. With strong cushioning, compression resistance, and abrasion resistance, it is one of the key materials for enhancing user comfort.
Pros: soft and elastic; pressure-resistant and wear-resistant with skin-friendly texture; moldable into complex shapes
Cons: poor heat resistance, may soften in hot water over time; moderately high cost
Applicable Components: headrests, massage backrests, edge trims; premium cushions and wrapped components
Spa Component Material Comparison: Durability, Heat Resistance, and Cost
Material | Corrosion Resistance | Heat Resistance | Lifespan | Cost Level |
Stainless Steel | Very High | ≥ 200°C | ★★★★★ | High |
Brass | High | ≥ 150°C | ★★★★ | High |
Aluminum Alloy | Medium | ≤ 130°C | ★★★ | Medium |
Zinc Alloy | Medium | ≤ 120°C | ★★★ | Medium-Low |
ABS | Medium | ≤ 80°C | ★★★ | Low |
PVC | High | ≤ 60°C | ★★★★ | Very Low |
| PP | Medium-High | ≤ 100°C | ★★★★ | Low |
| PC | Medium | ≤ 110°C | ★★★★ | Medium |
| PS | Medium | ≤ 90°C | ★★★ | Low |
| PU | Medium | ≤ 80°C | ★★★★ | Medium-High |
Material Performance and System Matching in Spa Components
Different materials exhibit different functional properties when used in various spa system environments. These differences are closely related not only to the material itself, but also to the spa system's structure and medium conditions. Therefore, when selecting materials, buyers should not only focus on the inherent performance of the material, but more importantly, its ''environmental adaptability''.
Spa Massage System: Requires Good Airtightness
System characteristics: powered by an air blower, air is injected through jets to create a bubbling massage effect
Operational requirements: the entire air circuit must be highly sealed to prevent leakage, pressure loss, or uneven bubble distribution
Typical components: air jets, air valves, check valves, air hose connectors
Recommended materials: ABS, PP, PVC
Matching logic: ABS offers high molding precision, suitable for valve bodies and control surfaces; PP is lightweight and fatigue-resistant, ideal for moving parts like check valves; PVC provides flexible pipe connections to improve system airtightness
If materials are improper: weak bubbling, poor massage effect, excessive blower load
Spa Circulation System: Requires High Pressure Resistance
System characteristics: provides stable water flow, maintains temperature balance and water filtration
Operational requirements: long-term operation under pressure, corrosion resistance and structural strength are key indicators
Typical components: circulation pumps, filter connectors, suction/discharge fittings, water piping
Recommended materials: PVC, ABS, stainless steel
Matching logic: PVC piping is pressure- and corrosion-resistant, suitable for medium-pressure operation; ABS offers higher mechanical strength, used for load-bearing components; brass/stainless steel ensures durability in high-pressure or corrosive conditions
If materials are improper: pipe rupture, pump leakage, interface aging and water seepage
Spa Thermostatic System: Requires High Heat Resistance
System characteristics: heats the water to a comfortable temperature (typically 35–42°C) and maintains it steadily
Operational requirements: must withstand long-term high temperatures without deformation or aging, and provide efficient heat transfer
Typical components: heater casing, temperature probe housing, connector nuts
Recommended materials: stainless steel, PC
Matching logic: stainless steel casings conduct heat efficiently and resist corrosion, ideal for high-humidity environments; PC engineering plastics provide excellent heat resistance to ensure connectors and housings remain intact
If materials are improper: decreased heating efficiency over time, deformation or cracking of plastic parts
Spa Lighting System: Requires High Light Transmittance
System characteristics: creates ambiance and enhances user experience, a key design element in premium spas
Operational requirements: light covers must be highly transparent, color-stable, and able to withstand some heat
Typical components: LED light covers, transparent control windows, light guide rings
Recommended materials: PC, stainless steel
Matching logic: PC offers high transparency and impact resistance, ideal for LED covers; stainless steel enhances visual appeal and assists with sealing and installation
If materials are improper: yellowing lights, cracked covers, uneven lighting
Spa Comfort System: Requires Skin-friendly Materials
System characteristics: directly contacts the human body, enhancing comfort and relaxation during bathing
Operational requirements: materials must be soft, non-toxic, skin-friendly, and resistant to hot water corrosion or deformation
Typical components: headrests, backrests, cushions, armrest trim
Recommended materials: PU
Matching logic: PU provides superior softness and cushioning, ideal for premium spa products
If materials are improper: uncomfortable touch, surface peeling, hardening and cracking
Spa Control System: Requires Scratch-resistant Materials
System characteristics: responsible for user interaction, status display, and system adjustment – the core interface for users
Operational requirements: control panels must resist scratching, water, and corrosion to maintain visual clarity and tactile performance
Typical components: button panels, control windows, touch-sensitive covers
Recommended materials: PC, ABS, laminated TPU
Matching logic: PC is durable and transparent, used for viewing windows and glossy panels; ABS allows flexible surface treatments for various textures and colors; TPU film enhances scratch resistance and waterproofing, especially in touch areas
If materials are improper: blurry display, accumulated scratches, button malfunction
Matching Materials to Spa System Structures and Applications
High-Temperature vs. Low-Temperature Environments
High-temperature scenarios (above 40°C): Avoid materials with poor thermal stability such as PVC and PS. Recommended options include PP, PC, and stainless steel.
Low-temperature or cold regions: Use materials with strong impact resistance to prevent cracking, such as PU and PP.
Outdoor vs. Indoor Installations
Outdoor spa systems: Materials must be UV-resistant, weatherproof, and anti-aging. Recommended materials include PC, stainless steel, and weather-grade ABS.
Indoor spa systems: More decorative and cost-effective materials may be used, such as aluminum alloy and standard ABS.
Water Contact vs. Human Contact Components
Water-contact parts (e.g., jets, drains): Require corrosion resistance and scale prevention. Suitable materials include stainless steel, PVC, and brass.
Human-contact parts (e.g., headrests, buttons): Must be soft, skin-friendly, and preferably antibacterial. PU and food-grade ABS are ideal options.
Residential vs. Commercial Spa Systems
Commercial spa systems: Designed for frequent use; materials should be highly durable and pressure-resistant. Recommended choices include 316 stainless steel, brass, and PC.
Residential spa systems: Materials can be more budget-friendly while still meeting performance needs. Common selections include ABS and PVC.
Hydrorelax's Material Strategy and Quality Commitments
Material selection not only determines product performance but also significantly impacts user experience, brand reputation, and after-sales stability.
At Hydrorelax, scientific material selection is regarded as an integral part of a system-level solution. Leveraging years of engineering expertise and material knowledge, we provide OEM customers, project developers, and brand buyers with practical, implementable material recommendations. Our support covers the entire value chain—from design and material selection to mass production and delivery.
Moreover, all Hydrorelax product materials comply with European REACH and RoHS standards. For export markets—especially Europe—we use non-toxic, lead-free, and recyclable raw material systems to ensure both environmental protection and user safety.
Our Commitments:
1.Rigorous Material Evaluation System: raw material inspection, batch traceability, and multiple rounds of testing
2.Customized Recommendations: material selection tailored to the customer’s specific system requirements
3.Compatibility: ensuring seamless integration with internationally recognized brand fittings and jets
4.Optional Environmentally Friendly, Flame-Retardant, and Antibacterial Materials
We welcome your inquiries at any time and are ready to present you with spa component solutions backed by over 20 years of experience.