Why Choose Marine Grade Washers?
Marine grade washers are used with bolts, screws, nuts, threaded rod and other fasteners in applications exposed to moisture, weather, salt air or demanding outdoor conditions. They are commonly selected for docks, decks, railings, brackets, equipment, trailers, signs, panels and coastal maintenance work.
For marine and coastal environments, stainless steel and silicon bronze washers are often chosen because they offer better corrosion resistance than many plain steel or zinc plated options. The correct washer style, material, diameter and thickness should be matched to the fastener, mating surface and exposure level before installation.
Choosing the Right Marine Grade Washer
The right washer depends on the fastener size, surface material, load requirements and purpose of the washer. Flat washers, fender washers, lock washers, square washers, cup washers and sealing washers are designed for different uses, so compare the washer style and dimensions before ordering.
Flat Washers
Flat washers provide a bearing surface under a bolt head, screw head or nut. They help spread load over a wider area and can be used as spacers in compatible assemblies. For outdoor or marine-related use, match the washer material to the bolt, screw or nut being used.
Fender Washers
Fender washers have a larger outside diameter compared to many standard flat washers. They are useful where more bearing surface is needed, especially over thinner materials, larger holes or softer surfaces. Stainless steel fender washers are commonly selected for outdoor panels, brackets, repairs and hardware assemblies.
Lock Washers and Tooth Washers
Lock washers and tooth washers are used in assemblies where added resistance to loosening may be desired. Split ring lock washers, internal tooth washers and external tooth washers each interact with the mating surface differently. Confirm the washer style, material and application suitability before use.
Silicon Bronze Washers
Silicon bronze washers are commonly selected for marine-related assemblies, boat building, dock work, coastal hardware, wood construction and applications where bronze fasteners or compatible copper-based hardware are being used. They are often chosen where corrosion resistance and material compatibility with silicon bronze fasteners matter.
Sealing and Cushioning Washers
Sealing and cushioning washers are designed to add a sealing or cushioning layer between the fastener and the surface. They may be used with compatible screws, panels, sheet metal or outdoor assemblies where moisture intrusion or vibration may be a concern. They are not a substitute for full waterproofing when the application requires a dedicated sealant, gasket or engineered sealing system.
Marine Grade Material Considerations
316 stainless steel is commonly selected for marine, coastal and chloride-exposed environments because it offers stronger corrosion resistance than many general-purpose stainless grades. 18-8, 304 and A2 stainless steel may be suitable for many outdoor and moisture-prone uses, but harsher salt air, dock or waterfront exposure often requires closer material review.
Silicon bronze is another common material option for marine grade washer applications. It is often used with silicon bronze bolts, screws, nuts and other compatible bronze hardware in wet, coastal and marine-related environments. When appearance, material compatibility or copper-based hardware matters, silicon bronze may be the better match than stainless steel.
Stainless steel and silicon bronze should not be treated as interchangeable in every application. The best washer material depends on the mating fastener, surrounding hardware, exposure level, appearance needs and material compatibility. Stainless steel and silicon bronze both offer corrosion resistance, but neither material is rust proof or corrosion proof in every environment.
Installation and Compatibility Considerations
Before ordering marine grade washers, confirm the inside diameter, outside diameter, thickness, washer style and material. The washer inside diameter should fit the fastener properly, while the outside diameter should provide the bearing surface needed for the application.
For wet, coastal or marine-related environments, avoid mixing incompatible metals without checking material compatibility. The full assembly should be reviewed, including the washer, mating fastener, nut, bracket, base material and any nearby metals.
Related Marine Grade and Washer Categories
Browse related marine grade and washer categories to compare washer styles, materials and application options.
- Marine Grade Fasteners
- Stainless Steel Washers
- 316 Stainless Steel Flat Washers
- 316 Stainless Steel Fender Washers
- 316 Stainless Steel Lock Washers
- 316 Stainless Steel Sealing and Cushioning Washers
- 316 Stainless Steel Square Washers
- 316 Stainless Steel Finishing Cup Washers
- Silicon Bronze Washers
- Silicon Bronze Flat Washers
- Silicon Bronze Lock Washers
- Silicon Bronze Finishing Cup Washers
Marine Grade Washers FAQs
What are marine grade washers used for?
Marine grade washers are used with bolts, screws, nuts, anchors and threaded rod in outdoor, coastal, dock, deck, marine and moisture-prone assemblies where corrosion resistance and proper bearing surface are important.
Are marine grade washers always 316 stainless steel?
Not always. Marine grade washers may include 316 stainless steel, A4 stainless steel, 18-8 stainless steel, 304 stainless steel, silicon bronze or another corrosion-resistant material depending on the product listing. Confirm the listed material before purchasing.
When should I use silicon bronze washers?
Silicon bronze washers are commonly used with silicon bronze fasteners, bronze hardware, boat building projects, dock work, coastal applications and other assemblies where copper-based material compatibility matters.
What washer type should I use for a larger bearing surface?
Fender washers are commonly selected when a larger outside diameter and wider bearing surface are needed. They can be useful over larger holes, thinner material or softer mating surfaces.
Are sealing washers waterproof?
Sealing washers can help add a sealing or cushioning layer in compatible assemblies, but they should not be treated as a full waterproofing system. Use the proper sealant, gasket or engineered sealing method when the application requires it.
What should I check before buying marine grade washers?
Check the washer style, material, stainless grade or bronze material, inside diameter, outside diameter, thickness, package quantity, mating fastener size and whether the washer is suitable for the project environment.