Can I use 304 stainless steel screws for a coastal deck, or do I need 316?

The difference between the two grades is because of one chemical element: Molybdenum.

Grade 304: This has chromium and nickel which makes it very good at resisting corrosion in places that are not near the ocean. It is the stainless steel that people use in kitchens and outdoors away from the sea.

Grade 316: This has about 2% to 3% molybdenum. This makes it much better at resisting salt, which's in sea spray and coastal fog.

Fasto will do a test to make sure the stainless steel screws are quality especially when it comes to salt.

People who have been in the industry for a time usually follow a simple rule. If your project is within five miles of the ocean you should use Grade 316 steel.

Marcus Thorne, a consultant who specializes in buildings near the ocean says "We see it every year. A homeowner tries to save money by using Grade 304 steel.. By the second winter the screws are already rusting and making a mess on the deck."

This year many people are using Bimetal Screws, the Grade 316 kind. These screws have a tip made of carbon steel and a body made of Grade 316 stainless steel. This makes it easy to screw into wood or metal without the screw breaking.. It still resists salt, which is important for buildings near the ocean.

Fasto is a manufacturer of bimetal screws in China and has the necessary certificates like CE and SGS.

If you are near the ocean you should use Grade 316 steel. If you are not near the ocean and it is not humid Grade 304 is still a good choice.

Before you start building you should check the building codes. Many places near the ocean now require Grade 316 steel, for all outdoor structures.

We make high-quality fasteners that can be customized for projects.

Contact us for high quality bimetal screws→.