Steel Finish Selection
TIMBER TECH – Your Guide to Timber Frame Technology
Steel Finish Selection
Steel connections can be an important part of many timber systems. Steel is a strong material, capable of making connections that can resist very large loads. However, as strong as steel is, it has a critical weakness. It rusts. Rust deteriorates the steel causing it to become weaker. If rust is allowed to continue, the steel member can fail at its connections. There are ways to protect steel from rusting. Here are a few steel finishes that are most commonly used by Harmony Timberworks to make steel connections safer:
Hot Dipped Galvanized
Hot dipped galvanizing is when steel is dipped into a molten zinc bath. This creates a reaction which bonds a layer of zinc to the steel. Out of all the steel finishes that can be procured by Harmony Timberworks, hot dipped galvanizing creates the best possible steel protection, with the exception of the cost prohibitive stainless steel option. Add to this the fact that hot dipped galvanizing can be powder coated (at additional cost & turnaround time) and you can obtain an extremely durable product with the beauty of a colored finish.
► Lasts a very long time ► Cost effective
► Quick turnaround time ► Can be powder coated over
If cost were no matter, Stainless Steel is the best choice, with incredible resistance to deterioration. Due to the cost of material and to the added cost during the steel fabrication process, the cost of stainless can easily reach ten times that of carbon steel.
► Lasts a very long time ► Zinc Coating
► No build up on threads ► Can be powder coated over
► Quick turnaround time ► Choice of color
Zinc Coating is where a thin layer of zinc is applied to a steel member. This thin layer, although it does not penetrate, provides significantly more protection than no finish at all, but much less protection than that of hot dipping or powder coating. There is a positive to a thin zinc coating layer. Areas such as bolt threads will get built up too much during hot dipping or powder coating. This build up creates a big headache during assembly of your system. So, while Zinc coating is not typically the route taken for ultimate protection, using it for detail work in coordination with other finishes is typical. Zinc coating can be found in clear, black, and a limited number of other colors.
Powder coating is a process by which powdered paint is sprayed onto an electrostatic ally charged steel member then baked in an oven to create a rigid and uniform protective layer. Most of our clientele find that a powder coated finish is the most attractive. For steel applications that will be visible once a project is complete, powder coating is the recommended option. As long as surface abrasion is avoided, Powder coating is quite durable and requires little maintenance. Powder coating has slightly higher cost and turnaround time than that of hot dipped galvanizing, but is well worth it if aesthetics are of importance. Powder coating to a black or white finish is typical. Almost any color powder coating is available, but cost increases considerably to do so.
► Very attractive finish
► Choice of color
► Lasts a long time
Primed & Wet Painted
Priming and wet painting is a low cost, low durability alternative to the other above options. Paint can chip or crack over time, exposing vulnerable parts of the steel to humid weather and ultimately letting corrosion eat away at your structure. With regular maintenance, however, primed and painted steel is a feasible option.
► Not as expensive
► Quick turnaround time