Steel framing has been used for many years in commercial construction projects. Designers of schools, shopping centers, and hospitals often specify it. But steel framing may at first seem an unusual building material for houses even though homeowners living in steel-framed houses don’t often realize that the frame is steel rather than wood. This is because the finished house doesn’t look any different than any other house. Despite several decades of use, the average residential builder may be only vaguely familiar with steel framing. While it isn’t found at every building supply store, most large cities have one or more distributors.
When most people hear me mention steel framing, they often envision the heavy steel I-beams used in skyscrapers. Such material is entirely too heavy for most residential applications. The material that is appropriate for residential construction is called light-weight steel framing. It actually weighs less than wood framing and is made from galvanized (zinc-plated) sheet metal, so it is rust-resistant. Some insurance companies offer a discount on steel-framed houses because the framing is fireproof.
Steel studs are C-shaped in cross section and are manufactured in a wide variety of sizes. They have holes pre-punched in them for electrical wiring and plumbing lines and they fit into U-shaped channels (also called tracks or runners) at the top and bottom of a wall. The larger sizes are used for rafters and joists. Light-weight steel framing can be used to replace wood framing in nearly all applications. Roof trusses can easily be made up using smaller steel studs. They look very similar to their wood counterparts and standard designs are available from steel stud manufacturers.
Light-weight steel framing is available in two general types: load-bearing and non-load-bearing. Load-bearing studs help support the roof, non-load-bearing studs do not. Load-bearing studs are made of thicker sheet metal and are meant to support the weight of the house. Non-load-bearing studs, made of thinner material, can be used for interior partition walls. They only need to support themselves and the weight of the wall covering material.
A thin oil film sometimes adheres to steel studs following the manufacturing process. On occasion, I have gone to the trouble of washing the oil off with TSP, a heavy duty cleaner available from hardware stores. However, I have found that if the studs are exposed to the rain and sun, the oil will tend to evaporate and wash away. Many suppliers store steel framing outdoors, so it often arrives on the job already oil-free. If the studs do have any residual oil on them, it can be washed off by hand, but I have found that it dissipates fairly quickly during construction, so the studs are usually oil-free by the time the house is closed up. If you do decide to wash the studs, keep in mind that if a house is constructed in an airtight manner, then the studs within the insulated walls will be well-separated from the living space, so it will only be necessary to wash the studs that sensitive occupants could be exposed to—those within uninsulated interior partition walls.
In many ways, a steel-framed house is very similar to a wood-framed house. Both have vertical studs, horizontal members at the top and bottom of walls, wind bracing at corners, and so on. There are some differences, the biggest of which is that self-tapping screws are used in steel framing, as opposed to nails in wood framing. A few different tools are also required when working with steel. Once builders overcome their initial apprehension, it is relatively easy to learn how to work with light-weight steel framing.
(This article is from the archives of the original Healthy House Institute, and the information was believed accurate at the time of writing.)
(Note: The views expressed in this article are those of the author, and do not necessarily represent those of The Healthy House Institute, LLC.)
