Strut channel
Encyclopedia
Strut channel, often referred to colloquially by one of several manufacturer trade names (e.g. "Kindorf", "Unistrut", "SuperStrut", "Strut", "Metstrut"), is a standardized formed galvanized steel (or sometimes aluminium
) structural system used in the construction and electrical industries for light structural support, often for supporting wiring, plumbing, or mechanical components such as air conditioning or ventilation systems.
Strut is formed from metal sheet, folded over into an open channel shape with inwards-curving lips to provide additional stiffness and as a location to mount interconnecting components. Strut usually has holes of some sort in the base, to facilitate interconnection or fastening strut to underlying building structures.
The main advantage of strut channel in construction is that there are many options available for rapidly and easily connecting lengths together and other items to the strut channel, using various specialized strut-specific fastener
s and bolts
. It can be assembled very rapidly with minimal tools and only moderately trained labor, which reduces costs significantly in many applications. A strut channel installation also can often be modified or added-to relatively easily if needed. The only alternative to strut channel for most applications is custom fabrication using steel bar stock and other commodity components, requiring welding and/or extensive drilling and bolting, which has none of the above advantages.
In US units, the basic typical strut channel forms a box 1 5/8 inch by 1 5/8 inch. In metric units, this is a 41 mm by 41 mm unit. There are several additional sizes and combined shapes manufactured.
The material used to form the channel is typically 12 gauge (0.1046 inch) or 14 gauge (0.0747 inch) thick sheet metal.
Several variations are available with different hole patterns for mounting to walls and supports. Solid channel has no holes predrilled, and must either be drilled on site or mounted in another fashion. Punched channel has round holes, large enough for 5/8 inch threaded steel rod or bolts, punched in the top of the channel at regular 1 7/8 inch centers. Half-slot channel has short, rounded end rectangular slots punched out on 2 inch centers. Slot channel has longer slots on 4 inch centers.
In addition, shapes are manufactured with two lengths of channel welded together back to back, or three or four welded together in various patterns, to form stronger structural elements.
, with a zinc coating (galvanized), paint
, epoxy
, powder coat, or other finish.
Strut channel is also manufactured from stainless steel
for use where rusting might become a problem (eg., outdoors, facilities with corrosive materials), and from aluminium alloy
when weight is an issue.
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
) structural system used in the construction and electrical industries for light structural support, often for supporting wiring, plumbing, or mechanical components such as air conditioning or ventilation systems.
Strut is formed from metal sheet, folded over into an open channel shape with inwards-curving lips to provide additional stiffness and as a location to mount interconnecting components. Strut usually has holes of some sort in the base, to facilitate interconnection or fastening strut to underlying building structures.
The main advantage of strut channel in construction is that there are many options available for rapidly and easily connecting lengths together and other items to the strut channel, using various specialized strut-specific fastener
Fastener
A fastener is a hardware device that mechanically joins or affixes two or more objects together.Fasteners can also be used to close a container such as a bag, a box, or an envelope; or they may involve keeping together the sides of an opening of flexible material, attaching a lid to a container,...
s and bolts
Screw
A screw, or bolt, is a type of fastener characterized by a helical ridge, known as an external thread or just thread, wrapped around a cylinder. Some screw threads are designed to mate with a complementary thread, known as an internal thread, often in the form of a nut or an object that has the...
. It can be assembled very rapidly with minimal tools and only moderately trained labor, which reduces costs significantly in many applications. A strut channel installation also can often be modified or added-to relatively easily if needed. The only alternative to strut channel for most applications is custom fabrication using steel bar stock and other commodity components, requiring welding and/or extensive drilling and bolting, which has none of the above advantages.
In US units, the basic typical strut channel forms a box 1 5/8 inch by 1 5/8 inch. In metric units, this is a 41 mm by 41 mm unit. There are several additional sizes and combined shapes manufactured.
Shapes
Basic strut channel comes in the open box section, 1 5/8 by 1 5/8 inch square cross section. A half height (1 5/8 inch wide, 13/16 inch tall) cross section version is also available, used mostly where mounted directly to a wall as it has significantly less stiffness and ability to carry loads across an open space or brace. A deep channel 2 7/16 inches tall and 1 5/8 inch wide is also manufactured.The material used to form the channel is typically 12 gauge (0.1046 inch) or 14 gauge (0.0747 inch) thick sheet metal.
Several variations are available with different hole patterns for mounting to walls and supports. Solid channel has no holes predrilled, and must either be drilled on site or mounted in another fashion. Punched channel has round holes, large enough for 5/8 inch threaded steel rod or bolts, punched in the top of the channel at regular 1 7/8 inch centers. Half-slot channel has short, rounded end rectangular slots punched out on 2 inch centers. Slot channel has longer slots on 4 inch centers.
In addition, shapes are manufactured with two lengths of channel welded together back to back, or three or four welded together in various patterns, to form stronger structural elements.
Materials
Strut is normally made of sheet steelSteel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
, with a zinc coating (galvanized), paint
Paint
Paint is any liquid, liquefiable, or mastic composition which after application to a substrate in a thin layer is converted to an opaque solid film. One may also consider the digital mimicry thereof...
, epoxy
Epoxy
Epoxy, also known as polyepoxide, is a thermosetting polymer formed from reaction of an epoxide "resin" with polyamine "hardener". Epoxy has a wide range of applications, including fiber-reinforced plastic materials and general purpose adhesives....
, powder coat, or other finish.
Strut channel is also manufactured from stainless steel
Stainless steel
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....
for use where rusting might become a problem (eg., outdoors, facilities with corrosive materials), and from aluminium alloy
Aluminium alloy
Aluminium alloys are alloys in which aluminium is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories...
when weight is an issue.