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Using Light Gauge Steel
Framing for Manufactured Homes
The use of light
gauge steel in the structural system of residential construction has taken hold
in some site building markets but potentially offers far more value to the manufactured
home industry. The Manufactured Housing Research Alliance (SBRA) is coordinating
an effort to develop a market competitive structural design, based on light gauge
structural steel technology and suitable for the home manufacturing environment.
This report summarizes findings of the first phases of the research. The effort
is a cooperative undertaking of SBRA, the Manufactured Housing Institute (MHI),
several home manufacturers, the North American Steel Framing Alliance (NAFSA)
and the US Department of Housing and Urban Development (HUD).
is a wood framed based industry. The HUD code industry has grown up around wood
framing technology and significant time and expense has been invested in value
engineering wood as the structural material of choice. The manufacturing process
is based on lumber dimensions, material assembly methods and other building materials
are selected to be used in conjunction with wood products. However, relative to
wood, light gauge steel possesses a compelling set of material properties. Steel
is lightweight, fireproof, vermin resistant, dimensionally stable (not subject
to material decay, warping and twisting and shrinkage) and can be fabricated to
a wide range of shapes and sizes with virtually no material wastage.
are additional factors that suggest the industry would be well advised to consider
options to wood as the basic structural building block. Foremost among these are
the uncertainties associated with future wood resources and the historic price
fluctuations that at times have made wood more expensive than steel. Even if steel
proved to be less attractive than wood in the short term, as a future alternative
material, steel shows considerable promise.
This phase of the research
was shaped by the following two overriding objectives:
that it is possible to produce a light gauge steel framed home at about the same
or at a lower first cost than a comparable wood framed system
that such a design can comply with the Federal Manufactured Home Construction
and Safety Standards.
In a process that spanned
several years, the project team evolved a steel frame design that satisfied both
objectives. The major product of this study is a design for a prototype home,
documented in this report, consisting of a structural frame made entirely of light
gauge steel components, that is cost competitive with a comparable wood frame
design. The design has been reviewed by a DAPIA and deemed to be in compliance
with the Federal Manufactured Home Construction and Safety Standards (FMHCSS).
This research covers important ground but leaves unanswered important questions
about the economic and technical viability of steel frame. Additional study is
needed to more completely make the case for replacing wood with steel, and this
work took the necessary first steps in moving the technology forward.