For as many types and varieties of manufactured homes as are now
producedwith more to comethere are equally as many varieties
of installation and support systems. This is the first guide to
consider and compare the major foundation alternatives in use across
the country. This guide was developed to fill this void with two
goals in mind: to present a compilation of foundation ideas and
inventions culled from experts and practitioners across the nation;
and, to offer a range of practical and cost-competitive foundation
There is no single "best" foundation system. There is,
however, a way to organize the process of deciding among alternative
foundation designs that are appropriate for a given site and budget.
The process starts with recognizing and prioritizing the major factors
that influence the selection of the foundation system. Whether the
main considerations are initial cost, frost heave resistance or
a host of other issues, this information will help the reader focus
on an appropriate foundation design. Understanding the foundation
alternatives and proven design and installation practices is the
next step. By presenting both sets of information, this guide helps
narrow the field among many options and establish a methodical process
for decision making.
Purpose of the Guide
Users of this guide should find practical and helpful solutions
to their individual situations. Whether the reader is a retailer
trying to find better and more economical ways to deliver a finished
home, a contractor faced with an unusual soil condition, or anyone
wanting to better understand the alternatives, suggestions can be
found in this guide. There are summaries and tables for quickly
identifying appropriate foundation systems for a particular site
and homebuyer, as well as technical details for direct application
to the project at hand.
A Source of First Resort for Foundation Systems
The guide is intended to be instrumental in fostering the wider
dissemination of good ideas and "out of the box" thinking
that characterizes the manufactured housing industry in general.
use a combination of interior piers and perimeter walls to support
are recessed to create a "site-built" look.
Foundation Alternatives Rather
Than a Single Best Solution
Each system included in this compilation suggest advantages in at
least some settings. Comments about the pros and cons, as well as
the special limitations of each system, are included.
When deciding among alternatives, several key conditions and objectives
should be considered, such as: What is the budget? What kind of
financing will be sought? What type of soil is found at the site?
Is the area subject to frost? Is the home being placed in a land-lease
community or on private land? Is the area subject to high winds,
floods, or deep frost penetration? This guide explains how these
factors influence the selection and design of a foundation, and
makes suggestions and recommendations.
Information On All Types of Systems
The intent of this document is to be inclusive, offering guidance
on an array of foundation systems. However, since there are many
design variations, the guide only begins to sort through the options.
The guide also suggests a way of organizing foundation systems into
categories that are helpful in understanding almost any foundation
design. Often the home manufacturer's installation instructions
provide guidance on design and construction of foundation and support
systems. While this document is intended to complement the manufacturer's
guidelines, where there are discrepancies between the two documents
the manufacturer's instructions should be followed.
A Wide Range of Designs
Ideas and examples of foundation designs were solicited from all
parts of the manufactured housing industry. As a result, practitioners
willing to share their ideas suggested many very practical and proven
concepts. Experts, including licensed professional engineers and
contractors, reviewed each system that was submitted. Some designs
were eliminated because they were too specialized in their applicability.
The designs that are included are worthy of consideration for many
types of applications, sites and design objectives.
|There are numerous ways homes are actually
attached to their foundations.
HOW THE GUIDE IS ORGANIZED
The guide is organized into three sections as follows:
Factors to consider in foundation selection
This section discusses the major factors that drive the choice of
a foundation system and the issues that influence the specific design
of a foundation. The factors, listed below and discussed in detail,
are used to rate the relative merits of foundation designs:
- Site conditions
- Major design factors
- Best design practices
Non-proprietary systems, built
of readily available materials
This section covers four foundation classifications:
- Pier and ground anchor support systems (the most popular method
of securing manufactured homes to the ground)
- Crawl space systems
- Slabs-on-grade foundation systems
A non-proprietary system is considered to be "in
the public domain" usable by anyone without paying a
royalty, fee, or other consideration for its use. It is not a product
of manufacturing or individual company output. Non-proprietary systems
can be constructed by any qualified contractor, using materials
available from most building suppliers.
Included in each foundation class are a series of case studies drawn
from actual installations and contributed by practitioners from
across the nation. The case studies suggest how a basic concept
can be modified to meet the specific needs of a site, home design,
or buyer preference.
Proprietary systems, wholly-owned by a single
This section contains information about several proprietary foundation
products marketed to the manufactured housing industry. A proprietary
system is a product, manufactured by a company that owns some protectable
interest in the design. Some are patented. There is spirited competition
among manufacturers of these proprietary systems, resulting in rich
choices for the retailer, builder, contractor and homebuyer.
The information contained in this section was prepared by the companies
themselves. The following products and companies are represented:
- All Steel Foundation, Oliver Technologies, Inc.
- The Anchorpanel, Fast Track Foundation Systems
- Rigid Foundation Anchoring System, JM Products, Inc.
- The Storm Anchor System, The Anchor Post Company, LLC
- Vector Dynamics Foundation System, Tie Down Engineering
- Xi Foundation System, Tie Down Engineering