Permanent foundations must be built of durable materials; that is,. Concrete, masonry with mortar or treated wood, and built on site. You must have attachment points to anchor and stabilize the prefabricated house to transfer all loads, defined in this document, to the underlying soil or rock. Choosing whether or not you want a permanent or non-permanent foundation is another important element to consider when choosing the foundation for your prefabricated or modular home.
Permanent foundations do not have the capacity to be moved to another location and allow you to place your home on them permanently. These foundations make it much easier for your modular or prefabricated home to be viewed as “real property” in terms of financing. Permanent foundations include the basement, the mezzanine and the slab with foundations that border blocks. The saddest question I often hear in my engineering inspection practice is: Buck, I need an engineering inspection of the foundation of a manufactured home to get an FHA loan.
The mortgage insurer wants to ensure that the foundation meets its permanent foundation guidelines. Can you do this and what is the cost? Why is this? Well, it's because the foundation underneath the house was never designed according to the initial guidelines. And this is sad, because an FHA Permanent Foundation would probably ensure that the prefabricated house would survive the worst electrical storms and strong straight-line winds and perhaps even some lower-category hurricanes, or that it would never settle or sink to the ground unevenly. Size of the base to avoid overloading the bearing capacity of the soil and to prevent soil settling.
The base must be made of reinforced concrete to be considered permanent. Base of the base below the maximum depth of frost penetration. It encloses a basement with reduced space with a continuous wall (with or without support) that separates the basement from the small space of the landfill and prevents vermin and water from entering. Unlike conventional wood-framed housing, prefabricated houses are extremely lightweight.
While the dead weight of a conventional home often prevents the house from rising or sliding on the foundation, prefabricated houses can easily be lifted, slipped, or overturned on poor foundations. That's why we often hear meteorologists on television warning residents of prefabricated houses to leave their homes and head to safety whenever a windstorm is coming. In an FHA permanent foundation system, the combined weights of the buried concrete foundations and the components that are above the foot are designed to keep the house firm at the design wind speed established by local building codes. Therefore, every time a real estate agent calls me to carry out an inspection of this type, I always tell them about my experiences and explain that a minimum fee will have to be paid for my inspection.
If I believe that the foundation can meet the FHA guidelines, I will take the necessary steps and collect the necessary data during the inspection, then return to the office and make the necessary calculations so that, hopefully, I can write a positive report. In this case, the cost of my services will be substantially higher because of all this extra work. If, when I arrive at the site, I see that the foundation does not meet the FHA requirements, I will tell them and hope that they will pay me the minimum rate I quoted. Or, if you want, I can make the same measurements and collect the data needed to design or develop a construction repair plan to transform the existing base into a permanent foundation that meets FHA guidelines.
And this is likely to be even more expensive (in terms of my fees) and, sadly, probably prohibitively expensive in terms of construction. One such innovation occurred in September 1996, when Congress approved the Permanent Foundations Guide for Prefabricated Housing (4930.3 G). The Department of Housing and Urban Development requires that all prefabricated home foundations be certified to receive building permit approval. Modular homes rest around the perimeter of the house rather than on I-beams; prefabricated houses are not normally placed on this type of foundation.
All wiring and plumbing in houses on a slab base must be inside the walls and floor of the real house, which is common in both modular and prefabricated homes. There are three main ways in which the code allows you to build a permanent prescriptive foundation for prefabricated homes. Like the others before it, this base is available for single and double width prefabricated houses. Surprisingly, the code allows for innovation and, since 1996, many manufacturers have been manufacturing more efficient foundation systems for prefabricated houses and mobile homes.
Beyond prescriptive methods for establishing a foundation for a prefabricated house, there are now a lot of innovations. It's important to understand that permanent foundations will qualify you for loans and real estate financing, but they will often be more expensive and take longer to set up. Like pier foundations, single- and double-width prefabricated houses can be placed on top of these types of foundations. As the name suggests, the foundations of small spaces create a 48-inch deep space within the foundation of the house.