What is considered a permanent foundation for a manufactured home?
Constructing manufactured homes on permanent foundations differ from stick-framed homes. Although they use similar building methods, these homes also incorporate techniques gleaned from commercially built structures. So, “what is a permanent foundation for a manufactured home?
Since 1976 with the National Mobile Home Construction and Safety Act (42 U.S.C.), manufactured home innovations keep expanding. One such innovation came in September 1996 when the Permanent Foundations Guide for Manufactured Housing (4930.3G) passed congress. Additionally, this law requiring foundation certification set precedence for manufactured homes to be considered real property. So, what does that mean for you?
What Are Permanent Foundations for Manufactured Homes?
Understandably, with the passing of the Permanent Foundations Guide for Manufactured Housing (4930.3G) these homes became a popular alternative to site building. Moreover, their foundations began transforming. You see, the Guide made provisions for innovators and engineers to establish better methods of making manufactured homes look like a home.
So, What Types of Advances Are We Talking About?
Beyond the prescriptive methods for establishing a foundation for a manufactured home there are now many innovations. But before we discuss them let us review the prescriptive methods established by federal and state guidelines.
Prescriptive Permanent Foundations for Manufactured Homes
There are three main ways code allows you to build a prescriptive permanent foundation for manufactured homes. Here they are:
- Concrete slabs of either 4” or 6” thickness. Additionally, securing the home using metal tie-down straps to the steel beams and slab at intervals established by the manufacturer’s manual. Block skirting must be mortared, reinforced and cavities filled.
- Concrete runners. These are footing strips poured longitudinally the entire length of the home. In particular, these footing strips are made to fit the homes’ beams, marriage line and perimeter. Again, block skirting must be mortared, reinforced and cavities filled.
- Perimeter wall foundation with ribbons. This method replaces the block skirting with a poured wall. Moreover, positioning horizontal footings for all blocking supports and anchoring tie-down strapping for securing the steel girders.
Alternative Permanent Foundations for Manufactured Homes
Excitingly the code allows for innovation and since 1996 many manufactures are making more efficient foundation systems for manufactured and mobile homes. Since this is ever expanding, I will only make mention of a few manufactured home foundation systems.
Before I begin let me say the reason behind many of these methods is:
- A) cost savings
- B) site-work construction speed
- C) better quality and reliability
- D) re-usability
Note) Let me emphasize that the code specifically says that all engineered systems must use concrete in contact with ground. (Not all systems meet this code although they may currently get approvals.)
We recommend choosing a system that meets code now, particularly the requirement for concrete to be in contact with soils. Our reasoning is because nobody knows what the future holds for systems not meeting these requirements.
Methods Using Gravel Pads Meeting All Code Requirements
- Concrete in Contact with Ground.
Methods Using Gravel Pads Meeting Some Code Requirements
- May Not Meet Concrete in Contact with Ground.
Note: Our DURASKIRT™ brand mobile home skirting fits well with all systems we have discussed.
In conclusion, we recommend choosing a permanent foundation system meeting all intents and purposes of the code. This way you will be on a firm foundation for years to come and not just figuratively.