Often times I am asked “what are the most common problems with manufactured home installation?”. That generally leads to a follow up question, “which problems have the biggest impact on the home?”.
It might be better to deal with these questions separately, starting with the four most common problems with manufactured home installations. Next week, we will tackle the issues with the biggest impact on the home.
#1 Bottom Board Holes
Folks almost always underestimate the job of the bottom board and as a result don’t think holes or tears are important, but they are! Always remember, the bottom board (or belly board as some call it) is the pressure envelope enclosure for the floor cavity of the home. A hole in the bottom board can be worse than leaving a window open all winter. The floor cavity in a manufactured home is a conditioned air space. Unconditioned air from the crawl space will cool off heat ducts in the heating season and in the cooling season, warm humid air can condensate on the cooler duct work leading to condensation. In the winter, water supply piping and drain lines can freeze, not to mention the general heat loss that leads to very high utility costs.
As the installer, make sure to mend any holes in the bottom board. Use products, those designed for bottom board repair (not duct tape). Inform the homeowner to keep an eye on the cable TV man, telephone man or anyone else that might be showing up after you are gone. They are notorious for cutting open the bottom board without a thought about the problems they are causing.
#2 Bonding Wire Attachment
It’s that #8 bare copper wire hanging off one of the chassis of a two-section home, waiting for the installer to connect it to the grounding lug on the other section. This wire is needed to bond the home section without the electrical panel box to the home section with the electrical panel box. I think that this a requirement that is simply overlooked by a lot of installers. You know the old saying, “out of sight, out of mind”. The installation check list (see blog entry from January 9, 2017) is a great tool to help remind installers about this important issue. Start using it!
- Footing Configuration
I have seen a lot of problems with footings over the years, but the number one problem is what I call the “mushroom” shaped footing. This is generally the result of the installer using too small of an auger, and pouring the footing much bigger at the top to create the appearance of a large footing (giving it a mushroom shape).
Not only does the “mushroom cap” generally break off, (as in the picture above) but in short timer the pier block will break due to uneven loading. Not to mention how these types of footings are most likely lifted by frost.
The best footing is “bell” shaped, a little wider at the base. Just the opposite of the mushroom.
- Heat Duct Crossover
With the advent of the through the floor heat duct cross, I thought that problems in this area were a thing of the past. Boy was I wrong!
The fiberglass gaskets at these crossover areas are subject to some significant damage from the application or removal of the protective shipping plastic applied to the marriage wall at the factory, or just from the friction of aligning the home sections.
A few years ago, we came up with what I believe is a simple solution to this problem. An “L” shaped piece of coil stock (sheet aluminum) high enough and wide enough to completely cover and protect the gasket while the home is being set. The bottom leg of the “L” is used to secure this “shield” to the bottom of the floor with a couple of screws. After the home is in place, remove the screws and pull the shield out.
A few friends have tried it with great success!
Let me know it you decide to give it a whirl!
OK, there were my four most common installation problems. Next week, we will talk about installation problems with the greatest impact on the home.