A good marriage is critical to your emotional and financial security. The same can be said about the marriage of two or three sections of a manufactured home. For all of the good work and craftsmanship that goes into the construction and installation of a manufactured home, I can’t help but think that the marriage line joint is the weakest link in the process. If the marriage line is not secure, level, and reasonably tight, problems are sure to creep in! Heat loss, wall and ceiling cracks, carpets and floors shadowing the seams, and doors binding can all be symptoms of a good marriage gone bad.
So, let’s talk a little about the marriage line to make sure we are doing all we can to strengthen this weak link.
Everybody knows to remove all shipping plastic from the home. But it is especially important along the roof line as venting of the roof cavity depends on air flow from one home section to the other. Any plastic left around the roof line can restrict the air flow to properly vent the roof.
Inspect the marriage wall for leftover staples or nails once the shipping plastic is removed. I know they are a pain in the neck, but one staple left in the marriage line can cause big problems.
Inspect the heat duct gasket. If it is damaged, you need to replace it. Was it the shipping plastic or straps that caused the damage? If so, snap a picture and let the manufacturer know! Consider a shield made from coil stock that can be removed once the home is in place.
Look for any electric cables that might get pinched or otherwise damaged when the sections are pulled together. Re-secure them to prevent damage.
Is the marriage line gasket intact? Damaged? Properly placed? If you read my previous posts, you should know I think this is a big problem area. Read my post from April 17, 2017 “Would You Like That Supersized?” for some other thoughts on this gasket.
Gaps between the A and B sections of a home can lead to structural problems over time. While professional installers generally don’t pay much attention to shear walls (the walls that transfer wind loads through the structure of the home to the anchoring system), it is very important to understand that in many two-section manufactured homes, all of the shear walls are found in only one of the sections. The manufacturer is depending on you to make a structurally sound joint to transfer these wind loads across the marriage line to the section of the home with the shear walls.
Wind loads are safely transferred only when you properly fasten the sections together. Basically, a structural, tight fitted joint is required in order for the home to withstand wind storm. No gaps in marriage line!
The manufacturer’s installation instructions states, “Shim any gaps up to one inch between structural elements with dimensional lumber. If any gaps exceed one inch, re-position the home to eliminate such gaps”. Read that carefully. It means gaps are not permitted! You must either use shims up to 1″ or get the home sections closer.
This is very important not just at the floor, but the walls and roof as well! Gaps between sections can cause the screws, nails, or lags to shear off, pull out, or fail at the exact time they are needed the most!
Make sure to stagger your fasteners (A half/B half), and be sure they don’t split out the lumber. The lags or screws you use must properly penetrate into the receiving members by 1 ½”. You might need to use longer fasteners than the ones provided by the manufacturer.
If you are using straps at the roof, it is critical to remember that this joint also needs to be solid and tight. If the staple crowns or nail heads cut through the strap material, the strap won’t be able do the job that the manufacturer intended. Make sure your fasteners go through the blocking, beams, or rails provided, and not into the truss!
Take a few minutes before your next set and double check the manufacturer’s instructions for fastening the marriage line. Take a lot of pictures, and give some feedback to the manufacturer (the Quality Assurance Manager in this case). They might be able to tweak things at the factory to make your job easier. In fact, if you aren’t on a first name basis with the QA Manager at the factories you deal with, you need to change that. These guys are a wealth of knowledge! Every QA Manager I have ever met wants to produce the best homes possible. What they are lacking is feedback from you!
A good, strong, tight marriage line is not always easy and at times very difficult. But, with a little tender loving care, you will get that good marriage line, and we all know, a good marriage is well worth any price!