Extensive rotted rim joists

[romdos11]

Hi all. This is my first post, and I have learned a lot by reading on the forum. Sorry this is rather lengthy.
I have a 1996 Skyline 16 x 80 that I got from a friend of mine after he bought a house. He bought the trailer new. Around the same time we bought an old farmhouse that needs totally renovated and were looking for a mobile home to put on the property to live in until we can fix up the farmhouse.
Since moving it to my property, and getting a much closer look at it, there are several feet on both sides of the trailer where the rim joist is rotten, and the underbelly material isn't even connected because the staples have just fallen out. The siding is some kind of woodboard and it is also rotten in several places, especially where the rim joists are rotten.
All the utilities are connected and I need to get the skirting on. I am using some steel roofing sheets that I found on the property which just happen to be the perfect size for skirting. Unfortunately, I don't know what to do about the rim joists. I need to fasten the underbelly material to SOMETHING and I am using a J channel to hold the steel pieces onto the trailer, which also need to be fastened to SOMETHING.
I am considering cutting the siding at the level of the top of the rim joists, then just cut them out and attach new wood to the floor joists which all seem to be ok so far. Very little rot has permeated all the way through to the floor joist side, so there's good wood to attach the new rim joists to. The thing that worries me is there's always surprises when you start ripping things apart.
I guess my question is, is there some quick and dirty way to get this trailer ready for winter without redoing the whole outer shell? In particular, how can I reattach the sagging underbelly fabric without replacing the rim joist? I can place the J channel a little higher up on the side if necessary to get it attached to some good wood, but I can't for the life of me come up with a fix for the underbelly.
Ideally, I would pull off the old siding, support the walls, and get rid of the old rim joists and put on new ones then add insulation and put smart siding on the outside. I don't have the time or money for that right now, as I am renting a place and making payments on the new place until I can get into the trailer.
It's November, and I'm up against it in terms of getting the skirting on and getting the underbelly closed up against cats, rodents, marsupials, etc, not to mention COLD! Also, I have moderately good woodworking, electrical, plumbing skills, which means I usually have enough sense to avoid jobs that I'll end up goofing up!
All and all help/suggestions will be greatly appreciated! Thanks in advance guys!
P.S. I HAVE downloaded the mobile home guide and have looked at it too!

[Greg]

Since your back is against the wall time wise your quickest option may be a case of spray foam to get you through the winter. That may buy you time to plan better repairs in the spring.

You will find rim replacement to be time consuming but not a terrible job.

Greg

[romdos11]

So do you mean I should just spray some great foam in the openings where the underbelly fabric is hanging loose?
I was wondering if I might be able to seal up the underbelly by gluing a patch of underbelly material on top of the existing material under the trailer, then extend the reach up higher to where the wood has some integrity and staple my patch piece onto good wood. I found this underbelly patch kit here:
http://www.aberdeenhomerepair.com/store ... -p2930.php
I also saw a YouTube video where a guy patches an underbelly and looks like it holds pretty well. Not sure how it would do under tension though.
Here's a photo of the worst area. There are a couple of other spots like this but more of the wood is intact

[Greg]

Belly repair is one of those areas of "what ever works" I don't really think there is any tried & true method, It seems like what works for one doesn't for others.

Greg

[suspiria_2]

caveat--i know nothing about construction.

would it work to get some of that adhesive waterproof roofing membrane, attach that to the side of the house (above the level of damage, to something that looks secure), with the free end extending past the edge of the wall and then securing the edge of the belly plastic to it underneath. you can also use some nails or staples, because those membranes are self-sealing.

it might be hard to imagine what i'm saying. but basically, imagine taping the lower edge of the house, wrapping the 3 foot "tape" (roofing membrane--ice and water shield, i think it's called) around both the joist of the house and underneath to secure the belly wrap. you can then apply some other taping/sealing to the seam, but basically wrap the water seal membrane around both of them as if they were part of the same package.

i think i just made my description worse. but it would waterproof!

[Greg]

I doubt that would work. Belly material is one of those materials that is tough to get things to stay stuck to, It may stick for a while but only a short while. Mark has belly tape in the parts section of the site. It requires a clean dry surface and a heat gun helps make it stick.

You can also do a search of belly repair and look for posts by JD. He uses a spray adhesive method that works well for him.

Greg

[romdos11]

Thanks for all the timely advice. Suspira, I know what you are talking about and the process you described is exactly what I did, except I ended up using tarp from WM and some auto adhesive also from WM.

IMG_0940.JPG

My main concern is keeping varmints out of my floorboards, and, of course, water too. (Although it would seem water has been getting somewhere by the looks of my rim joists)
I just followed the directions on the spray glue and it stuck like a charm. How long it will stay there remains to be seen. Greg's comments worry me a little bit. I was going to get the Sta'Put and some underbelly material, but didn't have the time to get it shipped here, so we will see what happens. In my particular application, it's not really under much tension...I just needed to seal up those exposed edges. Also the glue seems to hold way better under sideways tension than pulling apart forces. I tested a piece of tarp glued to itself and it got harder and harder to pull apart over the course of a few days until it tore holes in both sides when I really tried to rip it.

[Greg]

I found JD's post on what he uses. He's a pro so he knows what he's doing.


Yes, the poly type underbelly sheeting, which is available at this web site, http://www.mobilehomerepair.com/Order2.html#catalog , is the stuff to use. I use a high strength spray adhesive to install it and that works for the old buffalo board, the cardboard type and the poly sheeting. The product "Stay-Put" is excellent, and also available at that same link. At the home stores, I use 3M High Strength 90 spray adhesive. Do not use 3M 77 which is like hobby stuff. When attaching to the cardboard or buffalo board (sound board) material, you will need to spray the adhesive on cardboard material and let it thoroughly dry. Then spray again with he repair material to install. Basically, you are using the adhesive as a primer on those porous and rough surfaces.

Whenever possible, I will also anchor down the belly material on to rim joists and regular joists by nailing on a strip of 1/4" plywood with the edge of the belly material wrapped up around it. When attaching the belly material to just the old belly material, I make sure that everything is real clean and cut the repair material to have a large overlap to bond to.

As far as insulation placement, I would not veer from the manufacturers design, especially if you live in an area that freezes in the winter.
☯JD♫
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All information and advice given is for entertainment and informational purposes only. The person doing the work is solely responsible to insure that their work complies with their local building code and OSHA safety regulations.
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