Underbelly DIY Cleanup

Repair help for the do-it-yourselfer.
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Thu Aug 02, 2012 11:45 pm

As I continue to DIY and R/R our manufactured home my next project is the underbelly. My one challenge is the space underneath the house. I'm concerned about the space since it is so tight under there it could become claustraphobic (sp) and hard to manuver. What exactly is in this space and why is it so attractive to all the occurrences of dampness, rips of undertermined origen, various little rodents. Is this space the whole length of the home? Why is it necessary to have a special type of covering underneath and is it required that I tape it to enclose the area or can I frame it in without using special cloth material. What makes that area underneath so attractive that it needs to be 'policed' so frequently. Does the area underneath really need all the protection that I read about or can I just seal the homes' exterior around the foundation so as to secure it from all these aformentioned issues. I'm looking for a 'productive' result to the underbelly that I hear so many folks talk about and that once I remedy my situation I am able to assist other homeowners. I'm really interested in hearing of your experiences and what I can accomplish to enjoy my home. Appreciate your thoughts and comments.


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Location: Indiana

Fri Aug 03, 2012 2:09 am

Dealing with the tight space, just take your time, and give yourself a minute or so to get used to the surroundings. I know I need a minute to adjust to the darkness. Im 6'3" 290lbs, so its tough for me but I manage. I also take frequent breaks.

The underbelly is also a good place for animals because its a good way for them to get out of the weather. Many animals tear into the belly to look for a water source, too. As for dampness, allow for some airflow underneath there, and install some kind of membrane on the ground.

As for the underbelly material, it can be patched/taped up/replaced as necessary. The main thing is to seal up any gaps or holes, and not to allow the underbelly to sag down towards the ground. Ive seen people use Tyvec on an underbelly as well. In an extreme case, you could staple chicken wire down there to keep out animals. Might be a little tough to do work down there afterwards, though....
Tip your bartender.....

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Joined: Sun Feb 13, 2011 11:33 am

Fri Aug 03, 2012 3:17 pm

By "underbelly", are you referring to the plastic covering, or the whole crawl space under the mobile?

Either way, that plastic isn't going to stop rodents. The best way to stop rodents is making sure your skirting is sealed tight. With of course, metal screening for the vents in the summer.

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Greg S
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Location: Kingston Ontario Canada

Fri Aug 03, 2012 4:29 pm

Your skirting is the first line of defence against rodents however it will never be 100% successful.
Your underbelly material is important as it holds up the insulation. It,like house wrap, breathes allowing condensation to escape. It also helps to keep out rodents somewhat.

If you do not want rodents under your home the best line of defense after proper skirting is poison.
An individual must enforce his own meaning in life and rise above the perceived conformity of the masses. (Anton LaVey)

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Joined: Sat May 19, 2007 7:57 am
Location: Murrells Inlet,SC

Fri Aug 03, 2012 5:01 pm

#1-Get some lose fitting coveralls. No bare skin and bare feet.
#2- good lighting like a big flood flashlight. Better is a big trouble light and extension cord.
#3- If you meet an animal as big as you are, please crawl fast.
#4- Underbelly covering is insulation since it not warm like a regular basement.
The insulation covering also covers your piping and wiring to keep it warm in winter.
If it is indeed low under there expect to spend time on your belly or back.
Like those great escape movies tunneling they're way out.

There are companies who will do the crawling, inspecting and repair if needed. They may employee "Short People". Good luck.
1987 Craftsman Double Wide 42x28,w/attached 28x12 foot enclosed porch/ re-shingled 2 yrs ago. Original exterior vinyl w/no sheathing.

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Joined: Mon Oct 25, 2010 9:53 pm
Location: Steuben County, NY

Fri Aug 03, 2012 5:04 pm

The belly material is necessary to hold the insulation under the floor. Without it, the floors will be cold(er), and the water lines will be more likely to freeze. The water lines are usually run near the heat ducts to keep them warm enough in winter.
You cannot just seal the skirting, because you then trap moisture underneath, leading to rot and mold growth.
In the site's store you can find tape and adhesives designed for patching. Most regular tapes will not hold.
You should not have any openings in the belly unless someone has cut it for repairs, or larger animals have had access to the area.
Rodents, cats, raccoons, etc. like to get in there because it makes a warm cozy home.
Does your home sit on dirt or a concrete slab?
If on dirt, it is a good thing to have a vapor barrier on the ground, usually 6 mil plastic, to help control moisture.
Also, it makes it easier to slide around underneath.
You can enclose the crawlspace and insulate the skirting if you want, just be sure to leave adequate ventilation, particularly in the warm months, and adequate access points.

There are vents available that operate automatically depending on temperature.

I suggest you order Mark's book from the site. It's a great help.

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Fri Aug 03, 2012 8:39 pm

hi, had couple guys tape up and replace some of the insulation underbelly, i haven't checked it yet,hopefully its all nice and in place.. i guess it was hangin down from when the new pex plastic pipes were installed.. i gonna clean-out under there real soon, then i think i'm gonna dig small 6" deep trench inside the lower skirt molding thats on the ground,thats inside the skirting,then insert 6"piece of aluminum trim in the trench,then bend over the top edge aluminum trim and screw it to the skirting molding thats on the ground,hopefully this will stop the rodents.. gonna put down some poison,but don't know where? not inside the skirting,once the aluminum is in the ground..this is my thought to do,my next thought is to insulate the vinyl skirting before winter,,anyone with ideas ?


Sat Aug 04, 2012 10:05 am


Just posted a reply late last night and logged in just now and no post. Did the post go into cyber space or is it hung up somewhere in the mix.

Just talking out loud

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Sat Aug 04, 2012 10:54 am

I don't know. Sometimes strange things do happen, I have had the same thing happen to me, I have also hit the "full editor" box by mistake rather than the "Submit" box.

"If I can't fix it, I can screw it up so bad no one else can either."


Sun Aug 05, 2012 6:19 pm

Appreciate the heads up Greg.

About this whole 'underbelly' thing. Does the underbelly go the distance of the home? If this space contains the insulation, plumbing, wiring et al why is it not contained within an inclosed space such as thin-coated plywood attached to the foundation? It doesn't seem practical to me to have a space such as this covered only in plastic that allows for varments, rodents, moisture and a whole slew of other problems. If the space was enclosed it would seem to me to lessen the problems already mentioned and not have to repair and replace everytime you heard a weird noise. I could see where one would create an access space for the plumbing in order to get to it conveniently enough but as far as insulation is concerned it would appear to me that enclosing it as mentioned above would work very well. If this resolution doesn't seem or appear practical then what is the real use of the plastic? I like the 6 mil on the ground. Just because we live in a manufactured home doesn't mean we have to treat it like a mobile home. Thease really are well-built homes no matter their age. All that needs to be done is to keep them in livable condition as we would if they were stick-built houses. As soon as I get these problems addressed I'm looking forward to sitting back and enjoying the yard and the house.

BTW Anybody have any good remedies for getting rid of gophers? We saw a segment of gardening by the yard and the host recommended garlic. What say you?

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Location: Weedsport, NY

Sun Aug 05, 2012 7:13 pm

When the home is built at the factory, the insulation is put in place and then the belly material is rolled out and put in place. This is done as one large section before the frame rails are installed. Some homes do have cutouts for plumbing access I have some under the bath tubs to get to the traps.

"If I can't fix it, I can screw it up so bad no one else can either."


Wed Aug 08, 2012 11:53 pm

I've read where folks use 3M adhesive spray to attach belly fabric. I also read some use a special kind of tape. I have something called monster tape. It's similar to duck tape only stronger. I've used this tape in some hard to get spaces and on some plumbing as well as duck work and it holds up to its name. If this tape can hold up under some tough weather and can weather any type of climate -- what say ye about using it to hold up the underbelly. I'm not looking to cut corners. Nor am I looking to do a shoddy job. I'm looking to do a good job without spending a whole lot of money.


PS. Found an excellent resource for getting rid of gophers, rodents. The product is a granulated caster oil granules. A little on the spendy side but extremely effective. Don't buy this stuff from the box stores because it uses a lot of filler material. You need to buy this product online.

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Thu Aug 09, 2012 8:59 pm

I have a couple of small tears, and a couple of places on mine where plumbing and wiring were added and the material not patched up. I asked the MH movers what was best and they said Tuck Tape (the red stuff) was the best thing to use. Mine has a sort of canvas like material, black in colour.

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Location: Western Washington, Puget Sound

Fri Aug 17, 2012 10:50 am

*I* use the spray glue and woven belly repair fabric under my rentals. Works great. I have NEVER seen a tape product - monster tape, gorilla tape, not even military-grade Shurtape - worth a sh*t. It ALWAYS comes away. Lowes has like 3 levels of spray adhesive - I use the high end, like $11 a can, but worth the money to me.

D-U-C-T, btw

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Fri Aug 17, 2012 6:44 pm

Mark has the belly repair tape in the store, it DOES work. You need to apply it, then warm it up to really make it stick.

"If I can't fix it, I can screw it up so bad no one else can either."