Is underbelly material even necessary?

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brianginaz
Posts: 12
Joined: Wed Feb 10, 2016 2:19 pm

Fri Feb 03, 2017 12:19 am

Prior to moving into our current home (a Palm Harbor Double Wide 1994) we lived in a stick built home on a stemwall which had 2X6 joists, no insulation underneath in the crawl space, and no belly material whatsoever. All the plumbing was installed in the crawlspace much like a manufactured home and the only difference really is that the AC ductwork was in the attic. We never had a problem with this setup which was typical of the whole neighborhood. The Winter lows could dip into the high teens to low 20's and the summer highs reached about 100f. This is in AZ so very little humidity and precipation.

Now fast forward to today. We moved down to the Phoenix area where the temps are in the 40's in the winter and up to 118+ in the summer. And after having crawled in our crawlspace countless times making plumbing repairs, repairing the underbelly etc.. I'm wondering... our previous home was just fine with nothing but exposed joists underneath. Is all this underbelly stuff, and insulation, REALLY necessary in our situation?

Any thoughts?


Craigrrr
Posts: 38
Joined: Wed Aug 03, 2016 10:29 am

Fri Feb 03, 2017 4:13 pm

I too am in Arizona ..Mesa and I dont see a need for the underbelly material here, pipes do not freeze and the critters are scarce besides scorpions and common spiders etc... No coyotes in my crawlspace either :)

yakima4$
Posts: 80
Joined: Tue Oct 20, 2015 11:02 pm

Fri Feb 03, 2017 5:24 pm

The belly skin solves multiple code issues .
MFG homes have only one layer of flooring/decking. It stops moisture,odors and eliminates the higher probability of floor warping.
It also is a pressure envelope that is aimed at restricting air movement into the walls, odors coming up around pipes and holes cut out around tubs/showers and draft stopping for fires.
I wont get into all the details but if you go to sell or REFI not having a belly skin is a big red flag.
Your home is your castle and consumers do what they want.
Take it from someone who gets called by banks and insurance company's to perform inspections on MFG homes for sale or a REFI leave it in place.

brianginaz
Posts: 12
Joined: Wed Feb 10, 2016 2:19 pm

Fri Feb 03, 2017 5:35 pm

Yakima,
I don't intend to rip mine out but I was just noticing that this manu setup is identical to my previous stick built and we've never had any issues with just open joists. The stickbuilt had only one layer of OSB subfloor, vented crawlspace etc... no issues with it being open like that.

If I ever had to redo the ductwork I would think long and hard on whether or not I wanted to repair the belly or just insulate the duct and call it good. :shock:

brianginaz
Posts: 12
Joined: Wed Feb 10, 2016 2:19 pm

Fri Feb 03, 2017 5:39 pm

Craigrrr wrote:I too am in Arizona ..Mesa and I dont see a need for the underbelly material here, pipes do not freeze and the critters are scarce besides scorpions and common spiders etc... No coyotes in my crawlspace either :)

Craig, cheers fellow valley brother! The east valley seems to be a popular place - I'm out west in Surprise far from the city. :D


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Greg
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Joined: Wed Feb 28, 2007 8:01 pm
Location: Weedsport, NY
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Fri Feb 03, 2017 5:46 pm

brianginaz wrote:Yakima,
I don't intend to rip mine out but I was just noticing that this manu setup is identical to my previous stick built and we've never had any issues with just open joists. The stickbuilt had only one layer of OSB subfloor, vented crawlspace etc... no issues with it being open like that.

If I ever had to redo the ductwork I would think long and hard on whether or not I wanted to repair the belly or just insulate the duct and call it good. :shock:
Most stick built homes are built on either a basement or concrete slab. Most mobiles are on piers with dirt. If you are on a concrete pad that would give you a moisture barrier. It's your call and you may never have a problem until it comes time to sell.

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

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