Mobile home is sweating

Not my job, but a roofer buddy’s project.

Mobile home was re-roofed in first 1/4 of 2009; single story mobile home with 3T & 15# @ a 1/2 lap. None of the old felt was removed with 2 or 3 sheets of OSB (non foil face) replaced.

Mold growing in the bathroom, excessive moisture & condensation showing on the exterior of the shingles for around 9 of the 12 turtles exhaust vents - they are a combination of round & square vents.

Affected areas are ONE of the bathroom exhaust pipes & the two bathrooms are around 45 ft. apart (the other bathroom exhaust pipe doesn’t show any mold… black spotting… where one bathroom exhaust vent does).

Interior sheetrock seems to be sold & firm for the affected bathroom.

The vent setup was double checked after the reported moisture issues & it’s fully intact with no issues.

This mobile home is about 9 years old, it has about a 6" soffit with a continuous venting design (can’t guarantee it’s not blocked with some kind of insulation as no visual inspection has been performed). Insulation is a blown in variety (not rolls or batts) & when the roof was partially opened up to check the bathroom vents for intact, the insulation appeared dry.

The air conditioning DOES duct through the floor & NOT the attic; he said it was pretty humid in the house when he inspected it & the air here in Central Texas was listed @ around 80% relative humidity according to my web search.

I’ve already given him the business for not taking any photos…

I’ll hang up & listen.

Where are you heading with this Ranch?

Where’s the sweat & condensation coming from?

It appears to me that he’s checked for possible issues coming from bathroom steam & A / C ducting…

I didn’t ask if they added more vents than were on the roof before they undertook repairs.

Any vapor barrier on interior? Was there a problem before the new roof?

since it’s showing up around so many of the vents I would guess thar when they blew the insulation they blocked most the soffit vents, are the 3 unaffected vents in the same area as the bathroom with no problem? Could be that area is getting enough air flow to stay dry while the rest isn’t, somthing like that with the venting is the only thing I can think of without actually seeing it

lety me add to that, most mobile style homes have the insulation so you can not properly ventilate the roof. In other words he is well screwed, have to pull all the decking off, put baffles in and the put the deck back on and shingles. then you can ridge vent the thing and the problem is solved. As far as bathroom vernt they all must be ventilated it could be traveling if exhusted in attic, also check if they have a fan in kitchen that will also go to the attic. We all know hot showers build steam and will condinsate. Hence mold. Thats how i bid and do the. Hope this helps. God bless.

That is pretty much what I have been finding also.

This is what the insulation looked like in one we fixed.

http://www.roofing.com/images/topics/8730/img_1258765738.jpg

There was a decent amount of insulation there but there were large gaps in coverage allowing a lot of heat loss.

On this one there was a visqueen vapor barrier in the ceiling but there still was a little mold.

We fixed it by adding r-19 insulation over the entire ceiling, added rafter vents, installed smartvent, extended 4 pipes, replaced water heater pipe with new, and installed ridgevent.

The problem here was ice damming and leaking though.
It could be the same things causing your condensation problems.

It’s a doublewide mobile home, so ridge venting won’t work.

The way these are designed is shown with the last photo; they have divided sections with plywood making a “Side A” & “Side B”… then are bolted together right down the center @ the ridge joint.

There’s no ability to put a ridge vent in place on 99% of all mobile homes due to this blockage.

I’ll fwd this thread to him & he may reply with other commentary or come back to me for further discussions.

[quote=“RanchHandRoofing”]It’s a doublewide mobile home, so ridge venting won’t work.

The way these are designed is shown with the last photo; they have divided sections with plywood making a “Side A” & “Side B”… then are bolted together right down the center @ the ridge joint.

There’s no ability to put a ridge vent in place on 99% of all mobile homes due to this blockage.

I’ll fwd this thread to him & he may reply with other commentary or come back to me for further discussions.[/quote]

You mean like the one pictured?

You can use smartvent as a ridgevent also.

Some insulation installers don’t take their job seriously enough. Thats a lesson I’ve learned this year.

I agree, a good insulator needs to be detail oriented.

[quote=“-Axiom-”]
You can use smartvent as a ridgevent also.[/quote]

Damn good idea

If I were specifying the ventilation, I would use a drip edge eave vent on the gutter edge. Cut ventilation holes through the doubled center wall and install as many power vents as required for the attic area.

Depending on the homes consruction you can infact use ridge vent seen single beems that allow it. Aside from that the insulation and venting into the attic are the problem in my eyes.

I have yet to see a mobile home (double wide) that would be able to use ridge vent. none of them were even close.