Leaks galore

[jstar]

I bought a new to me TT that is in really great shape and had very few areas of de-lamination. I noticed that the dealer the folks I bought it from who they got the unit from a year ago, went over it and did a bunch of great looking caulking and sealing of the roof, joints etc. However we have had a lot of rain since I bought it and today I noticed some swelling at the rear corner where there was some already but it looks much worse. I have a moisture meter (i'm a home inspector) that is non intrusive you just run it along what ever and it tells you the percentage of moisture in the product. I wasn't sure if it would even work that great but guess what? It does and it showed my a ton of leaks I have. all around the slide, the rear where I saw the swelling including the very back wall and under several other openings. Most everything looks sealed up great which is very disturbing also. What is one to do?

[Golden_HVAC]

I like the pictures in this post.

Fred.

[stufarmer]

Band-Aid repairs are what you do on the side of the road. This is a Major Roof to Floor repair. The strength of the entire area has been affected.
I apologize if this offends anyone, But you can not fix rotten and possibly molded wood under (any) circumstance.

[westend]

myredracer wrote:
Do holes in the floor need to be sealed up? There is a hole next to our furnace for the ducts into the underbelly space and it's big enough to throw a cat through it. Plus there are various holes for plumbing into the underbelly.

Is there a suggested CFM? We have two Fantastic fans and it would be nice if that does the job.

I want to start doing this annually. I like the idea of using a pass-through door opening.

I guess I would seal any big holes up permanently just for rodent control if nothing else. For performing the test, jam a rag in there. The places where the pressurised air can go is through ceiling vents, heater intake and exhaust, air conditioner plenum, vent fan duct, and through plumbing into vents or tanks.

I'd suggest to cover up the easy ones and don't sweat the small stuff. We're not trying to make the RV launch into the vacuum of the high atmosphere. I cover the vents with cardboard and install the sink stoppers. The truth is, with a blower that can deliver enough volume to raise the pressure 1" WC, even the escaping air out of windows and doors won't be a significant factor.

I've shown my method before, the furnace blower in a window. I think, for the RV'er that wants to DIY, introducing air from the outside through a storage hatch where there is am access to the inside or through a window is the easiest. You can get crazy and make adaptors to fit a ceiling vent or get all scientific and pull the air in through a vent like sealtech does but the bottom line is moving enough volume in to achieve .5"->1.5" WC. A simple DIY manometer can be made and attached to the board or plate used to mount the blower output. I used 1/2" vinyl tubing, made a loop and attached it to a piece of plywood. I filled it to equilibrium with blue food coloring and water.

Harbor Freight sells this ventilator for $80 and I'm preety sure it will move enough for most RV's

[qtla9111]

When using the Fantastic Fan method with the fan in reverse, do you leave the vent cover closed to create a vacuum? If I'm understanding it correctly.

[jstar]

myredracer wrote:
Do holes in the floor need to be sealed up? There is a hole next to our furnace for the ducts into the underbelly space and it's big enough to throw a cat through it. Plus there are various holes for plumbing into the underbelly.

Is there a suggested CFM? We have two Fantastic fans and it would be nice if that does the job.

I want to start doing this annually. I like the idea of using a pass-through door opening.

I certainly would fill the voids as its an entry point for rodents etc if nothing else. Seal, Seal, Seal, baby!

[myredracer]

Do holes in the floor need to be sealed up? There is a hole next to our furnace for the ducts into the underbelly space and it's big enough to throw a cat through it. Plus there are various holes for plumbing into the underbelly.

Is there a suggested CFM? We have two Fantastic fans and it would be nice if that does the job.

I want to start doing this annually. I like the idea of using a pass-through door opening.

[westend]

delad1954 wrote:
DANG.....How do you know so much about leak testing and Sealtech ?

Just lucky, I guess-- lol.:B
I test mine about every year using a blower. Part of that is influenced by the type of roof I have, a roll-seamed aluminum roof. The previous owners slathered all types of sealants to stop leaks--caulk, RTV silicone, asphaltic roof patch, etc. I removed all of that and replaced it with Eternabond tapes. My annual leak testing has turned up no leakages where the Eternabond has been applied. I sometimes find a leak through the siding but Geocel tripolymer sealant has eliminated all of those.

Believe me, when I restored the Starcraft I did extensive sealing in those areas where I thought water intrusion might be a problem, I probably used 10 tubes of elastomeric sealant between siding and frame, frame to roof, and any other joint accessible. I still had two dozen small leaks. Those leaks were uncovered by the pressure test.

[delad1954]

The Sealtech Leak Test can be done on pretty much any RV... Regardless of what kind of siding it my have. They all tend to leak after time ! I would recommend getting your RV tested once a year if you are driving it around... Just as a preventive measure...New leaks can open up at any time.

[jstar]

I've noticed all the photos and videos I have seen of this seal test method have been on aluminum sided trailers but I have not seen one with Fiberglas smooth sided ones like I have, has anyone got experience with those type of TTs?

[delad1954]

DANG.....How do you know so much about leak testing and Sealtech ?

[westend]

delad1954 wrote:
Yes you can probable DIY but the tricky part is as you stated 1.5 of water column..... to much pressure and you open up leaks that would not normally be an issue....If you can find a service center that does the Sealtech Leak Test that would be the next best thing !

It's doubtful that using an additional 1" WC of pressures is opening up or causing additional leaks to be found. One has to think in the overall structural aspect of the situation, not in a limited air pressure value way. The Sealtech operators have a range of values used in air pressure when testing. Most are centering on a differential of 1/2" WC. That is enough to turn up any leaks.

As stated in my other posts, I have a trailer that has been sealed in it's wall structure more than a typical RV. Beyond form fitting foam board and a taped plastic film vapor barrier, is also a 1/4" foam insulation board and then, paneling. I observed a dozen leaks through siding and around windows in my first test. I would assume the air is leaving the interior around electrical box openings and through staple holes in the plastic film. Increasing the pressure differential beyond the 1'WC I used would only make bubbles at leak points form faster and bigger. It would not create additional leak points.

FWIW, IMO RV owners don't have access to equipment that would cause a harmful pressure differential. There would have to be a trailer that has large structural issues and the pressure would have to be raised beyond what can be achieved with available air handling equipment. I've used blowers with basically a 4' airplane propeller mounted in a cage to move air when remodeling. These are used to move any dust and evacuate it from the house when working. If it was reversed and the house was sealed, it may compromise certain structural elements but that is still doubtful, IMO. There are just too many small air egress points.

[delad1954]

Yes you can probable DIY but the tricky part is as you stated 1.5 of water column..... to much pressure and you open up leaks that would not normally be an issue....If you can find a service center that does the Sealtech Leak Test that would be the next best thing !

[fallsrider]

westend wrote:

fallsrider wrote:
I can see where the worksheets, or trailer diagrams, would work. My only concern would be finding a pinhole leak again just by going off a diagram.

I guess a grease pencil would work as mentioned, since I always clean an area with denatured alcohol before applying caulk.

Just thinking it through...

It's not that hard. If you have a pinhole in a siding joint, you're probably going to be sealing more than just the exact location when you apply caulk.

Makes sense. I actually fear doing this test a little bit. I'm afraid the diagram of my trailer might look like I shot it with bird shot from my 20 gauge from about 20' away! 😄

No leaks yet, but I need to keep it that way.

[Huntindog]

jstar wrote:

westend wrote:

fallsrider wrote:
I can see where the worksheets, or trailer diagrams, would work. My only concern would be finding a pinhole leak again just by going off a diagram.

I guess a grease pencil would work as mentioned, since I always clean an area with denatured alcohol before applying caulk.

Just thinking it through...

It's not that hard. If you have a pinhole in a siding joint, you're probably going to be sealing more than just the exact location when you apply caulk.

Weep holes do not let air or water out of the inside of the unit they are for any moisture that gets between the frame and the glass to come back out. No you should not be getting bubbles at the weep holes. Did you get bubbles anywhere? If so then it worked.

No bubbles so far. But it is still dark and I won't deal with the roof till dawn.
I can insert a small paperclip into the weep holes and it will appear inside... I would think that I should be getting bubbles there?