Basement air duct

INSPECTORBOB · 02-06-2017, 10:24 AM

We have a 2000 Itasca Suncruiser 35U, which was recently attacked by mice. In searching for the sources of entry, I found some hidden MAJOR openings. The bathroom sink cabinet has two..one where the drain and water pipes enter from the floor (pretty obvious), and also, the biggest one, is under the drawers (behind the magazine rack). This is about a foot square, and has a very large numbers of plumbing and electrical wires entering the coach. You can actually see the ground from this opening!

Adjacent to this cabinet is the bedroom wardrobe with drawers, and adjacent to this is the laundry cabinet. Finally, adjacent to the laundry cabinet is what Ia believe is the return air duct and grill for the basement air. (Drawing is attached).

The disturbing thing is that these are all connected, and open to one another, which means that rodents have full access to any of these areas by simply entering the large opening under the bathroom cabinet. Furthermore, there is a sliding door which pockets in between the bath and bedroom, and a large opening under this door that gives rodents full access to the interior of the rig. I have partitioned off each of these areas with plywood, to eliminate this from happening. Sorry for the long background, but here is my question:

Did I make a mistake by closing off each of these areas? I am particularly interested in if it was ok to wall off the interior of the return air duct. Why would this have been open to the outside, and is it necessary to leave it open? It seems to me that if it is the return air duct, this should be completely isolated from outside the rig. Note that I did not close of the grate of the duct, which is in the bedroom. Any thoughts??
Thanks
Bob

Jim_HiTek · 02-06-2017, 10:51 AM

Sounds like they did both a poor job of engineering, and a lame attempt at building it following those engineers drawings.

The air intake should be blocked off from any outside air. Any openings you suspect might be a mouse entry, but aren't sure they should be blocked off, cover with metal screen. Tight weave.

BTW, there is normally some way for warm air from inside the rig to drop down into the basement compartments to prevent freezing. The freshwater compartment and the black and grey compartment. But that is passive, not forced air, and openings can be covered with steel fabric.

Marguerite66 · 02-06-2017, 11:04 AM

We had the same problem in our RV. We put small squared wire where the air duct was, ( cat found that opening for us ) kept and air flow in and the cat out, and cut very thin pieces of plywood cut to fit around the pipe under the bathroom sink and glued in place. So far no more mice.

Ret Smokey · 02-06-2017, 02:50 PM

I have the same year and model with EXACT same hole. I keep a loaded 410 with bird shot for the rodents. Have had mice, and red squirrels in ours. I see absolutely no way of blocking that enormous hole with all the wires running every direction possible. It is definitely one big f/u by Winnebago.

KSagal · 02-06-2017, 03:51 PM

I do not have this kind of a camper, but in the past, when the hole was large or odd shaped with lots of stuff going thru, I have used an insulating product called 'great stuff'.

It is a can with aerosol foam sealant. I get mine at Home Depot. There are several types, including one that is supposed to be rodent proof.

All you need do is use tape or cardboard to make a very temporary trap, and spray it in. It expands around all the bits and it will seal things well.

Of course, if you want to pull one of those wires afterwards, it may be more of a challenge, so be aware...

tderonne · 02-06-2017, 03:58 PM

Those openings are designed in and OK.

The seal that any rodents should not be able to penetrate isn't at the floor surface, it's below that. You shouldn't be able to see outside when looking down the holes though, only into the basement compartments. were you by chance seeing out an open compartment door? Sealing at the floor level will only ensure that the mice stay in your basement, hardly a solution.

INSPECTORBOB · 02-06-2017, 04:51 PM

Quote:

Originally Posted by Ret Smokey

I have the same year and model with EXACT same hole. I keep a loaded 410 with bird shot for the rodents. Have had mice, and red squirrels in ours. I see absolutely no way of blocking that enormous hole with all the wires running every direction possible. It is definitely one big f/u by Winnebago.

Bob, thanks for your response.

You're right. No way to seal off at the floor level, but if you want to seal it off, I just cut a piece of plywood that fit between the framing of the cabinet, then cut a slot in it to accommodate the couple of vertical plumbing runs. Then, I just slipped it in the cabinet OVER all the wires and horizontal plumbing, but had to slope it slightly downward toward the front, to allow the mag rack to slide back in. I fit a small piece of plywood over the opening I created to accommodate the plumbing, and closed of most of the small opening around the plumbing. For the rest of the remaining opening, I filled it with brass wool and silicone sealer.

Note that before doing this, I also sealed off the area that was open to this which went under the sink cabinet. Just used small pieces of wood between the many bunches of wires and plumbing, then sealed them in with silicone.

Bob

INSPECTORBOB · 02-06-2017, 05:00 PM

Quote:

Originally Posted by tderonne

Those openings are designed in and OK.

The seal that any rodents should not be able to penetrate isn't at the floor surface, it's below that. You shouldn't be able to see outside when looking down the holes though, only into the basement compartments. were you by chance seeing out an open compartment door? Sealing at the floor level will only ensure that the mice stay in your basement, hardly a solution.

Tim, thanks for your reply.

Unfortunately, yes, it is open to the outside. It also partially opens to the wet compartment, and that is definitely open to the outside. What led me to find this is mice had built nests in the wardrobe drawer and bathroom drawer. Following the trail exposed the hole in the floor behind the mag rack. The plumbing and electrical coming thru the floor was full of mouse poop. Maybe they came in another way, and just settled there, who knows? I did seal it off, so we'll see what happens.

Bob

AFChap · 02-07-2017, 09:01 AM

Quote:

Originally Posted by INSPECTORBOB

Unfortunately, yes, it is open to the outside. It also partially opens to the wet compartment, and that is definitely open to the outside.

Open to the basement area, yes. Open to the wet bay, yes. I have those areas in my coach too. But where is it open "to the outside"?

As indicated, these wire-ways/air-ways are designed in to provide air flow from the passenger area to the basement to provide a bit of passive heating and cooling to those areas. But the basement (as designed) is sealed off from outside, unless you are talking about the hose port & the electric cord port. As Tim indicated, sealing the airways between the passenger compartment and the basement is not a solution ...that is like trying to keep stray cats out of your stick house by closing interior doors and ignoring the open front & back doors. The place to spend your time is underneath the coach, finding and closing any possible access holes, crevices, etc.

INSPECTORBOB · 06-16-2017, 08:11 AM

What I thought was an opening to the outside was actually light coming in from the opening for the hose in the wet box. However, I did find that this seemed to be the entry point. My wet box door was closed and locked previously, so I never thought to check there. But the mice appear to have managed to squeeze in between the circular door and the bottom of the wet box, even with the door closed. They did chew around the edge of the opening somewhat. There is some foam in between the door, and the bottom of the box that they also chewed to gain entrance.

From there, it was an easy shot to the area under the shower and bathroom sink, and then off to wardrobe and return air duct. The area behind the wardrobe drawers is open to the underside of the sliding bedroom door, which is open to the living area, which allowed them to roam the rig. Then, over the kick plate in the kitchen, which put them under the drawers.

From there, it was open to the sliding pantry, and to the entire row of compartments on the right side of the rig via the opening for the wiring under the kitchen drawers. I also removed a sheet metal cover which is behind one of the outside compartment doors below the refrigerator (I can't recall if it was the 2nd or 3rd compartment behind the entry door) to follow some of the wiring and found a a nest in there as well.

Thanks again to everyone for their replies and suggestions.

jabass · 10-24-2017, 09:02 AM

If you park your RV at home you may want to try rope lighting around the tires and pads where mice could crawl up ....I have used this for about six months and no mice have gotten into the RV. costco now has rope lighting that allows multiple modes.....

staggerlee · 10-25-2017, 06:53 PM

Go to the feed store and get some "One Bite".
Break off a bar and put behind each wheel..

They will run, looking for water, not in your coach.
Our stick house suddenly got over run with mice last year. I used sticky traps and had 5 on one paper over night.
Called exterminators, and they put down poison, I thought NO, they will die inside and the smell.
They were right, none of them smelled, and they went back outside looking for water.