R19 Insulation and Heat Pads for Underbelly

[newbold1]

I have a 2013 Jayco White Hawk 30DSRE which has an enclosed underbelly but was not advertised as all weather or climate shield.

I plan to add R19 vapor barrier insulation to the entire bottom of the trailer (except where the slide bars might catch the insulation) and I am also adding holding tank heat pads to the fresh, grey, and black tanks. I will be encapsulating any water lines I see in R3 pipe insulation.

Has anyone else done this and if so what can I realistically expect?

I have already done a bit of camping in 20 degree weather and haven't had any issues so far. The floor gets cold but the pipes didn't freeze. I am wondering if these modifications might allow me to handle sustained temperatures in the 10-20 degree range.

Also, in the summer, will the added insulation to the floor make any difference in being able to retain more of the cold air from the A/C? I have the 15K unit and it does a pretty good job. It only struggles when the outside temperature is about 95 or above and the trailer is not in any shade. Then, it can barely get to 72 degrees inside the trailer and takes a long time to recover if someone opens the exterior door. Could I expect that this might improve a little with the added floor insulation?

I'm just anxious to get this done and in the meantime am hoping to hear other people's experience with this sort of modification.

[BigJohnD]

I haven't done that, but that's how our Cedar Creek was. Heat pads on all 5 tanks and a frame width blanket of 6" insulation from front to rear. I'm sure it can't hurt to give it a shot. All it can do is help. On the heat pads, location of your dump valves makes a difference too. If you have exterior dump valves, then you're likely going to have freezing waste pipes regardless of the heat pads since water will stay in those lines. They do make products for the pipes as well. On our CC, the tank valves were right at the tank in the belly, so no problem with freezing drain lines. I'm sure you've researched, but the only way heat pads work is by maintaining some water in all of the tanks that have them. Just food for thought.

On the AC, the biggest issue we've ever faced with heat gain is the windows. I don't care if they're dual pane or not, radiant heat makes it in. Insulation in the belly won't help too much with keeping cool, but won't hurt either. In that case, we've always taken the foil backed bubble insulation (about 1/4" thick), and cut to fit each window. We'd cover all but the windows under the awning. We'd also paint and insulate the skylights, as that is a major heat source in the summer. Painted the inside of the outer dome, inside of the inner dome, and filled the gap between the domes with batten insulation. We hated the skylights anyway. Of course also add the pillows in the vents. Yes, it gets darker inside, but stays very cool and works very well. We've also insulated our AC return air box on the roof, inside and out to improve efficiency of the cold air return. On most units, all you have between the 100° temp and your return air is the thin sheet metal and outer cover, so imagine the heat transfer. We full timed for a while, so you tend to learn what works and what doesn't over time to maintain comfort. With all of the above done, we had no problem maintaining cool temps in the summer.

I think you're heading in the right direction with your ideas. Please post any pictures of the progress if you can.

[newbold1]

Thank you for your reply and comments.

Yes, I figured and found it to be true that some water will need to be in the tanks for the heat pads to be effective. I just don't plan to let the tanks fill up to the max capacity. I do have the exterior dump valves and yes I have had those to slightly freeze up when everything else was fine. I found that running some hot water into the tanks thawed the drain lines enough but yes, I do want to come up with a better / safer solution for that area. I assume it needs to be wrapped in some way but I am not sure with what just yet and how to make it a permanent fix. Heat tape with some sort of large diameter pipe insulation perhaps? I need to look into it further but figured that might be the last area I tackle.

For the cooling issue, the windows definitely have proven to be the biggest issue. I have some of that reflective bubble insulation and have used it on the windows facing the sun and that helps. I have also used one of those vent/fan pillow things to insulate that area in the bathroom as well. All in all, I was surprised at how well my A/C was able to keep up given the lack of good insulation in my RV. Since I was able to maintain... barely... 72 degrees inside when it was 95 degrees outside and blazing sun then all I am looking for is just a few more degrees of capability and I will be in pretty good shape for hot weather camping. Most of the time its fine already... just not so much in the extreme heat and extreme sun. I am very glad I got the 15K option rather than the 13.5K A/C. Otherwise, I don't think we would be able to be comfortable in hot weather.

Mostly though I am looking for added cold weather protection since I like to continue camping in the winter. I am constantly winterizing / de-winterizing... which is fine. I just worry that while camping I could end up with some water line / tank damage due to freezing and I want to do what I can to prevent it. I am very curious to see what all is inside that underbelly once I remove the covering. I hope that the slide tracks are not going to be a big problem for getting insulation in there without interfering with the slides. I am guessing I will end up with some insulation gaps due to having to leave a clear path for the slide tracks. Until I see in there for the first time I am not sure what I will need to do in order to secure the insulation such that it doesn't shift and get hung up in those tracks. Hopefully, I will look in there and see a simple solution for that issue.

Being in the Nashville, TN area, it certainly reaches down to the 20s but not much lower and not for any sustained amount of time. A low of 10 degrees for periods of a few hours and 20-25 degrees for a duration of 2-3 days is about as extreme as I will likely ever experience in the RV. If I can get the trailer insulated enough to handle that without damaging it then my primary objective will have been accomplished.

[BigJohnD]

I don't think you'll have an issue with the slide tracks if it's the typical lippert twin rail type. I haven't pulled our underbelly down yet, but need to get it down just to satisfy my curiosity, and rearrange the fresh water tank plumbing.

[snowbird47]

I do not know if you have had this experience, but when we "cold camped" late last month (not by choice, we were heading South for the Winter) and the temps were consistently freezing or below, our Norcold fridge would not cool, either on propane or AC. I think it just cannot overcome that cold in order to heat the ammonia fluid.

It worked fine once we got to warmer climes.

[newbold1]

I have heard people say this about the fridge. I haven't had it happen to me so far and I also have the Norcold fridge. I have heard that there is some sort of add-on thing for making the fridge functional in the extreme cold. I assume finding a way to get some heat behind the fridge would work but how to do so safely... I'm unsure.

[ctbailey]

Ive got the Norcold fridge too... although I can't speak to the non-cooling in cold temps issue... I've got something as food for thought:

Our unit has a pantry cupboard immediately adjacent to the fridge. When I stick my head into the pantry and look up into the ceiling of the pantry... I see daylight!

Apparently, the pantry cupboard paneling is the EXTERIOR paneling which makes up the fridge compartment. When I am looking up at the corner of the pantry wall/ceiling, I am seeing daylight from the fridge vent cap.

This means that the fridge vent cap in my unit allows the pantry paneling to be exposed to "atmospheric" conditions.

This doesn't exactly sit well with me, but my only option is to:
a) complain to the dealer that I don't like this
or
b) pull down the paneling and have a look-see to see if any rain/snow can get into the walls through the fridge vent.

Why do I bring this up in this thread? Well - you might have a similar situation, and be able to mod your pantry to send some heat to the rear of your fridge.

[myers509]

Has anyone tried to make a Swift SLX Baja all weather? We live in Colorado and would love to continue to camp into the cold weather months. Even in fall and spring, the nights can dip below freezing in the mountains, so we would like to look into the option to modify the camper to make it more like the thermal package. I know that we could move up in model, but we want to stick with the ultra light camper. Any advice would be appreciated!

[BigJohnD]

ctbailey, we've noticed that in a majority of our rigs. Foam board, small framing and a new panel on top (Making an insulated sandwich), plus seal at the top of at panel. Not always possible, but we've achieved blocking that bit of air flow most of the time.

[ctbailey]

Originally Posted by BigJohnD

ctbailey, we've noticed that in a majority of our rigs. Foam board, small framing and a new panel on top (Making an insulated sandwich), plus seal at the top of at panel. Not always possible, but we've achieved blocking that bit of air flow most of the time.

That sounds like it would work. Basically you're making the walls and inch and a half thicker, right?

[ctbailey]

Originally Posted by myers509

Has anyone tried to make a Swift SLX Baja all weather? We live in Colorado and would love to continue to camp into the cold weather months. Even in fall and spring, the nights can dip below freezing in the mountains, so we would like to look into the option to modify the camper to make it more like the thermal package. I know that we could move up in model, but we want to stick with the ultra light camper. Any advice would be appreciated!

The new PEX plumbing is mugh more forgiving than the old generation plumbing. A quick weekend usually won't wreck things If temps dip into the low 30's for a couple hours.

It's sitting in the yard all winter at well sub freezing that up u need to worry.

And, like Someine mentioned, you can de/re winterize anytime.

Running the heater, opening the cabinets to the plumbing will help.

Heated tanks will keep the poo warm, but what you really need is a heated dump valve, THATS something you don't want to freeze.

Then, you've got to figure out who still has a dump station open. Chances are no one will have any tuning water at the dump station, so if you "need" to back flush ( a relatively new phenomenon) you might have to wait till spring.

It can be done, but it takes planning. Retrofitting a trailer into a four season trailer will be a lot of work and money.

[BigJohnD]

Pretty much just 1" or so. Kind of up to you and also determined by what space you have to work with. Figure the existing paneling is 1/8", plus the 3/4" foam board, plus the 1/4 or 1/8" paneling you use.

[hozerdude]

Originally Posted by newbold1

I have a 2013 Jayco White Hawk 30DSRE which has an enclosed underbelly but was not advertised as all weather or climate shield.

I plan to add R19 vapor barrier insulation to the entire bottom of the trailer (except where the slide bars might catch the insulation) and I am also adding holding tank heat pads to the fresh, grey, and black tanks. I will be encapsulating any water lines I see in R3 pipe insulation.

Has anyone else done this and if so what can I realistically expect?

I have already done a bit of camping in 20 degree weather and haven't had any issues so far. The floor gets cold but the pipes didn't freeze. I am wondering if these modifications might allow me to handle sustained temperatures in the 10-20 degree range.

Also, in the summer, will the added insulation to the floor make any difference in being able to retain more of the cold air from the A/C? I have the 15K unit and it does a pretty good job. It only struggles when the outside temperature is about 95 or above and the trailer is not in any shade. Then, it can barely get to 72 degrees inside the trailer and takes a long time to recover if someone opens the exterior door. Could I expect that this might improve a little with the added floor insulation?

I'm just anxious to get this done and in the meantime am hoping to hear other people's experience with this sort of modification.

It was a pain in the ass to remove all the screws on my underbelly on my 38 ft. 341 RLQS but I put R30 insulation ( 8" thick ) only cost me $14 a roll at Home Depot. I bought 2 rolls. Glad I did since I live in my 5'er here in Colorado. Big difference in the winter and save on propane. I also put R13 all over in my basment and Generator box

[newbold1]

Originally Posted by ctbailey

Ive got the Norcold fridge too... although I can't speak to the non-cooling in cold temps issue... I've got something as food for thought:

Our unit has a pantry cupboard immediately adjacent to the fridge. When I stick my head into the pantry and look up into the ceiling of the pantry... I see daylight!

Apparently, the pantry cupboard paneling is the EXTERIOR paneling which makes up the fridge compartment. When I am looking up at the corner of the pantry wall/ceiling, I am seeing daylight from the fridge vent cap.

This means that the fridge vent cap in my unit allows the pantry paneling to be exposed to "atmospheric" conditions.

This doesn't exactly sit well with me, but my only option is to:
a) complain to the dealer that I don't like this
or
b) pull down the paneling and have a look-see to see if any rain/snow can get into the walls through the fridge vent.

Why do I bring this up in this thread? Well - you might have a similar situation, and be able to mod your pantry to send some heat to the rear of your fridge.

Mine doesn't have that sort of exposure. Pantry is on the other side of the RV and next to my fridge is counter space and then the stove. In mine, the fridge is sort of self contained. However, I can see how the access panels underneath could provide a way to get some warmer air directed in that compartment. When I get all these other things done I will probably be looking into that as well.

[newbold1]

I am actually enjoying the process of doing the work to "upgrade" my trailer to make it more cold weather capable.

My grey tank pipe is long and exposed and of course the dump valve for grey / black is exposed as well. I bought a 30' long heat tape which I think I will wrap spirally down the length of the grey pipe and the dump valve. Then, I will use two pieces of 1 inch foam pipe insulation (R3) to encapsulate the pipe and heat tape. Basically need to use two in order to make it wrap around that large circumference. Using zip ties every 12 inches or so along the pipe I should be able to make a fairly sturdy "permanent" insulated set-up under there.

I will be running power to a weather proof 4-gang outlet box under the RV in order to plug in all three heat pads to AC power. I will use the 4th outlet for the heat tape. All four outlets will be on separate switches that will be in weather proof boxes near the battery compartment. There will be additional switches in that area for the three heat pads DC connection to the battery with a 15 amp fuse between each of those lines.

If the weather wasn't so nasty and the days so short I would be getting this done ASAP. But, I think I will wait until January when i am going to be in central Florida for a week. The work should be easier to do there.

[TCNashville]

Please post pictures as you go along. Thinking of doing something similar.

[newbold1]

Well... the job is done. When I started I attempted to record with video / photos but found that everything I wanted to show couldn't be seen because it was far too dark under the trailer. Trying to juggle a camera, a flashlight, a drill, screws, wires, and everything while laying on my back just wasn't working out.

Anyway, the task was about twice as difficult and time consuming as I had expected. One big issue is that once you pull down some of the underbelly covering, it is nearly impossible to line it back up such that you can find the right places to screw it back into the cross bars. I was very nervous about drilling a screw into something other than those bars and doing some sort of damage to a water line, heater line, electrical line, etc.

Getting into the underbelly was difficult. The covering had a million screws to remove. Plus there are pipes and lines coming through it that prevent you from really just taking the whole thing off in a big piece. There were places that I had no choice but to cut and once cut there wasn't a really good way to repair the cut.

Once inside, attaching the heating pads to the tanks was pretty easy. The only problem was that the tanks moist with condensation and drying with a towel wasn't working. This made it difficult to get the heat pads to stick to the surface. It worked, but could have been better. Running the power lines was pretty easy. I attached outlets to the outer frame I-beam which were then hidden by the aluminum trim that runs along the bottom sides of the trailer. I plugged the heat pad cords into those outlets and tucked all the extra wire length up inside the underbelly. I used a heat tape on the long grey water pipe that is exposed under the underbelly covering. I wrapped it around the pipe in a spiral and then wrapped that with R3 pipe insulation tubes which I zip tied into place. I plugged that into one of my new outlets. So... two outlet boxes with two outlets in each which took care of the three heat pads and one heat tape.

At the front of the trailer I mounted to the frame a weather proof box that contains a switch to turn on the four outlets. I changed my mind and decided there really was no need for all that extra wiring to turn on/off each thing one by one. If I am going to have it on then really I will have it all on so one switch was fine. I added a second switch for DC. I ran a second set of power lines for the DC power to the three heat pads. That's all done except for the connection of that switch to the battery itself. I need to get a bus bar on the batter to make a good connection so I will do that at a later time. Should be pretty easy... just need the parts.

In order to get AC power supplied to my switch that feeds those outlets for the heat pads I tapped into the outlet that is behind the mini fridge in my storage compartment. This required cutting the wires off of the existing outlet box. That outlet box ended up thrown out as they seem to not be reusable. I put in a new box, wire nutted the wires together, and installed a new residential style outlet for the mini fridge. Then, that gave me a new feed wire to run under the trailer to my new weather proof switch box.

At this point, all the electrical was done and the components installed. It was time to stuff the underbelly with the R19 insulation. At the rear of the trailer this was a pretty easy job. That section is mostly hollow with nothing much up under there to get in the way. It was more difficult around the axles due to the crowded work space but also because that's where I had the holding tanks, a lot of electrical lines, plumbing, etc. all in the way. I stuffed what I could under there but the holding tanks pretty much take up 90% of that space. Forward from there was again a pretty easy job for stuffing in the insulation.

Once the insulation was all done I needed to seal up the bottom again. This was the hardest part. Whatever that corrugated plastic board is that they use for the underbelly... I don't have any of that laying around. If so, I could have just cut large pieces to cover over the cut sections like a giant patch. Since I could not find that stuff anywhere I ended up going to a hardware store and bought some giant sheets of this heavy gauge plastic wall backer sort of stuff. I cut big pieces and used it to cover over the cut sections. I used some screws to attach this stuff to the corrugated covering. This was just to temporarily hold it all in place. Meanwhile, the underbelly was sagging and such because nothing was really holding it up yet except for things that protrude through it to the outside that just sort of held those areas up. The solution for making the underbelly cover strong and secure was that I bought several lengths of 1/2" deck boards for decking. I cut those to the exact side to side length of the trailer frame. Then, I slipped one end of the board on the lip of the I-beam to hold it up, went to the other side, and at an angle managed to wedge the other side of the board onto the lip of the other I-beam. Then, used a rubber mallet to whack it into place making a straight cross member holding up the corrugated underbelly cover. I did this every 5 feet or so. This made for a really strong underbelly and that helped to prevent the added weight of the R19 insulation from making the underbelly sag. Once these were in place they also held my new heavy gauge plastic sheets up that were covering the cut areas. I then drilled some small holes into the I-beam lips through the deck boards and put in some screws. That way, I can be assured that these will not jar there way loose at some point when traveling.

Frankly, I have no idea why Jayco didn't just put in cross members under the underbelly covering. Instead, to support the middle area they had it screwed into metal cross members that are behind the underbelly cover. But, you can't see them since they are covered and so trying to do that was just not working out very well. I thought I would be able to just use the existing holes but when all that insulation is put in there and you work this stuff into place it turns out it is virtually impossible to get those original screw holes to line up to anything. The deck board cross members were much easier and now instead of the underbelly covering hanging and held up only by screws it now has big fat beams under it holding it up. I don't think it's going anywhere.

Sorry for the long post but I wanted to try to be thorough. While I didn't get pictures of the work in progress I should be able to get some pictures of the end result. I will try to get on this ASAP to post them here.

[newbold1]

From a functional stand point...

We have had some weather consistently below freezing for the past several days. I have had the trailer connected to 30 amp power and had my new pads and heat tape turned on. After a few days I pulled the grey tank release slightly just to see if the water would come out freely... no ice. Sure enough, it not only came out but it was warm and steamed a little when it hit the cold air. I was excited to see the work seems to have paid off.

Inside the trailer I have noticed that I can keep the temperature warm... even hot... just using a space heater set on high (1,500 watts). I don't have to run the propane heat at all even on a ~25 degree day. The floors are no longer really cold but seem just cool which is an improvement.

Something I did not expect at all is that the bedroom which sits over the storage bay is no longer drafty and cold. I wasn't expecting that because while I did insulate under the storage bay... the bay itself is still a big hollow area under the bedroom that isn't climate controlled. So, I figured the bedroom would continue to suffer in cold weather. However, it seems just about as improved as the rest of the trailer. My wife thinks maybe the insulation is keeping some cold air from getting into the front cap wall and edges which is where it seemed the coldest. Maybe she is right.

I will be very curious how the plumbing and temperature retention works when we next camp in really cold weather. I wonder just how cold I can go now without having to worry about freezing damage. I am thinking I might be good down to around 10 degrees now. Maybe even between 0-10 degrees. That's more than I need because the 20s is about as cold as we deal with here.