What defines a TT as a "True Four Season"?

jungleexplorer wrote:

Fireballsocal wrote:
None that I know of. Possibly in Australia? I camp in hot dry weather. The hottest last year was 113F and I have been out sans RV in 119. In 113, the air con in the RV can't keep up, even in my little lance, and the RV slowly heats up, though this trailer seems to perform the best in the very hot stuff.

What model of TT do you have?

2009 Lance 1880 non slide. All windows get reflectix and the skylight in the shower also.

westend wrote:

I said all this because there seems to be almost a singular focus on how well an handles the cold, and no discussion about how it handles the heat. I think this is because there is a general consensus that, if a RV designed to handle the cold well, it will also be good for the heat. While this is true to some extent, I think the complete ignorance of radiant heat, which is he main source of heat in the summer on RVs, has lead to a misunderstanding that a good cold weather RV is best for summer heat as well, and this is simply not the case.

Considering all the above information, my question then is. Are there Travel Trailers that are specifically design with a focus on use in a hot climate where there will a lot more radiant heat then conductive heat to deal with?

If you are a builder, you should know that R-factor is a resistance to the transfer of heat and cold.
One large problem with RV's is that the Mfg's skew the R- ratings by tossing in a foil bubble wrap and add the large rating number into the mix. Since the bubble wrap is never installed to meet the high rating, i.e. installed in a cavity with no convective loss, it is a marketing gimmick.

What I did with my trailer is probably not what you want to do but maybe it's insightful: I gutted the whole thing from the inside. I packed in as much extruded insulation board as I could friction fit in the cavities. From the wall cavities, I then installed a 4 mil vapor barrier. Inboard of that vapor barrier is 1/4" fanfold extruded insulation. This latter layer removes any conductive transfer through the wall studs/exterior skin. Paneling was laid across the frame and secured with finishing nails and screws. I pretty much did the whole trailer like this--wheel wells, ceiling, floor.
I also eliminated a good bit of window glass and replaced what glass is left with Low-E sliders or a stationary panel. The roof was painted with a white acrylic coating. I replaced the RV furnace with a non-electric propane heater, surrounded with masonry. The furnace is piped for combustion and make-up air in the stack.

The result of all my work is a trailer that is easy to heat and cool. If I leave windows open to catch 70f night air and close everything up in anticipation of a 90f day, the interior temps at noon will be 75f.
I haven't done a lot of Winter camping but if it is like previous trailers I've upgraded, parking in average MN Winter temps of 10f, will mean 30 lbs. of propane/wk for heating. Water heating and cooking, which vary by number of occupants (as do door openings), will add to the propane bill, maybe an additional 20 lbs/wk.

You are probably not looking for all the work of a gut out and repack. Just try to find a trailer with solid insulation, thermal windows, and an efficient air conditioner/heat pump. Using some type of shade cloth in Summer and skirting in the Winter will add a lot of comfortability.

That is quite amazing what you did with you rv. I wonder why no RV maker ever thought of making an RV with 3 inch thick walls (BOOM! Mind blown!). I am sure full timers would gladly give up two inches of width to effectively double the R-value of their TT. I know I would.

Here is my dilemma. I want an Arctic Fox, but Northwood does not make it in the floor plan I want (Bunkhouse model that sleeps 7+). The only Nash model that has the floor plan I want (29S) just came out and I can't afford it. The Outdoors RV model I want (27bhs) is rarer then ice cubes in the Mojave and I can't find one for sale within a thousand miles of me and I have traveled across four dang states (Texas, New Mexico, Arizona and California) trying to find one.

Bottom line, I am looking for alternate brands that might fit my needs. I am so tired of looking at models that are designed for singles or couples with no kids it makes me sick. It's like no one in this country wants or cares about family anymore. I was even thrown out of a couple RV parks I pulled into in Phoenix because I had my 15 year old son with me. I have never seen such hatred for families and was completely unaware that such places existed. The look on those old bags faces when I told them I needed a spot for the night for me, my wife and my son, was unbelievable. You would have thought I had just told them that I had the Bubonic plague. After I was turned away by the third place, I just asked the next place right out, "Do you hate kids too?" I finally did find a run down RV park in Phoenix that did take kids, but I was starting to wonder if I ever would.

What astounds me more then an RV park that has an age limit, is the thousands of grandparents that live in those places that hate their own grand kids and want nothing to do with them. There is not a single person in my family for the last five generations that would ever consider living in such a place where they could not have their kids and grand kids stay with them. We actually love our family and want to spend time with them. But I guess my family is unique, because there sure were a lot of old people in those parks. It blows my mind, but since the overwhelming majority of RVs are designed for people with that mentality (Especially Arctic Foxes), I guess I am the abnormal one here. What has this country come to? Okay. Off my soap box now. LOL!

Most TTs use open cell insulation in the walls of fiberglass side units. That has an R-value of about 3.6 per inch so if your walls are only an inch thick, that's not much insulation. Outdoors RV states their walls are 2" thick but if they use open cell insulation, the wall R-value would be about 8 which still isn't that great. If Outdoors RV used closed cell insulation, they could get an R-value of about 14 which would be way better than the typical TT. Can't see where OR states what type of insulation they use.

Our KZ TT has a fiberglass exterior but only the side walls have foam and the front and rear have batt insulation.

Some TTs (like ours) use Reflectix blankets to supposedly increase the R-value but from what I've read, the jury is still out on whether they actually help much. I don't think it does much for us and they would have done better by insulating the ceiling correctly.

TTs aren't built right in terms of a moisture retarder/vapor barrier. With open cell insulation moisture migrates to the exterior skin in cold temps and will condense, leading to rot, corrosion and delamination. If they were to use the closed cell, that prevents moisture from migrating through it. A house usually has a type of insulation that does not stop moisture migration but there is a barrier on the interior side of the wall (sheet plastic) that a TT does not have.

Outdoors RV units have two or three layers of batt insulation in a ceiling. That is good, but it depends on how it is installed. If it is compressed at all, it loses it's R-value. And if moisture is allowed into it, the R-value also drops. So unless they have a vapor barrier on the underside of the insulation, I think the actual R-value will be less than stated.

In our TT, we have an arched ceiling and there is no batt insulation around the entire perimeter about 6" inward because there is too little space to install any. As well, there are many voids and in many locations, gaps because of wiring laying across the joists. With the greatest heat loss being in a ceiling, I would guess that the insulation in most or all TTs is poor.

In cold weather, you can have the best insulation possible but you must vent out the moisture laden air by opening a window(s) and running a roof fan and/or using a dehumidifier. Some will even seal up every opening possible, including the weep holes in windows in an attempt to retain heat and reduce propane consumption. Big mistake. The average adult human body gives off around 2 pints or more of water per day depending on activity level, plus you've got moisture from showering and cooking. That's a lot of water to expel to the outside and if you don't will lead to damage to the structure. I read of one case where a person was staying in a FW over the winter in Seattle and water was raining down on him from the ceiling from a failure to expel moisture laden air.

Many enclosed underbellies heat the space from a couple of ducts off the furnace which is very inefficient. I'd look for a TT that has heating blankets under the tanks and better insulation in the floor instead or even do that yourself.

If you have shore power available, I would consider electric heating over a furnace if the TT has good insulation. We run our TT on 2,000 watts total of 3 permanently mounted heaters on 30 amps and it works well down to near freezing for our 29' unit (overall).

Outdoors may be ahead of the pack on 4-season TTs but could still be less than technically possible and desirable. Overall, their units are much better built & designed than most of the rest tho.

I said all this because there seems to be almost a singular focus on how well an handles the cold, and no discussion about how it handles the heat. I think this is because there is a general consensus that, if a RV designed to handle the cold well, it will also be good for the heat. While this is true to some extent, I think the complete ignorance of radiant heat, which is he main source of heat in the summer on RVs, has lead to a misunderstanding that a good cold weather RV is best for summer heat as well, and this is simply not the case.

Considering all the above information, my question then is. Are there Travel Trailers that are specifically design with a focus on use in a hot climate where there will a lot more radiant heat then conductive heat to deal with?

If you are a builder, you should know that R-factor is a resistance to the transfer of heat and cold.
One large problem with RV's is that the Mfg's skew the R- ratings by tossing in a foil bubble wrap and add the large rating number into the mix. Since the bubble wrap is never installed to meet the high rating, i.e. installed in a cavity with no convective loss, it is a marketing gimmick.

What I did with my trailer is probably not what you want to do but maybe it's insightful: I gutted the whole thing from the inside. I packed in as much extruded insulation board as I could friction fit in the cavities. From the wall cavities, I then installed a 4 mil vapor barrier. Inboard of that vapor barrier is 1/4" fanfold extruded insulation. This latter layer removes any conductive transfer through the wall studs/exterior skin. Paneling was laid across the frame and secured with finishing nails and screws. I pretty much did the whole trailer like this--wheel wells, ceiling, floor.
I also eliminated a good bit of window glass and replaced what glass is left with Low-E sliders or a stationary panel. The roof was painted with a white acrylic coating. I replaced the RV furnace with a non-electric propane heater, surrounded with masonry. The furnace is piped for combustion and make-up air in the stack.

The result of all my work is a trailer that is easy to heat and cool. If I leave windows open to catch 70f night air and close everything up in anticipation of a 90f day, the interior temps at noon will be 75f.
I haven't done a lot of Winter camping but if it is like previous trailers I've upgraded, parking in average MN Winter temps of 10f, will mean 30 lbs. of propane/wk for heating. Water heating and cooking, which vary by number of occupants (as do door openings), will add to the propane bill, maybe an additional 20 lbs/wk.

You are probably not looking for all the work of a gut out and repack. Just try to find a trailer with solid insulation, thermal windows, and an efficient air conditioner/heat pump. Using some type of shade cloth in Summer and skirting in the Winter will add a lot of comfortability.

Fireballsocal wrote:
None that I know of. Possibly in Australia? I camp in hot dry weather. The hottest last year was 113F and I have been out sans RV in 119. In 113, the air con in the RV can't keep up, even in my little lance, and the RV slowly heats up, though this trailer seems to perform the best in the very hot stuff.

What model of TT do you have?

None that I know of. Possibly in Australia? I camp in hot dry weather. The hottest last year was 113F and I have been out sans RV in 119. In 113, the air con in the RV can't keep up, even in my little lance, and the RV slowly heats up, though this trailer seems to perform the best in the very hot stuff.

Okay, although I would like a TT that is good for cold, heat is my main concern. Now, one would assume that what is good for the cold will be good for the heat, but that is not completely true. Where as an RV designed for the cold is designed to keep the heat in, a summer RV should be designed to keep the heat out.

The two main types of heat that an RV has to deal with, is Radiant heat and Conductive heat. R values only slow down Conductive Heat, this is why they work well for helping keep the conductive heat from the furnace in an RV during the winter.

Heat is energy just like electricity. And just like electricity, in which certain materials (like aluminum and copper) have a lower resistance then rubber and are better at conducting electrical energy; some materials (like rubber that resist conduction of electrical current) also resist the conduction of heat energy. Although no material can completely stop the conduction of heat energy, some materials with an R value (like wood, foam and fiberglass) slow down the conduction of heat energy.

In the winter time, it gets colder because there is less sunlight. All heat from the sun is Radiant heat. Just like you can't feel the conductive heat from a camp fire on a cold night if you stand far away from it, we can't feel the conductive heat from the sun that is 93 million miles away. What we get from the sun is Radiant heat that heats up the materials it touches and then we feel the conductive heat from those materials. To better understand this concept, try to go into a greenhouse in the middle of the winter on a bright sunny day. I have a a greenhouse and even though the walls are made out of plastic (which has no insulating value), it can be 20 degrees outside, but will be 60 degrees in my greenhouse during a sunny day, with no other heat source. This is the power of radiant heat.

Okay, so what does this have to do with RVs. Well, in the summer time the biggest heat source that an RV has to deal with is Radiant heat from the sun, not conductive heat. Where as a trailer with a good R value will help slow down radiant heat, it will do a more poorer job of keeping radiant heat out during the summer, then conductive heat in during the winter. So while, a good winter RV will be better for summer too, it is not the best it can be when it comes to summer heat because the focus of the construction for a winter RV is Conductive heat and not Radiant heat.

While an RV built for hotter climates should certainly provide good resistance to conductive heat, it must additionally focus is on reflecting Radiant heat.



I said all this because there seems to be almost a singular focus on how well an handles the cold, and no discussion about how it handles the heat. I think this is because there is a general consensus that, if a RV designed to handle the cold well, it will also be good for the heat. While this is true to some extent, I think the complete ignorance of radiant heat, which is he main source of heat in the summer on RVs, has lead to a misunderstanding that a good cold weather RV is best for summer heat as well, and this is simply not the case.

Considering all the above information, my question then is. Are there Travel Trailers that are specifically design with a focus on use in a hot climate where there will a lot more radiant heat then conductive heat to deal with?

...

Okay, so it seems that there are no clear definitions for what constitutes a "True four season" TT. I understand that you can only get so much R value out of a 2" thick wall, no matter what is inside it.

Here is a statement about the construction of an Outdoors RV TT (All models). This comes from a email conversation I had with an OR rep. I am just wondering if this is common construction among all TT brands, or is it superior to most?

"There are two layers of R7 fiberglass insulation in the roof as well as an R-15 Astro foil blanket. That is duplicated in the underbelly. We have an R7 in all of our walls including all walls in the slide out"


I currently am on the road in a Jayco Swift SLX. We have been traveling through the southern part of the US from Texas to California. All I can say is that, I am convinced this Jayco is made out of toothpicks and tinfoil. It is absolutely worthless at any temperature other then 70 degrees in the shade. I thought we were going to die in Phoenix, AZ. We are up near Yosemite now and the temps are decent during the day, but as soon as the sun hits this thing, it's like being in an oven and the AC is completely useless.

I am a builder and understand insulation, so I am not expecting a miracle that defies the laws of physics. What I am trying to figure out though is, which brands are truly better. For instance, I went to an RV center and looked at a Heartland Mallard. Asked the salesman about the insulation. He made the same claims that that the OR rep did, and that is the problem; no salesman is going to run down their own product. So how do you really know if one us built better then the other?

I have lived in the winter in Texas in a couple RVs, and both blew through propane like water and you were still freezing inside. But I read an article about a guy whole spent a week in his rv at 18 degrees and claimed he was toasty warm and his 7lb propane cylinder lasted 5 days. I have never owned an RV that I could claim this about. All RVs I have ever used, were useless at temps other then 50 to 80 degrees. Anything outside that and the AC or the heater could not keep up.

I live in central Texas. It is mostly hot there, but we do get some low temps during the winter in the lower teens in January and February. If I could find a TT that would handle these temps "reasonably" well, then I would consider that to be a four season TT for me. I am not looking to spend the winter in Antarctica at -200 below zero.

My current prospects are Outdoors RVs. I have eliminated the Arctic Fox because they are designed for people who hate kids and want to live alone, as they do not have a single Bunkhouse model available (Frustration her because I would like to have an Arctic Fox). But I am striking out at finding a bunkhouse model of Outdoors RV for sale in my price range (I have looked in Texas, New Mexico, Arizona and California). So, if there are other brands out there I should be looking at, then I would appreciate the name.

rbpru wrote:
The two questions I have are, what temps are these four season units designed for and how many tanks of LP would you burn through in a week of camping while snowmobiling or skiing?

Certainly if one expects to routinely venture into temps above or below the norm, I four season TT should be considered. Defining a "true" 4 season is not so easy.

Good luck

This is what NUWA had to say about '4 season'

NuWa was the first fifth wheel manufacturer to test our product in the Dometic Environmental Chamber, which subjects the coach to Zero degree cold and well over one hundred degree heat. In both instances of tests the NuWa 5th wheel kept the interior at very comfortable levels and proved that the HitchHiker is truly a 4 season product.

Now I grant you when we were in that -19*F temps we went thru a lot of propane. (Course the S&B I lived in in WY during winters went thru LOTS of propane too.)
Others in the park 'froze' ----tanks, water lines, valves etc. We STAYED roasty-toasty.

Cold temps....down to 10*F or so a 30# would last a week BUT that wasn't all furnace it was also water heater, fridge and stove/oven usage