Cargo Trailer Conversion

Looking at converting a new or used cargo trailer to a simple camping trailer and looking for some feedback and ideas.

The reasons I have for converting a cargo trailer instead of purchasing a new camper trailer are:

1) Cost: A new 7' x 14' cargo trailer starts at about $4800.00. A new 14' camper trailer up here starts around $14,000.00 depending on features.

2) Customization: When buying a new camper trailer, there are very few options that can be ordered and any customization is done at the factory and the costs can be prohibitive. With a cargo trailer conversion, the customization is endless to our needs and specs...more on this below.

3) Durability: Over the last 2 months, I have researched extensively and also looked first hand at so many new and used camper trailers and to quite frank, most are junk construction from the frame up to the shell and materials in the trailer itself and I cannot see these trailers lasting off-road based on my last experience with a regular camper trailer. Then again, maybe I am being too fussy...

As for the cargo trailers, there are a few local manufacturers and had the chance to visit 2 of them where I was invited into their shop to see trailers under construction. I was impressed with both the quality and workmanship on each visit. Even though the quality is much better, I know that even a cargo type trailer has it's limits but in my thinking will outlast a normal camper trailer regardless.

Based on the 3 above reasons, I have come to the tentative conclusion that for our requirements, a conversion is the way to proceed.

If we go ahead and order a cargo trailer it would be built with the following which adds roughly $700.00 to the base cost above: $700.00 + 4800.000 = $5500.00.

Customizations from the trailer manufacturer:

- Window in side access door
- 2 windows on each side of the trailer wall (depends on final interior plans but at least one wall will have a window.)
- Extra ceiling vent above side access door
- Dual propane tank mount on front bumper

- Canoe/Kayak rack on trailer roof (final cost has not been determined yet.)

Interior plans for the trailer has a $3000.00 to 4000.00 budget to start with for this year.

The idea of the trailer is to be used as a base for on and off-road traveling/camping/hiking/fishing (8 weeks vacation starting next year + weekends, stat holidays etc). We are not the type of people who like creature comforts so the interior does not need to be grandeur, rather simplistic and workable without us being fearful of anything being damaged.

- The trailer would be delivered stripped on the inside. Wiring for 12 volt lights would be installed along with any plumbing once we have a final idea of what the layout will be. The interior of the trailer will then be insulated with spray foam insulation (the same type as used in houses). After the foam insulation, fiberglass reinforced paneling instead of plywood will be in installed.

We have a few ideas that we have been kicking around for interior plans and I am looking for some feedback. Note that I have visited many trailer websites already to get some ideas but still have not come to a conclusion on much yet.

I plan to do as much work of the work myself(previous background in construction, mechanical, electrical.) However I am not adverse to farming work out to pros if means getting the work done correctly and right the first time.

Working with the confines of this budget, what ideas could you come up with for this trailer. Remember no grandeur (no TV, air conditioning etc,) rather functional and simple works best but this does not mean ugly unpainted wood, shoddy workmanship etc. That said, it does not preclude small propane fridge, potable propane stove (think bigger Coleman style), 12 volt wiring / lighting etc as mentioned above.

This short YouTube video gives you an idea of what we are thinking of. One note on this particular trailer, there is a lot of wasted space.


7'x14' trailer interior. Dimensions: 6'9 wide x 14'5 long x 6'8 high.



7'x14' trailer exterior

Sounds like a great plan. A section of the Teardrops & Tiny Travel Trailers forum is devoted to cargo conversions:

http://www.mikenchell.com/forums/viewforum.php?f=42&sid=d1c1bd9f7933d6ebc7c743071cc6ab96


Good luck! Am looking forward to seeing pics of the final product.

FYI, there are some very NICELY made aluminum framed enclosed cargo trailers out there. I build furniture and have TONS of friends with cargo trailers and the aluminum ones last indefinitely, the other wear out fairly fast with constant use .

Ironwood

My cousin made one like that, you can see it a little here


They found out that they did need AC as it works like an oven in the sun, so you need to insulate it well.
They covered the inside in plywood like normal then hinged another sheet of plywood to fold up on the side so they could haul their 4 wheeler or fold it down for the bed.

It doesn't handle real well off paved roads though, not a lot of ground clearance, have to spot and go slot a lot to look for the hitch or rear to drag. Thats what steered me away from a trailer to a truck camper.

Thanks Dagny, I was on the Teardrops forum previously and did not notice this. I have also spent lot of time on the Expedition Portal forums lately. There are some nice trucks and trailers that range from home brew to the sky is the limit...

Where does your cousin generally live/travel? Up here in Canada we don't get the real hot temps like down there. Nonetheless it will be interesting to see how hot the interior can get even with the spray foam insulation.

As for the ground clearance. That is somewhat of a concern especially with the 7x14 trailers which are all dual axles. If we step down to a 6x12 sized trailer, most have a single axle which have several more inches of ground clearance depending on trailer model. Slightly bigger tires can also be added to help and the rear overhang is less.

The trade offs with a 6x12 is namely weight capacity which is generally around 1500 - 1600 lbs with a total 3000 lb GVW. Also the loss of the foot (7' vs 6') means that plans for a bed across the back of the trailer are gone as most trailers in the 6x12 size have interior width dimensions of 5'9" which is narrower in width then I am tall.

I once knew someone with limited space for his family's mobile vacation getaway, so he found a way to secure a mattress to the ceiling, and lowered it (I think it was winched, but what about other methods?) for some floor sleeping.

I'm not saying it's a great idea, but it's better than a bed taking up the floor all the time, at least to some extent.

http://cheapgreenrvliving.com/Converted_Cargo_Trailer.html

Thought about that also. For 2 adults, a queen sized bed ("80x60") is needed as a double (75"x54") is just too small for more then 1 or 2 nights of crowded sleep.

With the queen mattress being that size, there is not a lot of maneuver room to be winching a mattress up/down from the ceiling etc. The original plan with the 7x14 trailer was to have the mattress across the back and 2' off the floor with the space underneath used as storage.

Anyone have any other ideas?

Thanks, seen that website before. The interior design of the trailer is too "rustic" and made me feel claustrophobic as it is so crowded in there!

If there's room, you can make a "closet bed" / "Murphy bed". Essentially just hinge the mattress/bed to the wall and lift the other end when not in use.

Much more robust and less finicky than lifting the whole thing up under the roof.

If there's a folding bed variant that suits your needs (sleeping comfort, size etc) then that may also be a space saving alternative.

You might try to find an ambulance body off a dually van/truck. They vary in size but average ones are 12' long, SUPER strong alloy aluminum extrusion welded joints and well insulated. I found one lightly rolled, awsome find for $400, I talked to a few guys who scrap the older aluminum ones and they said it is hard to crush them with a trackhoe. It is skinned in 1/8" aluminum. The one I have is a Lifeline type I or II (dont remember) but I would bet it would cost 40k just for the rear body new. As a bonus there was a bunch of electricals left in it. You could then use tires and axles of your chosing, I am using 17.5" singles good for 6000lbs each on a custom frame.


http://www.lifelineambulance.com/products.html
Ironwood

WV and MD, they didn't put any insulation so the aluminum conducted the heat and it got sort of a greenhouse effect even with the roof vent open.
I thought that if they would put a small window in the bottom of the side door to draw in cool air and let it circulate it would help.
it would also get very cold at night, again the aluminum conducting the heat.
I'd put a layer of the ping solid foam insulation then the aluminum bubble wrap stuff to reflect inside and then a strip of the foam vapor barrier stuff on the frame studs before skinning the inside with wood to isolate from the aluminum frame.
IIRC they just did a 4x8 plywood for the bed with an air mattress sitting on top so you could walk alongside the bed.

There is a guy on expedition portal who bought a u haul body then chopped the bottom off and clamped it on top the bed rails of his truck.

If I could find a place to buy 1/8" x4' x8' aluminum affordable and a bending brake big enough I drew out a design to re do my whole camper in 1/8" aluminum so the outside skin is basically the frame, like the body of a car.
But the cost is more than my budget so I'm using plywood and 1x lumber like the original.

I'd go with an inflatable mattress. Adjustable firmness and much lighter. Packs small

The trailer will be insulated with spray foam insulation which is the same type used to insulate walls in homes. I got a quote yesterday from a company and they will do the spraying for a bit more cost then purchasing rigid insulation panels. He told me it would take only 15-20 minutes to spray the trailer and whereas it would take me some hours to complete with rigid insulation panels.

Dagney provided me with a good link to another forum that has a lot of info on these type of trailer conversions and has resulted in several new ideas to contemplate including a folding bed.

What kind of off-gassing does that spray insulation produce? Does your sprayer guy know what you're going to be using it for? Have you read the Material Safety & Data Sheet on the type they're planning to use? How does heat affect the cured foam?

I googled 'spray foam insulation msds' and grabbed the first one I came across. Others may be different. Here are snippets. I don't know what they are, but some of it didn't sound so great to be closed in with.

*************************
RHH Foam Systems
VERSI-FOAM Systems I, 9, 15, 50 and 1.75 pcf Refillable - Standard Component A

SECTION 2 - CHEMICAL COMPOSITION
CHEMICAL.................... CAS #................. CONCENTRATION
Polymethylene polyphenyl.... 9016-87-9............. 80% to 100%
isocyanate
Containing 4,4 Methylene.... 101-68-8
bisphenylisocyanate (MDI)
(Approximately 40%-50% MDI)
Tetrafluoroethane (134a).....811-97-2.............. <15%

EMERGENCY OVERVIEW - Brown liquid. Slightly Musty. Sprayed or heated material harmful if inhaled. May cause allergic skin reaction. May cause allergic respiratory reaction and lung injury. Avoid temperatures above 105°F (41°C). Toxic flammable gases and heat are released under decomposition conditions. Toxic fumes may be released in fire situations. Reacts slowly with water, releasing carbon dioxide, which can cause pressure buildup and rupture of closed containers. Elevated temperatures accelerate this process.

INHALATION - At room temperature, vapors are minimal due to low vapor pressure. Excessive exposure may cause irritation of the eyes, upper respiratory tract, and pulmonary edema (fluid in lungs). May cause respiratory sensitization to susceptible individuals. MDI concentrations below the exposure guidelines may cause allergic respiratory reactions in individuals already sensitized. Symptoms may include coughing, difficult breathing and a feeling of tightness in the chest. Effects may be delayed. Decreased lung function has been associated with overexposure to isocyanates.

******************************

How does something like this compare to the sheet insulation?

Metal boxes get hot in the sun.

If you had several small intake vents along the bottom and more at the top, you could use natural convection to draw in cool air and vent the hot air.

Inflatable beds are light, but they aren't warm in cold weather. The Murphy bed probably comes closest to ideal.

Sounds like fun!

Sue

Check out this web site for some great info http://myswag.org/forum/index.php?board=28.0

You can only see photos if you register, they are very friendly there and although mostly Australians people are on there from all over. Anything built for the Aussie bush is TOUGH. Most on there are doing canvas based trailers but I'm sure there will be useful info for you