Teardrops n Tiny Travel Trailers

Dear Folks , am reconsidering the usual vent on the roof , that appears to be the accepted practice ... First you have to cut a hole in the roof .... I never liked that idea , especially here where it Rains a LOT ... Plus it adds a couple inches to the height , which may make it harder , or impossible to get in the garage ... grrrrr!!!!! Don’t know where this top vent business started , probably in the desert... We used the same ones back in the 70’s on Kustom Van conversions, and quickly learned most would leak sooner or later ...
Taking a note from the Old Timers (vintage trailers) They placed their vents on the side ...Up high , naturally ... This may be a better way , under certain circumstances... Like here... Easy to shield it from the rain , and even install a small computer fan for an exhaust effect ... and while we’re at it , a feature that might be appropriate is a small floor vent ... then you could get a natural airflow through the cabin , cool air entering through the bottom vent , hot humid air exiting the top/side ... and you could control the airflow by how much you open the bottom vent ... easy for Foamies (or anything else , and NO holes in the roof ... !!! Might fit in the Garage too ...

Ps. small screens over the openings would prevent frog, lizard and wasp entry ... my top vent is like a bug Motel ... they check in , but ... Always pulling the screen and emptying out the dead creatures... Yuck !!! still a bad design , IMHO ...

Just another humble idea for your considerations....

when my foamie was being built, they added the frame for the vent/fantastic fan up there. since then we canvased the foamie. and i have a problem with cutting thru that canvas. i just can't see doing that. i have to windows across from each other (in my doors), so far they have worked just fine for me. i know others will still want that vent and i can see it for really hot days. another reason for loving this build your own idea, build what you want and enjoy the heck out of it.

Eagle , wish I had put a side vent in my little Foamie instead... Just put the top one there out of habit ... easy enough to fill in and canvas over ...
Maybe a small full time vent is a good idea Plus the windows ... if the windows are closed, the vent is still working ... We read that sticky ...

On my first build I followed similar thinking and avoided a roof vent. However, I extended the thought to the sides as well but not due to leaks but, rather, because I felt the available vents would look ugly on the side of the tear.

I opted for the floor. My first build being all 120v I chose to mount a vent fan under the floor to draw fresh air in the windows. It worked but poorly and I found that if I wanted to cool the camper and could run the vent I would just use the A/C instead being that it was all run by 120v.

In my later builds I have opted to put vents on the roof.

Just my experience.

I was thinking of something more like this ... unobtrusive ... leaving the outer hole exposed means we can plug it (foam) for travel should that be needed ... http://content.westmarine.com/images/ca ... 183384.jpg Good size Can of the size you require with the rim cut off should make a perfect vent hole ... again , no power tools ... Save the “inner “ for the plug ...

Unfortunately my mind is rather bound by convention and when I thought of vent, I thought top vent. I went with a "fantastic vent" which is rather large and bulky and did force me to alter the roofline for garage storage. Plus there's this big (14" X 14") hole in the roof with a big bubble sticking out of it. Until recently I hadn't seen the larger size "computer" fans. If I had, I probably would have gone that route. I didn't think the fan the size of the one in my computer (about 3" in dia) would work that well. A couple of the larger ones would probably provide enough cfm flow to provide good cooling, Question.... Are there 12v versions of this or do you have to hook into 120 AC to make them work? If the fans are all 120 AC, either you camp where AC power is available (which means another "system" for some folks) or you run an inverter off your 12v. If the fantastic fan were returnable and I hadn't invested so much $$$ into it, I'd go with the "computer" fans. Just make sure you get good airflow. A little math will tell you how often you're turning over the air inside your cabin. I figure since cooling is involved the more the better but I don't know what the "standard" is.

My TD will be very small so storage isn't a concern, but I looked at several different options for venting. What I'm going to do is use a solar powered vent I purchased at West Marine. It has a low profile and also has a very small LED light built in. I'm planning on putting two PVC elbows in the sides at the rear of the trailer so I get good cross ventilation. The solar vent is used in marine applications so I think it will handle the rain without any problem. I'll know for sure shortly though. The fan itself is not a very powerful one but will run for a while without any external power source. For my build being towed behind my motorcycle I think it will work great.

From McMaster-Carr;
DC Equipment Cooling Fan
5" (127 mm) sq, 1.5" Thk, 148 CFM, 4.46" ctr-ctr bolt holes, 0.17" dia bolt holes, Wire pigtail leads, 0.82 amps, 12 VDC (also available in 24VDC, and 110VAC) PN 1939K77, $77.78

They also have accessories available like grilles and filters.

They have round ones, too. Can probably do better on the price if you shop around.

Roof vents in trailers go WAY back - one of my first childhood
memories is looking up out through them. The reason is: hot
air rises and the best exit is at the ceiling in general - ever be
in an enclosed trailer with all of the windows shut [or even with
them all open?!], out in the middle of a field, in the full sun?
Can you say "OVEN"?

A lot of the early trailers were of the 'breadloaf' design and the
ceiling/roof was the most logical place to put it - it's where the
hot air is - and the curved upper walls didn't allow placement on
the top of the side wall. In the 'canned ham' design it was still
put in the ceiling as it doesn't use any wall-space that upper
cabinets need. And it doesn't interfere with any of the rest of
the trailer's design as it is up-out-of-the-way.

One of the things that is often overlooked is to have a short
curb of sort around the perimeter of the vent opening and to
mount the vent/powered vent on that. This'll prevent rain
on the roof from just running in easily - I know there is one of
a sort included in the vent/fan body but the extra little height
of a mounting curb just would make it better.

I agree it's a better idea to not have a "hole" in the roof in general,
and for those who are height restricted, I don't see why a vent/
fan mounted as high on the side wall as possible wouldn't be a
great solution. A lot of the older trailers had a series of small vent
windows mounted high up above the regular windows near the
ceiling , which helped, but you still need a powered vent fan
to achieve the best comfort I think.

Some of the small venting ideas are interesting but the easiest
solution is still the Fantastic Fan type set up for most people.

Cheers,
Norm/mezmo

Norm , if I lived in a place that didn’t rain so much , I’d have roof vents ,moon roofs , etc . etc. Here any hole in the roof , especially on a moving vehicle (on our Bad roads) , eventually Leaks ... When it rains it RAINS... Keeping things dry here can be a real challenge when it’s not raining ... That and my Studio/Garage door is concrete... can’t open that up more without a Lot of work ...and expense...
Thing is , how much air do we have to move... Most of us are gonna’ have fans and AC, or just sit outside (if it’s not raining) .. if the weather is Nice , we’ll have the windows open.... I was thinking of this as more the requisite “Safety Vent” ... just a little vent for when you’re sleeping ...

Ps. Just thought I’d mention the old light in the piano trick ... If you keep a 40watt light bulb ( the old kind if you can find one ) burning in your cabin , it will stay dry... (Places with HIGH Humidity, like here )

Compass Rose is too large to go in our garage designed for a Model-T (it's that old), too tall and too wide. In thinking about this however there is no reason you could not design a top vent with 0 projection above or minimal rise using computer case fans. This could be as complex as installing a marine deck plate (all kinds of shapes and sizes) or make a plug of your foam. The marine deck plates are absolutely water tight. The basic is that heat rises and with fans off some heat will escape.

Our set up with the AC or heat coming in through marine deck plates in the side and you need the fans running with vent cracked above to keep the cool or heat from stratifying and keeping condensation from our breath from collecting on the walls. Our three speed computer case fans are positioned just above us in CR, most of the time are set on low speed and we find that sufficient to stay comfortable.

GPW I know this might be a little off topic but in another post you were talking about using PVC so why not put your vent fan (computer case fan) in a pipe and have it go where ever you want it to....what do you think??

Droid , Cool Idea !!! And we can cut and bend it to make our own rain deflector shield...

Speaking of vents...

Norm's curb idea is exactly how I'm mounting mine. I'm on the west coast of BC, so I'll need a vent inside year round (it rarely gets below freezing here) and need to keep lots and lots of rain out. It's done that way on boats since it not only prevents water sheeting across the deck from getting below, but it provides a horizontal surface to mount the vent to on a cambered deck (or curved TD roof...)



I'm putting together a cold air intake from the wheel well, drawn into the cabin by a squirrel cage rather than a computer fan.
I'll put the pics in my build thread.

Please excuse the expression ... COOL Vent and fan system W2 !!!