Positioning a Roof Vent/Fan?

[John61CT]

My roof rack system of choice, not cheapest but very flexible to accommodate future changes, strong and good looking.

Rhino Rack generic "RT style" tracks, get for Sprinter if you need longer than standard, can cut to length.

Yakima fits RR's tracks, so use the leg mounts for any of 4+ style crossbars, including newer low-noise profiles.

Also fittings for bikes, boats, cargo racks, spare tires etc whatever.

Make sure you get the kit for mounting the RT track on fiberglass, not rivnuts for metal. Or figure it out go to the Hardware store, not rocket science.

Get butyl rubber tape for sealing around your holes.

etrailer.com is decent pricing, great service, once you learn all the compatibility issues with patience can pick a lot up on eBay.

 

[Vagabound]

Well, those vantech roof racks for the gutter are over $200 each (per bar). They're the ones for the econoline with hightops, and I like the idea that I would not have to drill further holes into my high-top and just use the rain gutter of the van. But the price...  :-/

I have flat aluminum rails, for lack of a better term, already on the top of the box truck. They're not a roof rack, they are just part of the roof structure. I mention that because they are the perfect base for drilling holes and bolting to.

Home Depot has a metal channel product called something nifty like SuperStrut. Name doesn't show on the webpage I found. It is designed for all kinds of projects, but I have carefully looked at all the pieces and have figured out how to use it to make a roof rack. It is extremely strong and is galvanized.

Don't hold me to it, but I think all the parts and pieces and bolts to make a roof rack that would cover a 14 foot box truck cost under $200.

This is the stuff I'm talking about:

10 ft. 12-Gauge SilverGalv Electrogalvanized Slotted Strut Channnel

http://thd.co/2ccR2hM

Tom

 

[highdesertranger]

that's is uni-strut. highdesertranger

 

[John61CT]

SuperStrut is sold at HD not labeled as such until you look at the metal.

Great stuff, but for a roof rack personally I'd take less liability risk in the event of catastrophe on the road, insurance loves finding reasons not to pay.

 

[dr_nelson]

Thanks for all the input regarding a roof rack.

Man, those strutted channels from home depot are gigantic and sturdy. I checked them out because I needed wobble extensions to change the spark plugs. Home depot has them in the Electrical section, not where the common aluminum angles are.

For now, I was thinking of getting aluminum angles from e.g. buymetal.com and then create something like this for the solar panels:
(this is supposed to be the rear of the van)
[img=506x413]http://i58.photobucket.com/albums/g245/dr_nelson/Van%20Build/IMG_0036.jpg[/img]

I just realized this is actually going off-topic... sorry.

 

[Vagabound]

Happy to steer back in the direction of the thread topic ...

An item somewhat related to installing a roof fan or vent is the addition and position of a floor vent. To be clear, I'm talking about something that looks like a home heating register which just covers a rectangular hole in the floor that functions as an intake for fresh air to be provided to the roof fan.

A few questions please:

1. Generally speaking, assuming a roof fan, how crucial are floor intake vents?

2. This is a picture of the type that I'm thinking of using. Is this acceptable or is there something better to use?

http://thefrugalhomemaker.com/2012/08/13/update-your-vent-covers-with-spray-paint/

3. Where should the floor vent be located? I'm thinking about some location not near, but in relation to doors and windows to somehow maximize circulation.

4. A floor vent is going to make a pretty big hole in the floor, if I use the one I'm thinking about. Any thoughts on keeping creatures out?

Thanks,

Tom

 

[Dgorila1]

Excellent thread. I've been thinking about this exact thing myself, and just haven't taken the time to start the thread.

In my case, having a box truck, and one in which I decided to keep the roll up door. the only place the fan can go is the front half of the box somewhere. Additionally, roughly the front quarter of the box is taken up by my bed with under-bed storage.

Although I have no experience with it, I was very reluctant to put a fan over my bed, so I'm happy to read the comments from Almost There.

So, that actually leaves only the second quarter of the box roof area as a possible location for the fan. It is easy to get fooled into believing that a box truck roof would allow you nearly unlimited places to put the fan. Clearly, that isn't the case. In fact, I'm limited to a space of only four feet long by eight feet wide. And even less if other practical considerations are taken into account.

Regarding location, being already restrained longitudinally, my issue is lateral location. Simply, does it make any real difference whether I put the fan on the left side of the box, in the center, or on the right side?

----------

A related issue that I'm dealing with now regarding planning for the fan is about roof sealant. I will be putting on some white elastomeric cool roof sealant in the near future.  In my case, it is practically mandatory, and the pros and cons of all of that have been covered in another thread. 

This specific issue relates to the fact that the sealant will end up happening before the fan gets installed. My concern is having the roof sealant interfere with a later fan installation, in terms of the fan flange being able to seal properly on the roof. 

So, I've been wondering if I should just apply the sealant to my aluminum roof, ignore the future fan location, and deal with that location later, or figure out the fan location, trace it out on the roof, and carefully paint around it?

Recommendations?

Tom

Have you thought about having a sheet metal shop fabricate he one piece aluminum or stainless steel roof for you? That way it would be seam free other than any thru holes.

 

[highdesertranger]

for a floor vent I would use a deck plate like this, https://www.amazon.com/Beckson-Twis...346141&sr=8-10&keywords=deck+plate&th=1&psc=1 . that's a 6 inch they come in 8" too. they are water and air tight. they used to make screen inserts for them but I have not been able to find any lately. you could mount window screen under the floor. highdesertranger

 

[Vagabound]

Have you thought about having a sheet metal shop fabricate he one piece aluminum or stainless steel roof for you? That way it would be seam free other than any thru holes.

Not very sure what you're talking about. My roof in general is fine and it is already aluminum.

Tom

 

[Vagabound]

for a floor vent I would use a deck plate like this,  https://www.amazon.com/Beckson-Twis...346141&sr=8-10&keywords=deck+plate&th=1&psc=1 .  that's a 6 inch they come in 8" too. they are water and air tight.  they used to make screen inserts for them but I have not been able to find any lately.  you could mount window screen under the floor.  highdesertranger

Yeah, I think adding a screen of some kind would be a must. It looks like with that type, the vent is either 100% open or 100% closed. Is that right?

Tom

 

[highdesertranger]

you are correct. but when it's closed it's closed. highdesertranger

 

[bullfrog]

I used a 4" black pipe driveway drain from Home Depot. It is about 6" square and with 2 screws had a removable grate which I put screen under. I put a 4" elbow on it and a pipe cap to completely close it off when traveling. I found in cold weather setting a water bottle in it let in just the right amount of air and as it was under my bed made a drink of ice cold water within reach.

 

[slem]

12286[/ATTACH]  Vagabound pid='278184' dateline='1491339274']Happy to steer back in the direction of the thread topic ...


4. A floor vent is going to make a pretty big hole in the floor, if I use the one I'm thinking about. Any thoughts on keeping creatures out?

Thanks,

Tom

This hatch was my floor vent solution.  Open at will, no bugs, nice. http://beckson.com/ports.html
View attachment 12285 http://beckson.com/ports.html

 

[Vagabound]

I used a 4" black pipe driveway drain from Home Depot.  It is about 6" square and with 2 screws had a removable grate ...

Interesting. If you don't mind, when you get a free minute, could you try to find a picture of it or a link and post it? Thanks.

Tom

 

[Vagabound]

This hatch was my floor vent solution.  Open at will, no bugs, nice. http://beckson.com/ports.html
 http://beckson.com/ports.html

Cool. Unfortunately, their website seems to make a game out of hiding the prices. Do you remember which one you got?

Tom

 

[AbuelaLoca]

Is it necessary to have a floor vent? What is the purpose? Is there some other way to accomplish the same function without cutting a hole in the floor? In all the van build videos I've watched, no one has put in a floor vent...

 

[ArtW]

It isn't necessary, but it does give extra venting

 

[AbuelaLoca]

Could one potentially have a floor vent *instead of a roof vent? Would that be enough to say, run a Mr Buddy heater in the cold or move air around with a 12V fan during the warmer months? I'm dreading the installation of a roof fan/vent, but asking about cutting a 4" or bigger hole in the floor... hmmm

 

[John61CT]

Yes to venting a Buddy, but I'd still tiny-crack a window. CO monitor still needed IMO.

but for cooling you really want throughput, in one low end out the other high.

And just one pair of 4" is too small in hot weather, search for SternWake's screed on his system

 

[highdesertranger]

the problem is when it's hot, the hot air rises so a vent on the roof is the most efficient. but also putting one on the floor will help tremendously with air circulation. however the one on the floor must be air tight on a vehicle, sealing out exhaust fumes while running the engine. this is why I recommend deck plates. highdesertranger