trading vent hatch for a fan

[April Wilcox]

So we have been thinking about adding this 2 way fan I bought a while back to our 13'. We currently have the "escape" fanless vent on the roof, but have considered removing that and installing the fan there, patching up the extra gap that makes up the size difference. The vent that is there now,(which is rectangle) is the same width but a few inches longer than the fan (which is square). Any ideas on what is best to use for covering up the hole? I started thinking this would be way less risky than cutting a new hole in the other part of the roof. Anyone have any ideas or pointers on this before we take it on? We probably won't get this one done for a while, so there is plenty of time to consider my options. I have watched a youtube video of a fan being installed, and think I have a pretty good grasp on the need for butal tape, stainless screws and sealing the finished work to prevent leaks, as this will be over our bed area. Any help or words advice will be appreciated!!

[Jim Bago]

We have two MaxAir units and the original two escape hatch/vents on our Scamp '19 foot. Rather than trying to fill in the original vent. I would locate a good spot for a second vent. It allows for more air flow on humid days. We enjoy the low profile of the MaxAir untis and the fact that you can run them while traveling...even in the rain. We also find the escape hatches as a good source of light on overcast days.

[Raya]

Hi April,

I think that to do a "proper" fill-in of the hole, if you were to go the route of making it smaller, you'd want to use fiberglass cloth and resin to do the job. It's not difficult, but it is a bit fussy and time-consuming.

Here are two options I would consider:

1) Add the new vent somewhere else. It sounds "worse," but I think it would actually be much easier, and as a potential bonus, you'd have more ventilation. Cutting a new hole is quite a bit simpler, less expensive (unless you already have fiberglassing supplies), and less demanding overall.

2) Add a fan that could be used with your existing vent. I've seen a couple of variations on this:

a: I've seen people add a swing-away fan, so that it could be used in front of the vent, away from the vent, or the vent could be fan-free.I've seen this type of fan mounted on, say, the kitchen cabinets where it could swing out to the area in front of the skylight screen. Here is one nice swinging marine 12v fan that I've used (both models). Also, I don't know what your new vent fan draws, but this fan draws far less power than, say, a Fantastic Vent's fan*

These are the Hella Jet and Hella Turbo fans (Jet on left). The turbo has two speeds, but I find that the Jet is a really good fan (speed is like the low speed on Turbo and I tend to use that one anyway), and it completely swivels around on its base (whereas the Turbo only swings on two axes. I wouldn't have been able to survive without a Hella fan near my bunk in the tropics (no AC)





Here is one place that sells them:

http://www.discountmarinesupplies.com/Elec...ERSAL_FANS.html

b: Add something like a computer fan to your existing vent. Here are a couple of photos I saved wherein someone made an aluminum track that a framed computer muffin fan could slide in and out of. (I don't have the photo of it with the fan not in position, but there would just be the rails left.) Perhaps you could adapt the idea:








Just some ideas

*Here is a comparison; I don't remember and don't have time to look up the cfm comparison right now, but what was important to me was the ability to get down to .5 amp or less of draw and still have fannage. I other words, the Fantastic fan probably moves more bulk air.

(Fantastic amp draw = 1.86 amp on Low; 2.29 amp on Medium; 3.0 amp on High)
(Hella Turbo draw = .3 amp on Low; .5 amp on High)

Raya

[Frederick L. Simson]

The vent that is there now,(which is rectangle) is the same width but a few inches longer than the fan (which is square). Any ideas on what is best to use for covering up the hole? I started thinking this would be way less risky than cutting a new hole in the other part of the roof. [b]Anyone have any ideas or pointers on this before we take it on?

If I remember correctly, that "escape hatch/roof vent" is 14" x 22".
Instead of closing up part of that hole, how about enlarging it by 3" on each side and mounting [b]2 Fan-tastic vents side-by-side?

[floyd]

So we have been thinking about adding this 2 way fan I bought a while back to our 13'. We currently have the "escape" fanless vent on the roof, but have considered removing that and installing the fan there, patching up the extra gap that makes up the size difference. The vent that is there now,(which is rectangle) is the same width but a few inches longer than the fan (which is square). Any ideas on what is best to use for covering up the hole? I started thinking this would be way less risky than cutting a new hole in the other part of the roof. Anyone have any ideas or pointers on this before we take it on? We probably won't get this one done for a while, so there is plenty of time to consider my options. I have watched a youtube video of a fan being installed, and think I have a pretty good grasp on the need for butal tape, stainless screws and sealing the finished work to prevent leaks, as this will be over our bed area. Any help or words advice will be appreciated!!

Your new vent comes with a template for cutting the hole,It is not a challenge if you would rather have it somewhere else in the camper.
If you want to convert your escape hatch /vent, you could buy a piece of material to make up the space on the sides [maybe ABS or Fiberglass sheeting] for the roof side.

On the inside I would suggest putting a light on each side to cover the space and add utility, you will be running 12V up there anyway. An oak frame would finish it off nicely.
Or I usually use the plastic wood grain vertical deck spindles ,they are about 1-1/4" X1-1/4" and don't warp or rot and it holds screws very securely.

[April Wilcox]

I guess it would help to mention that I already bought a new escape hatch to replace the old one, and also a 2 way variable speed 14"x14" roof vent fan. So I already have these two items on hand, brand new and ready to install. Kirk mentioned he liked the idea of having the fan over the bed, which is where the current vent is, so I was considering scratching the new escape vent installation and just installing the fan there instead. It is starting to look like I should stick to the original idea of replacing the old vent hatch with the new one, and cutting the hole at the other end of the trailer for the fan. I think we can handle the cutting of the hole, and installing the fan, I was more concerned about messing with the structural integrity of the roof, by cutting a big hole in it. Should this be a concern?

[Raya]

I wouldn't think it would be a problem unless you put the new one very close to the current one.

You could beef up a bit around the hole with a bit of framing (say, 1 x 2 stock epoxied in place), but I don't think it's necessary. The roofs on our eggs aren't strong enough to support weight in any case (so you're not "losing" that ability since you don't have it now). Also, the fan vent is probably very lightweight.

I agree with your re-thought plan. If it were me I would consider getting one of the Hella Jet fans I mentioned above, and mount it somewhere (not necessarily adjacent to the roof vent) where you can aim it to blow on your bed at night. The air from one of those is quite cooling, and you're drawing only a fraction of an amp.

Raya

[Raya]

I just thought of one thing I'd like to add. It's probably nothing you'd ever need or want, but... just in case.

If you ever did want to slightly support the roof - or to put up a privacy curtain for the bed (or both), one way to do it is to run a small "header" across the roof that lines up with the back face of the closet and the back face of the kitchen cabinets. Not that it would be a massive amount of support, but it's the sort of thing where if you did get a wee sag or deformation, it would contribute to a fix. Plus the curtain thing.

So, if you keep the new skylight forward of that line, you'll have that option.

Raya

[Joy A]

April,

When you order a Scamp with a vent fan they simply put it forward of the large exit vent. Replace the exit vent and cut a hole for the new fan forward of it. It's still dark here but as soon as I can I'll go measure mine and take a picture.

I actually like having the two vents. Lots of air comes in when needed.

[April Wilcox]

Seeing that I already have the replacement vent AND fan, we should probably go ahead and install them both. One of the reasons I post ideas here first is to get a feel for things I might be overlooking, or somebody might already have tried it, and can give me educated advice. I can see the advantages of having 2 vents. I guess we should trust that we can pull this off without making any major blunders in the process. So far we only have experience making drill holes in the fiberglass. Cutting a larger hole in the roof is a bit unnerving, but I can see that it looks like something we can accomplish. I appreciate all the advice, and will post updates (and photos) as to what we end up actually doing. Thanks again everybody!

[Joy A]

April,

To help you out in the placement of your fan. The factory placed miine 16 inches forward of the exit vent. This puts it just about overhead standing at the stove.

[April Wilcox]

Thanks Joy, that looks like the same placement we had in mind as well.

[Carol H]

Seeing that I already have the replacement vent AND fan, we should probably go ahead and install them both. One of the reasons I post ideas here first is to get a feel for things I might be overlooking, or somebody might already have tried it, and can give me educated advice. I can see the advantages of having 2 vents. I guess we should trust that we can pull this off without making any major blunders in the process. So far we only have experience making drill holes in the fiberglass. Cutting a larger hole in the roof is a bit unnerving, but I can see that it looks like something we can accomplish. I appreciate all the advice, and will post updates (and photos) as to what we end up actually doing. Thanks again everybody!

I understand the fear. Had a new vent sitting in a box for 8 months before I got the courage up to cut the hole for it! LOL Turned out easier than I thought it would be and sorry I wanted so long to get my nerve up. To make yourself feel safer about it just cut the first hole a little bit tight and then sand it down to fit. Easier than it sounds. Go for it you will not be sorry.

Carol