Fantastic Fans in Penthouse Top

LenS · 03-26-2009, 08:39 PM

We got our Penthouse top installed on our extended Chev. van Tuesday/Wednesday. It looks great. Now re-installing all the stuff I had to remove for them to do it. I did have two Fantastic fans mounted in the van steel roof. Sportsmobile does not recommend installing vents in the Penthouse roof. Has anyone installed a roof vent in their penthouse top?? I do think it would be a plus on hot still days even with the ample number of windows in the penthouse. So again, has anyone done it??

surfgeek33 · 03-26-2009, 10:28 PM

Hi Len,

We also wanted to put a fan on our PH. However SMB says they can't. Did they give you the reason why they could not?

Ray

LenS · 03-27-2009, 08:05 AM

The roof ribs will not allow sealing around the vent.

I think the real concern is that the plywood that stiffens the roof is laminated into the roof running fore-aft. If one if the plywood strips is cut for a vent it could be significantly weakened.

The solution to that seems to me to locate the fan as near an end of the roof as possible, indeed maybe in a corner area. I think I have the skills to fill in between roof ribs with fiberglass and epoxy to the make a smooth surface to mount and seal the fan on.

Not high on priority list. Want to try penthouse with its natural ventilation for a while before I commit to putting a hole in it.

Jeffrey · 03-27-2009, 09:31 AM

With 5 large fully opening windows up there, I often have too much ventilation. Even with two open, I have a strong breeze passing thru. Why the need for a much smaller vent?

LenS · 03-27-2009, 05:31 PM

Not sure I need one yet. But the "small vent" Fantastic fan is a very quite variable speed 10 blade low draw fan that really moves air. We also have for many years used a screen house that walls are 100% screening. In still hot weather with some sun the inside was still noticeably hotter then the air outside. Many times in the northern woods you can hear the wind in the trees but at ground level the air can be very still.

At high speed the fan draws about 920cfm which should be about 1.5 air exchanges per minute. So on hot, humid, still nights the fan may be a very positive addition. Also the fan is "free" since I already own two!

Greg In Austin · 03-28-2009, 02:29 PM

We always carry a portable Fantastic Fan as well as a small oscilating fan. We often hang our Fantastic fan on one of the forward PFT J hooks and direct the fan facing in or out as needed.

LenS · 03-29-2009, 06:14 PM

It would appear that although many have mounted equipment ON TO the penthouse roof no one have put a "large" (14" x 14") hole through their roof. Not sure I want to be the first w/o a lot of study.

Thanks for the replies.

mwilliamshs · 02-18-2017, 12:54 PM

researching this myself. fully intend on installing a maxxfan in my 89 Penthouse with ribs. My plan is to add a plywood layer to the roof and glass it in, add fiberglass walls inside the ribs to "dam them up", then cut through and add my vent. It's a bit of work but not rocket science. If strength is still a concern I can sister the gap front-to-rear with something even stiffer than the plywood. I plan to add a subframe to the roof made out of uni-strut and that should lend a good bit of stiffness as well. The subframe is for the attachment of solar panels, plan to use the existing PH penetrations for attaching it, including the rearmost.

Done lots of searching and haven't found any completed installations of roof vent on ribbed PH. Any links?

Scalf77 · 02-18-2017, 01:05 PM

http://www.sportsmobileforum.com/for...50-2725-2.html

mwilliamshs · 02-18-2017, 01:18 PM

Thanks, Scalf! That last post is almost exactly what I had in mind, except that I'll glass up the whole thing for attachment and sealing.